Alfatron ALF-DSP44-U 4×4 Digital Sound Processor User Manual
- June 10, 2024
- ALFATRON
Table of Contents
ALF-DSP44-U 4×4 Digital Sound Processor
ALF-DSP User Guide
The ALF-DSP is a digital sound processor available in four
different configurations:
- ALF-DSP44-U – 4×4 Digital Sound Processor
- ALF-DSP44-UD – 4×4 Digital Sound Processor with Dante
- ALF-DSP88-U – 8×8 Digital Sound Processor
- ALF-DSP88-UD – 8×8 Digital Sound Processor with Dante
Hardware
The ALF-DSP offers balanced and unbalanced audio connections for
both input and output terminals. The system uses an ADI SHARC 21489
processor and supports a sampling rate of 48KHz and digitizing bit
of 24-bit. The following are the specifications:
- I/O:
- ALF-DSP44-U – 4-in / 4-out
- ALF-DSP44-UD – 1-in / 1-out
- ALF-DSP88-U – 4-in / 4-out
- ALF-DSP88-UD – 1-in / 1-out
- Processor: ADI SHARC 21489(x1)
- Sampling Rate/Digitizing Bit: 48KHz/24bit
- System Latency: Input & Output Specifications
- Input Gain: Power Requirements
- Maximum Power Consumption
- Rack Space: Dimensions (W x D x H)
- Shipping Weight
Technology Overview
The ALF-DSP features digital signal processing technology that
allows for advanced audio processing and control. The system
supports external control programmer and control protocols such as
Serial Port-to-UDP (RS232 To UDP). The software and control
features are discussed in detail in the following sections.
Software
The ALF-DSP features advanced software that allows for
customized audio processing and control. The software includes the
following:
- Processing
- Routing
- Mixing
- Equalization
- Dynamics Processing
- Delay
- Filters
Control
The ALF-DSP supports external control programmer and control
protocols such as Serial Port-to-UDP (RS232 To UDP). The following
are the control features:
External Control Programmer
The ALF-DSP supports external control programmer that allows for
customized audio processing and control. Users can create custom
presets that can be used to quickly adjust settings for different
audio sources.
Control Protocol
The ALF-DSP supports a variety of control protocols including
Serial Port-to-UDP (RS232 To UDP) that allows for easy integration
with other audio systems and devices.
Serial Port-to-UDP (RS232 To UDP)
The Serial Port-to-UDP (RS232 To UDP) protocol allows for
seamless integration with other networked audio devices. The
protocol supports both RS232 and UDP connections and allows for
easy remote control and automation of the ALF-DSP system.
Product Usage Instructions: 1. Connect the ALF-DSP to your audio
system using either balanced or unbalanced audio connections. 2.
Use the advanced software to customize the audio processing,
routing, mixing, equalization, dynamics processing, delay, and
filters. 3. Use the external control programmer and control
protocols such as Serial Port-to-UDP (RS232 To UDP) to control and
automate the ALF-DSP system. 4. Refer to the user manual for
detailed instructions on how to use the ALF-DSP system.
ALF-DSP USER GUIDE
ALF-DSP44-U
4×4 Digital Sound Processor
ALF-DSP44-UD
4×4 Digital Sound Processor with Dante
ALF-DSP88-U
8×8 Digital Sound Processor
ALF-DSP88-UD
8×8 Digital Sound Processor with Dante
All Rights Reserved
Version: ALF-DSPxxxxx – V2.0 19072022
ALF-DSP88-U
Table of Contents
1. Hardware………………………………………………………………………………….5
1.1 Safety Instructions ……………………………………………………………………………………………………………………5 1.2
Audio Wiring Reference…………………………………………………………………………………………………………….6 1.3
Specifications…………………………………………………………………………………………………………………………..7 1.4
Mechanical………………………………………………………………………………………………………………………………8 1.5 Front Panel
……………………………………………………………………………………………………………………………..8 1.6 Rear
Panel………………………………………………………………………………………………………………………………8
2. Technology Overview ………………………………………………………………..9
2.1 Introduction to DSP Technology…………………………………………………………………………………………………9 2.2
Audio Input Section ………………………………………………………………………………………………………………….9 2.3 Audio
Output Section…………………………………………………………………………………………………………….100 2.4 Floating Point
DSP ……………………………………………………………………………………………………………….111 2.5 Audio Flow
…………………………………………………………………………………………………………………………..122 2.6 Typical System
Application ……………………………………………………………………………………………………133
3. Software ……………………………………………………………………………….133
3.1 Software Installation ……………………………………………………………………………………………………………..133 3.2
Using the Software …………………………………………………………………………………………………………………14 3.3 Module
Editing ……………………………………………………………………………………………………………………….14 3.4 Audio Module
Parameters……………………………………………………………………………………………………….15
3.4.1 Input Source ………………………………………………………………………………………………………………….155 3.4.2
Expander ………………………………………………………………………………………………………………………166 3.4.3 Compressor &
Limiter……………………………………………………………………………………………………….17 3.4.4 Automatic Gain Control
…………………………………………………………………………………………………….18 3.4.5 Equalizers
……………………………………………………………………………………………………………………….19 3.4.6 Graphic
Equalizer…………………………………………………………………………………………..20 3.4.7 Feedback Suppressor
………………………………………………………………………………………………………21 3.4.8 Noise
Gate…………………………………………………………………………………………………………………..2422 3.4.9 Ducker
………………………………………………………………………………………………………………………….243 3.4.10 Ambient Noise
Compensation (ANC)………………………………………………………………………………243 3.4.11
AutoMixer………………………………………………………………………………………………………………………24 3.4.12 Acoustic Echo
Cancelation………………………………………………………………………………………………26
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3.4.13 Noise Suppression …………………………………………………………………………………………………………27 3.4.14
Matrix ……………………………………………………………………………………………………………………………27 3.4.15 High & Low
Pass Filter ……………………………………………………………………………………………………27 3.4.16
Delay…………………………………………………………………………………………………………………………….28 3.4.17 Output
…………………………………………………………………………………………………………………………..29 3.4.18 USB Interface
………………………………………………………………………………………………………………..29 3.4.19 Camera
Tracking……………………………………………………………………………………………………………31 3.5 Setting Menu
…………………………………………………………………………………………………………………………32 3.5.1 File Menu
………………………………………………………………………………………………………………………..32 3.5.2 Device
Setting………………………………………………………………………………………………………………….32 3.5.3 GPIO
Setting……………………………………………………………………………………………………………………33 3.5.4 Group
Setting…………………………………………………………………………………………………………………..35 3.5.5 Panel Setting
…………………………………………………………………………………………………………………..36 3.5.6 Dante Settings
……………………………………………………………………………………………………………….. 38 3.5.7 Help Menu
………………………………………………………………………………………………………………………41
4. Control……………………………………………………………………………………42
4.1 External Control Programmer…………………………………………………………………………………………………..42 4.2
Control Protocol……………………………………………………………………………………………………………………..42 4.3 Serial
Port-to-UDP (RS232 To UDP) ………………………………………………………………………………………..43
5. FAQs ……………………………………………………………………………………..46 Appendix A: Module ID
Distribution ………………………………………………47 Appendix B: Module Parameter Types
(1)……………………………………..48 7. After-Sales………………………………………………………………………………50 8.
Warranty …………………………………………………………………………………51
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Preface
Read this user manual carefully before using the product. Pictures shown in
this manual are for reference only. Different models and specifications are
subject to the real product. This manual is only for operational instruction,
please contact the local distributor for maintenance assistance. The functions
described in this version are updated as of September 2021. In the constant
effort to improve the product, we reserve the right to make functions or
parameters changes without notice or obligation. Please refer to the dealers
for the latest details.
FCC Statement
This equipment generates, uses, and can radiate radio frequency energy and, if
not installed and used in accordance with the instructions, may cause harmful
interference to radio communications. It has been tested and found to comply
with the limits for a Class B digital device, pursuant to part 15 of the FCC
Rules. These limits are designed to provide reasonable protection against
harmful interference in a commercial installation. Operation of this equipment
in a residential area is likely to cause interference, in which case the user
at their own expense will be required to take whatever measures may be
necessary to correct the interference. Any changes or modifications not
expressly approved by the manufacturer would void the user’s authority to
operate the equipment.
Do not dispose of this product with the normal household waste at the end of
its life cycle. Return it to a collection point for the recycling of
electrical and electronic devices. This is indicated by the symbol on the
product, user manual or packaging. The materials are reusable according to
their markings. By reusing, recycling or other forms of utilisation of old
devices you make an important contribution to the protection of our
environment. Please contact your local authorities for details about
collection points.
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1. Hardware
1.1 Safety Instructions
Safety Instructions Important safety instructions: 1. Read these instructions.
2. Keep these instructions secure. 3. Pay attention to all warnings. 4. Follow
all instructions. 5. Please keep the device away from water. The device cannot
be exposed to water drips or water splashes; make sure that there is no object
with liquid near the device, such as a vase. 6. Please use dry cloth to clean
the device. 7. Please do not block the vent. Please install the device based
on the manufacturer’s instructions. 8. Please do not install near any heat
source, such as radiator, furnace, or other devices (including amplifiers)
that generate heat. 9. Please make use of a protective grounding connection to
connect the device to the power socket. Please do not use polarized plug or
grounding plug. A polarized plug has two leaves, and one is wider than
another. A grounding plug has two leaves and a third ground terminal. The wide
leaf or third ground terminal can provide safety for the users. If the plug
provided does not correspond with the power socket, please contact an
electrician to replace the old socket with a new one. 10. Protect the power
cord so that it will not be trampled or jutted, particularly the plug, the
socket and the connections of cord and device. 11. Please use the accessories
designated by the manufacturer. 12. Please only use a cart, a tripod, or a
desk designated by the manufacturer, or sold together with the device. When
using a cart, please take care with the mobile cart / device to avoid injury
from rollover. 13. Please unplug the device during a thunderstorm or during
the idle period. 14. Please contact our qualified maintenance personnel to
deal with all maintenance related issues. For example, the power cord gets
damaged, liquid has spilt over, or an object falls onto the device; the device
is exposed to rainwater or moisture; the operations are not correct, or the
device completely fails.
The lightning logo (an equilateral triangle with an arrow) is used to make the
users aware of the uninsulated “dangerous voltage” within the product shell,
which may cause electric shock. An equilateral triangle with an exclamation
mark is adopted to make the users understand the importance of the operations
and maintenance instructions given in the appendixes attached to the product.
Warning: In order to prevent electric shock, please do not use a polarized
plug provided by a device with an extension cord. The socket outlet cannot be
inserted except for the sharp end.
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1.2 Audio Wiring Reference
Balanced Audio Connection Any of these audio connections may occur on either
input or output terminals.
Unbalanced Audio Connection RCA audio connections and 1/4-inch TS audio
connections are unbalanced connections. A multi-strand shielded conductor may
be installed on both ends of the unbalanced connection. In such a case, please
note to join the negative and shield conductors as indicated.
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1.3 Specifications
I/O ANALOGUE DIGITAL USB PROCESSING
PROCESSOR
SAMPLING RATE/ DIGITIZING BIT SYSTEM LATENCY INPUT & OUTPUT SPECIFICATIONS
INPUT GAIN
PHANTOM POWER FREQUENCY RESPONSE (20-20KHz) MAXIMUM LEVEL THD + NOISE DYNAMIC
RANGE BACKGROUND NOISE (A-WEIGHTED) CHANNEL ISOLATION @1KHz INPUT IMPEDANCE
OUTPUT IMPEDANCE AUDIO PROCESSING MODULES ACOUSTIC ECHO CANCELLATION (AEC)
AMBIENT NOISE COMPENSATION (ANC) AUTO MIXER AUTOMATIC GAIN CONTROL (AGC)
AUTOMATIC NOISE SUPPRESSION (ANS) COMPRESSOR DELAY DUCKER EXPANDER FEEDBACK
SUPPRESSOR GRAPHIC EQUALIZER HIGH/ LOW PASS FILTER LIMITER MATRIX NOISE GATE
PARAMETRIC EQUALIZER CAMERA CONTROL CONTROL & INTERFACE OPTIONS ETHERNET
SERIAL PORT GPIO MECHANICAL
POWER REQUIREMENTS
MAXIMUM POWER CONSUMPTION RACK SPACE DIMENTIONS (W x D x H) SHIPPING WEIGHT
ALF-DSP44-U
4-in / 4-out –
1-in / 1-out
ADI SHARC 21489(x1) 48KHz / 24bit
<3ms
0 48dB in 6dB Steps
Y (2-channels)
Y Y
Y Y Y Y Y Y Y Y Y –
1 LAN 1 RS-232 / 1 RS-485
–
110-240V AC 50Hz60Hz
<40W Half Rack 215 x 184 x 45mm
1,8KG
ALF-DSP44-UD
4-in / 4-out 4-in / 4-out 1-in / 1-out
ADI SHARC 21489(x2) 48KHz / 24bit
<3ms
ALF-DSP88-U
8-in / 8-out –
1-in / 1-out
ADI SHARC 21489(x2) 48KHz / 24bit
<3ms
ALF-DSP88-UD
8-in / 8-out 8-in / 8-out 1-in / 1-out
ADI SHARC 21489(x2) 48KHz / 24bit
<3ms
0 48dB in 3dB Steps
48V ±0.2dB +24dBu 0.003%@4dBu 110 dB -91 dBA 108 dB 9.4K 102
Y (2-channels)
Y Y
Y Y Y Y Y Y Y Y Y –
Y (1-channel)
Y Y Y
Y Y Y Y Y Y Y Y Y Y Y Y Y
Y (1-channel)
Y Y Y
Y Y Y Y Y Y Y Y Y Y Y Y Y
1 LAN / 1 DANTE 1 RS-232 / 1 RS-485
8GPI / 8GPO
1 LAN 1 RS-232 / 1 RS-485
8GPI / 8GPO
1 LAN / 2 DANTE 1 RS-232 / 1 RS-485
8GPI / 8GPO
110-240V AC 50Hz60Hz
<40W Half Rack 215 x 184 x 45mm
1,8KG
110-240V AC 50Hz60Hz
<40W 1U
482 x 260 x 45mm 3KG
110-240V AC 50Hz60Hz
<40W 1U
482 x 260 x 45mm 3KG
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ALF-DSP88-U
1.4 Mechanical
Ventilation: The recommended highest operating ambient temperature is 30 / 86.
Make sure that there is no obstruction on both sides (a gap of at least 5.08cm
/ 2 inches shall be reserved). Please do not cover the thermal vents of the
device with newspapers, a tablecloth, or any other objects.
1.5 Front Panel
ALF-DSP44-U / ALF-DSP44-UD
ALF-DSP88-U / ALF-DSP88-UD Power: LED power indicator. STATUS: The operational
status indicator of the device. USB AUDIO: USB audio for connection to host
PC. (1-in / 1-out) I/O: Shows signal status of Input / Outputs.
1.6 Rear Panel
ALF-DSP44-U/ ALF-DSP44-UD
ALF-DSP88-U/ ALF-DSP88-UD
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ALF-DSP88-U
Power switch: Turn unit on / off. (ALF-DSP88-U and ALF-DSP88UD ONLY) Power
connector: (Supports 110 – 240V AC 50/60Hz, and supports a maximum power of
40W) Ethernet Connector: 10/100 Base-T Ethernet connector is used for IP-based
PC software and host control, and
third-party accessory controller. Dante Connections: Dante connections for
connecting to Dante Digital Media Network.
(ALF-DSP44-UD and ALF-DSP88-UD ONLY) RS-485: Used for the serial communication
port Tx = sending or data output or Rx = receiving or data input
that connects to a third-party control device. Port setting: 115200 baud
(default), 8 data bits, 1 stop bit, no parity, no flow control. RS-232: Used
for serial communication; port Tx = sending or data output or Rx = receiving
or data input that connects to a third-party control device. Port settings:
115200 baud (default), 8 data bits, 1 stop bit, no parity, no flow control.
RS485 & RS-232 can be used for voice tracking control (or other output
commands), or for bus input control. A central command can be used to
conveniently integrate into your software. GPIO: 8-channel logic connections,
with 4 pairs of universal grounding pins. After being activated, the logic
output will be low (0V), and the internal voltage will be high (5V) when not
activated. You may directly power and light up external LEDs. The logic output
can be driven by the logic output control module in the device design.
Polarity and threshold can be set in the software. INPUTS: Balanced mic/line
level audio inputs with +48V Phantom power. OUTPUTS: Balanced line level audio
outputs.
2. Technology Overview
2.1 Introduction to DSP Technology
Audio Digital Signal Processors (DSP) are equipped with several core technical
features to simulate the work of an audio engineer. DSP-based audio
management, routing, processing, and control is facilitated via a computer
running the GUI Software for the Audio DSP Hardware. This Manual mainly
introduces the te chniques used to achieve this goal.
The DSP Controller software is a Windows-based application, which is used to
configure and control the DSP hardware. The DSP Controller has 16 built-in
presets, and the modules and sequences for each preset can be flexibly
designed in accordance with the designer’s requirements. Once the design is
completed, it can be saved for future use. The sequences and parameters of the
DSP Controller’s built-in processing modules work with most application
scenarios without needing any changes.
The DSP Controller is a full-feature application, including parameter
adjustments and peripheral accessory settings of all modules, such as RS232,
RS485, and click-and-drag panel configuration etc. The most interesting part
is the user interface, which allows the engineer to customize the user
interface so that the integrator can edit it, or the onsite technicians or end
users who have no idea of the relevant techniques can operate it. Advanced
security features make it possible for the end user to only access the
controls allowed by the engineer, or designer.
2.2 Audio Input Section
The DSP’s supports up to 4 or 8 fixed analogue audio inputs (model dependent),
which can be connected via removable balanced phoenix connectors. The analogue
input section supports microphone or line-level signals whose nominal levels
range from 0dBu to +48dBu in 3dBu steps.
+48VDC phantom power can be independently switched on/ off for each input.
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Preamp gain and phantom power can be conveniently controlled via the DSP
Controller. The Analogue to Digital (A/D) converter, or ADC, adopts an
advanced 24-bit 256X sampling rate converter.
Analogue to Digital (A/D) Converter Technical Specs: Sampling rate: 48kHz THD+N: 105dB Dynamic range: 120dB Audio format: 24Bit MSB TDM
2.3 Audio Output Section
The Analogue
output section
refers to the
digital to
analogue (D/A)
converter, or DAC,
also adopts an advanced 24-bit 256X sampling converter. Just like the A/D converter, it also uses multi-bit
architecture for broader dynamic range. Unit gain (0dB) is set via volume control, and the analogue output
section
is
corrected as +4dBu with 20dB headroom. That is to say that 0dBFS digital
signal is equivalent to +24dBu output signal. If other signal levels are
required, you may change the output volume to achieve it.
Digital to Analogue (D/A) Technical Specs: Sampling rate: 48kHz THD+N: -100dB
Dynamic range (A-weighted): 118dB Audio format: 24Bit MSB TDM
On the software output interface there are two controls: Phase and Mute.
Phase: The phase button inverts the phase of the output signal by swopping the
polarity. Mute: Mutes the analogue output of the respective channel
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2.4 Floating Point DSP
The ALF-DSP88-U adopts analogue devices’ ADI SHARC audio processors, enabling
32-bit and 40-bit floatingpoint processing, which can be compared to 40-bit
floating-point processing of other devices. Floating-point processing provides
prominent advantages for the users in terms of sound quality and usability.
Fixed-Point Processing Limitations Fixed-point processing has its own
disadvantages. If there is a significant change in gain, data loss or a more
severe error may occur, including clipping or distortion. For example, the
processing of 24-bit fixed point-based audio signal, in some cases, if you
attenuate the signal to 42dB, the new signal only includes 17-bit information.
Due to gain attenuation, 7 bits of information will be lost forever. Worse
than that is the clipping distortion. For a signal nearly close to 0dBFS, the
signal will be clipped at 0dBFS, and audio distortion will occur. Even if the
signal level is adjusted to below 0dBFS through post-regulation, the clipping
has occurred, and the distortion still exists. Fixed point processing can
create some headroom above 0dBFS, but by doing so, some bits have to be
abandoned. For example, if a 12dB (2 bits) headroom is created, a 24-bit
system will only have 22 bits. Floating-Point Processing On the contrary, by
taking advantage of floating-point processing, no matter what the signal level
is, all available bits are uniformly distributed to the signals. Basically,
the floating points use some bits as indexes to set up general signal level
and distribute the remaining bits to signals with independently stored level.
As a result, no matter what kind of level (from -200dB and 200dB below to
0dBFS above, the stored signal’s accuracy is optimized without clipping
distortion. SHARC provides 32-bit and 40-bit accurate processing; through
32-bit processing, 25 bits are distributed to storage signals no matter what
its signal level is. This means that, based on at least 1-bit low level
signal, its accuracy is always significantly superior to 24-bit fixed point
processing. Through expanded 40-bit accurate processing, 33-bit storage
signals can be achieved.
Practical Significance What’s the practical significance of floating-point
processing for the users? The gain stages between multiple modules can be
ignored. If the signal level of a module is reduced by 50dB and is then
restored to its original value through another processing, data loss will not
occur. In the fixed-point system, the users must check other signal levels
before sending it to the A/D converter because all digital-to-analogue
converters adopt fixed points. In the DSP system, if you notice that your
signal has been clipped before it is outputted and transmitted to the digital-
to-analogue converter, you may close it off immediately at the output section
to correct the situation. If using the fixed-point system, you would have to
search each processing module to find the clipping source.
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ALF-DSP88-U
2.5 Audio Flow
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ALF-DSP88-U
2.6 Typical System Application
Conferencing System: The processor can be connected to microphones,
amplifiers, speakers, and other audio peripherals (like USB audio from a PC)
so as to process all audio signals and advanced algorithms like AEC in a
typical conferencing system. Additional audio matrixing, auto mixing and
signal routing is also achieved in this application to facilitate excellent
audio quality in a conference.
3. Software
3.1 Software Installation
A Windows PC with: · Intel i5 processor or higher · 8 GB or higher memory · 1
GB free storage space · Windows 7 or higher version · Minimum 1920 x 1080
resolution · 24 bit or higher color · Network (Ethernet) port
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ALF-DSP88-U
Software Installation: Visit the device web page address: 169.254.10.227
1. Download software from the product website and install files. 2. Double
click the downloaded file and install by following the instructions on the
screen. After the software is installed, read other parts of the help file, or
execute the software. After the software is installed, use one of the
following methods to open the software: 1. Double Click Desktop Icon 2. Open
from Start menu
3.2 Using the Software
After enabling the software, the main menu is shown as below:
Click the button
in the right corner of the main menu to find all processors on the network
automatically. The user may connect to the designated processor based on their own needs; after the connection,
the indicator will flash; each processor supports simultaneous connection and control for up to four users.
3.3 Custom edit processing module
Click on the edit button, input or output channel processor module right-click
selection, edit dialog box, can replace the current processing module, can
delete, copy and other operations, edit good click upload to the host. Note:
when the CPU display more than 100 will turn red, this time the resource can
not be uploaded to the host, need to be re-edited.
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ALF-DSP88-U
3.4 Audio Module Parameters
There are two ways to access the audio module parameters: first, click the
input or output channel module you wish to access, and enter the parameter
interface of the module; secondly, right click the channel module and the
configuration interface will pop out. This is used for the following module
parameters.
3.4.1 Input Source
Sensitivity: Microphone gain, 0dB – 48dB in 3dB Steps. Phantom Power: Provides
+48V phantom power for external condenser microphones. (Do not enable phantom
power when the power is not required, this is to prevent damaging any non-
Phantom powered devices when connected.)
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ALF-DSP88-U
Sine Wave: Select the Sine Wave button and drag the frequency to generate sine
wave with selected frequency (selectable 20Hz – 20 kHz). You may regulate the
output level (unit: dBFS) based on your requirements. Use the level fader to
adjust or click the text field to designate a value. White Noise: When
observed on the frequency spectrograph with constant bandwidth, and set to a
flat frequency spectrum, white noise signal has equal energy across all
frequencies. Pink Noise: The frequency intensity level of pink noise is mainly
distributed in the middle and low frequency bands. It decreases with a speed
of 3dB/Oct in the middle and low frequency bands. In addition, you may also
find the following menu by right clicking each fader on the main menu.
Group Setting: Open the group setting interface window. Minimum and Maximum
Gains: Limit the maximum and minimum values of a channel. After it is
commissioned, if you do not wish that the system’s stability is affected due
to external factors, you may set up a maximum gain.
3.4.2 Expander
Although similar in concept, the expander has a different operating principle
from the compressor. It can expand the dynamic range of a signal. The most
fundamental difference in these two devices lies in that, the compressor works
on the signal higher than the threshold, while the expander works on the
signal lower than the threshold. Louder and softer signals become relatively
louder and softer respectively. It can be seen from Fig.3.2 that, when the
expansion ratio reaches 1:2, the input signal 20dB lower than the threshold
will generate an output signal 40dB lower than the threshold. Thus, as shown
below, the signal lower than the threshold will extend downwards and cause
softer level. When an expansion ratio 1:20 is adopted. The expander seems to
be a noise gate in terms of the transmission features. In fact, a noise gate
is an expander with a great expansion ratio.
Fig.3.2 Expander The expander has the following control parameters: Threshold:
The expander activates only when the signal exceeds this threshold (allowing
the transmission of the signal). As a standard practice, the signal is often
set at the ambient noise level Ratio: Ratio refers to the slope below the
threshold point on the gain curve. When the slope is set at a high level,
gating will activate.
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Attack: Attack refers to the time that the expander will wait before
activating when the input signal exceeds the threshold. Shorter attack time
allows to start the expander more quickly. Release time: Release time refers
to the delay in time required for the gain to be restored to normal when the
input signal drops lower than the threshold. No matter the starting time or
the release time, it just helps to reduce the speed of gain attenuation. That
is to say, the speed of the gain from -40dB to 0dB is slowed down due to the
influence of Attack. The Attack time and Release time is unrelated to the
threshold. If the signal level falls below the threshold, the Attack time and
Release time will have their own respective influence on gain attenuation;
when the signal level rises above the threshold, the gain attenuation produced
by the expander will disappear in accordance with the speed controlled by the
Release time. When the gain attenuation is reduced to 0dB, the expander will
stop expansion. Later, when the signal reduces to below the threshold, the
expander will start again, and the release time will begin to work.
3.4.3 Compressor & Limiter
Compressor
The compressor is used to reduce the dynamic range of the signal higher than
the threshold set by the user, and to maintain the dynamic range of the signal
lower than the threshold. The compressor has the following control parameters:
Threshold: When the signal level is higher than the threshold, the compressor
/ limiter begins to reduce the gain. Any signal that exceeds the threshold is
regarded as overshoot signal, and its level will be reduced based on the ratio
set. The more the signal level exceeds the threshold, the more level is
attenuated. Ratio: It refers to the compression ratio. The ratio sets the
attenuation degree of the overshoot signal to the threshold level. The smaller
the compression ratio is, the less compression will take place and signal will
remain higher than the threshold. Once the signal exceeds the threshold, the
compression ratio decides the ratio of input signal variation to output signal
variation. For example, when the compression ratio is 1:2, if the input signal
is 2dB higher than the threshold, the exceeding part only changes by 1dB. A
compression ratio of 1:1 suggests that the compressor does not attenuate the
signal in proportion. The adjustable range of compression ratio is 1-20.
Attack Time & Release Time: In order to maintain natural oscillation, it is
generally accepted that part of the original level will pass through the
compression without any influence, or just minor influence. Likewise, if there
is rapid sharp attenuation and rapid recovery in the signal gain, the suction
effect will occur. The attack and release time of the compressor is to avoid
this effect. The attack time sets the speed of gain attenuation, while the
release time sets the speed of gain recovery.
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Output Gain: Also called gain compensation. If the compressor significantly
reduces the level of the signal, it may need to enhance the output gain to
maintain the volume. Output gain applies to all parts of the signal and is
unrelated to other parameter settings of the compressor. Gain Reduction (G.R.)
and output Level Meter: G.R. indicates the compressor’s compression amount;
output refers to the output level of the signal that has passed through the
compressor module (post compression). The compression amount is displayed in
an inverse level meter. If the input signal and threshold are set as -6dB and
30dB, respectively, and the ratio is 2:1, then the compression amount is 12dB;
the G.R. level meter indicates around -12dB and output indicates around -18dB.
Limiter
The limiter only has one key task: make sure that the signal will not exceed
the threshold level in any way. By adjusting the compressor’s control
parameters, its working modes will be very similar to those of the limiter.
The core working principle of a limiter is that it focuses on the signal below
the threshold level as well as how the gain attenuation is produced before the
occurrence of overshoot signal. The limit period consists of two processing
stages: during the first stage, there is a minor limit, but the overshoot
signal will not be processed; during the second stage, if there is overshoot
signal, it will attenuate with a very high ratio. The limiter only provides
two parameters: Threshold and Release Time. In terms of signal processing,
occasional clipping will be solved with a limiter, while the signal level will
be attenuated in terms of frequent clipping.
3.4.4 Automatic Gain Control
Automatic gain control (AGC) is a type of compressor. Its threshold is set at
a very low level with middle-to-slow attack time, long release time, and low
ratio. The purpose is to improve the signal with an uncertain level to a
target level, while maintaining the dynamic range at the same time. Most of
the auto gain control includes silent detection to prevent the gain
attenuation loss during the silent period. This is the only function that
distinguishes auto gain control from an ordinary compressor / limiter. Auto
gain control may be adopted to normalize the level of CD players that play
background music, foreground music and music on hold, as to eliminate the
changes in the level of some paging microphones.
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Auto gain control includes the following control parameters and switches:
Threshold: When the signal level is lower than the threshold, the input-to-
output ratio is 1:1. When the signal level is higher than the threshold, the
input-to-output ratio changes with the ratio control settings. The threshold
is set as the background noise just higher than the level of input signal.
Ratio: It refers to the ratio of the changes in the level of the input signal
higher than the threshold to the changes in the level of the output signal.
Target Threshold: It refers to the level of output signal required. If the
signal is higher than the threshold, the controller will compress the signal
in proportion. Attack Time: It refers to the response time required to control
the level higher than the threshold. Release Time: It refers to the response
time required to control the level lower than the threshold.
3.4.5 Equalizers
The equalizer is mainly used to correct the frequency range that is
overemphasized or gets lost, no matter if it is wide or narrow. In addition,
the equalizer can also help us to narrow or widen the frequency range or
change the amount of a component in the frequency spectrum. To simplify, the
equalizer can be used to change the tone of the signal.
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The equalizer has the following control parameters: Type: Parametric EQ is the
default setting. High and low shelf filters and high and low pass filters can
also be selected. Each kind of filter has different forms to achieve different
functions. High and Low Pass Filter: The reference frequency of a pass-type
filter is called the cut-off frequency. Pass-type filters allow the
frequencies on one side of the cut-off frequency to fully pass the filter; in
the meantime, the frequencies on the other side of the cut-off frequency are
attenuated at a constant dB ratio per frequency octave. High pass filters
allow the frequencies above the cut-off frequency to pass and filter the
frequencies below the cutoff frequency. To the contrary, low pass filters
allow the frequencies below the cut-off frequency to pass and filter the
frequencies above the cut-off frequency. High and Low Shelf Filter: High shelf
filter means that the gain increases or attenuates for the frequencies above
the set frequency. Low shelf filter means that the gain increases or
attenuates for the frequencies below the set frequency. The set frequency is
not 3dB cut-off frequency but refers to the center of the failing edge or
rising edge of the filter. Q value affects the peak and has a mathematical
relation with the peak. Frequency (Hz): Refers to the center frequency of the
filter. Gain (dB): Refers to the increased or attenuated decibel value of the
gain at the center frequency. Q: It refers to the quality factor of a filter.
The adjustable range of the Q value is 0.02-50. When the filter is set as a
parametric EQ filter, Q value refers to the width of the bell-shaped frequency
response curve on both sides of the cut-off frequency. When the filter is a
high and low shelf filter or a high and low pass filter, if Q>0.707, there
will be peaks in the filter responses. If Q<0.707, the slope will become
flatter, and the roll-off will occur in advance. Each segment of the equalizer
has a switch, which is used to turn on or turn off the corresponding segment.
When turned off, that frequency parameter settings are disabled. The equalizer
has a master switch, which is used to enable or disable the whole module.
3.4.6 Graphic Equalizer
By using a constant Q-value, each frequency point is equipped with a push-pull
potentiometer. The bandwidth of the filter remains unchanged regardless of if
the frequency is raised or attenuated. The common professional graphic
equalizer is to divide 20 Hz~20 kHz signals into 10, 15, 27 or 31 bands /
frequencies to adjust. The graphical equalizer has 10, 15 and 31 band options
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3.4.7 Feedback Suppressor
While using the feedback suppressor module, it is advised to remember that
feedback suppression is not a replacement for a good audio system design and
commissioning. Traditional audio practices, such as limiting the number of
open microphones, minimizing the distance between sound source and microphone,
positioning the microphone and loudspeaker to get minimum feedback, and
balancing the room to get a flat response, is the first step in setting up a
good audio system. Later, we can adopt feedback suppression to get additional
gain. Feedback suppression cannot be used to magically solve a system’s design
defects or improve the sound transmission gain in a way exceeding the system’s
physical limitations. The feedback suppressor module automatically detects and
inhibits audio feedback in the sound system. The module distinguishes feedback
from expected sounds based on the characteristics of the audio signals. When
feedback at a certain frequency is detected, a notching filter will be
automatically added at the feedback point (frequency) to attenuate the signal
level at that frequency. During the first addition, the notching filter only
attenuates the feedback a bit. If the feedback persists, the notching filter
will continue to attenuate the feedback in accordance with the preset
parameters until the feedback disappears or reaches the maximum preset
parameter. Multiple user parameters can be used for accurate fine tuning of
the effects of the feedback suppression module. The Feedback suppression
filters may be locked up to prevent any change during operation.
Alternatively, the filter settings can be copied to a dedicated notching
filter module (such as the parametric equalizer). The Eight filters can be set
as auto filters in an automatic cycle. In this way, those filters for
temporary use can be removed. Each input channel has a feedback suppression
module. Use a mouse to navigate the input module and find the feedback
suppressor module or quickly enter the feedback suppressor module by clicking
the shortcut key on the right. If the feedback suppressor module needs to be
enabled, activate the module to automatically detect the feedback point, and
use a narrow-band filter for elimination. Each feedback suppressor module has
8 narrow-band filters.
The feedback suppressor module has the following adjustable parameters: Panic
Limiter Threshold: According to this parameter, any level higher than the
threshold is absolutely “feedback”. When a signal level is higher than the
feedback threshold, any of the following circumstances will occur; a) the
output gain is temporarily attenuated to control the speed of feedback; b) the
output level is restricted to prevent out of control feedback; c) the filter’s
sensitivity is increased for faster detection and feedback. Once the output
level is lower than the threshold, the gain will be recovered, and the
sensitivity is restored to normal state. This value refers to the peak value
of the digital range signal. If the value is set as 0, this function is
disabled. Feedback Threshold: According to this parameter, “any level lower
than the threshold is absolutely not feedback”. This may prevent the module
from detecting feedback in a soft music or due low noise level. Filter Depth:
It refers to the maximum attenuation of a single filter. A shallow setting may
prevent excessive frequency or signal degradation caused by the notching
filter to the original signal. A deep notching filter may cause worse feedback
control, especially in a large narrow resonance system.
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Bandwidth: 1/10 and 1/5 Oct options can be chosen. A constant Q value is
adopted. The filter will not become wider due to the increase of depth. It is
recommended to use the filter in the phonetic environment. In the case of
frequent feedback, the bandwidth is set at 1/5 Oct because it has wider
bandwidth and greater influence. Notching Filter Mode: Each notching filter
has two modes: Dynamic, or manual mode. When `Dynamic’ mode is set for the
notching filter and with all eight filters in use, the feedback suppression
module will “check” the dynamic filters and re-use an available filter to
inhibit the new feedback detected. When Manual mode is set for the filter, the
gain and frequency is manually set by the user. Clear All: Click the button to
instantly clear all filters. It will clear up all feedback points detected
previously. This operation is generally done when recommissioning the feedback
module. Feedback suppression can be used as a tool during system commissioning
to identify feedback points or as a preventive measure during normal
operations. If you want to get higher system transmission gain and feedback
suppression, it is recommended that you debug the system by following the
steps below:
(a) Reduce the system gain, and use the “Clear” button to reset all filter
parameters (b) Set up fine-tuned parameters for the feedback suppressor
module. Also, decrease the panic threshold to reduce the feedback level. (c)
Open all microphones, and slowly increase system gain until feedback occurs.
Stop increasing system gain when the feedback occurs. (d) Wait for the
feedback suppressor module to take effect; after the feedback disappears,
continue to increase gain. (e) Repeat the operation until the system reaches
the requiredgain or until all filters are fully distributed (f) Change the
panic threshold to a maximum level just higher than the expected non-feedback
signal.
At this time, if needed, you may set Fixed mode for each filter or save the
dynamic status to deal with possible feedback during the normal operation.
Additionally, you may copy the filter to a notching filter module (such as the
equalizer). In this way, you may add more feedback filter capacity. If a
speaker is included among the devices used, it is recommended to use a
compressor / limiter module for additional protection. You may set an
appropriate limiter to make sure that the speaker will not get damaged even if
all notching filters are used up, or the feedback inhibitor cannot effectively
control the feedback, such as in the case of excessive system gain.
3.4.8 Noise Gate
The main purpose of a noise gate is to attenuate signals below the set
threshold, and to allow signal to pass normally when the signal level is above
the set threshold.
Threshold: Audio signal greater than the threshold setting is passed while
audio signal less than the threshold is attenuation
Depth: The Depth determines how much the audio signal below the threshold is
attenuated. Attack time: Attack time refers to the time for the noise gate to
open after the threshold has been passed. Release time: The release time is
opposite to the attack time and refers to the time taken for the noise gate to
close. Hold time: The hold time determines how long the noise gate remains
open after the signal has dropped below
the threshold.
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3.4.9 Ducker
A ducker is used to attenuate or cut the level of the channel based on signal
level from a secondary signal input or channel. When the level of the
reference channel exceeds the specified threshold, the level of the specified
channel will be attenuated, in essence `ducking’ the signal level.
Threshold: The reference signal begins to decay above the threshold and
recovers below the threshold. Depth: The amount the signal is reduced by when
the ducker is activated. Attack time: Attack time refers to the time taken for
the attenuation to activate after the threshold has been
passed. Release time: The release time is opposite to the attack time and
refers to the time taken for the attenuation to
be released after the threshold is no longer passed by the reference signal.
Hold time: The hold time determines how long attenuation remains after the
signal has dropped below the
threshold.
3.4.10 Ambient Noise Compensation (ANC
An ambient noise compensator is used to automatically adjust output volume
according to a reference signal input. When the reference signal increases or
decreases with changing ambient noise picked up by a reference microphone, the
output volume of the specified channel can be increased or decreased based on
the set parameters.
Maximum gain: Sets the maximum amount to which the signal level can be
adjusted.
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Minimum gain: Sets the minimum amount to which the signal level can be
adjusted. Gain sensing ratio: Sets the ratio by which signal level is
attenuated or gained. Speed: The speed at which the signal level is attenuated
or gained. Trim: The amount of gain or attenuation the output signal is
adjusted by. Noise threshold: The threshold / mean dB at which the ANC will
activate and adjust signal. Signals greater than
the threshold will be increased, while signals less than the threshold will be
reduced. Distance: The physical distance between reference signal and local
signals.
3.4.11 Auto Mixer
In a conference room, if several microphones are opened to the same gain level
and there is only one person speaking, the audio pickup of the microphone may
be not clear. Other microphones will pick up noise and reverberation in the
room. When these signals are mixed with the desired speech’ signals, audio output quality may be greatly reduced and become un-intelligible. In addition, the whole audio signal chain may be over energized by excessive gain and could start feeding back, result in a feedback loop, or
ringing’ sound. To solve
the issue, other unused microphones should be closed or `muted” when not in
use. The auto mixer is used to automatically open and close microphones based
on signal input level. There is a built-in gain share auto mixer inside the
processor. It supports up to 8-channels. There is also a direct output at each
channel of the auto mixing matrix, which is only influenced by channel mute
and bypasses the auto mixer functions like auto gain and channel fader.
Channels suitable for fixed volume like background music need to be kept at a
fixed level without being controlled by the auto mixer. For example, it will
keep a microphone normally open. Its gain will then not be influenced by the
auto mixer. At this point, users may directly adjust the output of the channel
in the matrix router as well as turn off the auto mixer button of the channel.
Its gain will not be adjusted and gains at other channels will not be
influenced by the signal level at the channel. There are two groups of control
parameters in the auto mixer module: main control parameters and channel
control parameters.
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(1) Main (Global) control parameters
Click the ON / OFF button to turn the auto mixer on or off.
Gain: Controls the main output volume of the auto mixer
Slope: The slope control influences the attenuation of lower levels. If the
slope is high, the attenuation of lower-level channels will rise. The slope
control and the ratio control at the expander has the same working mode. It is
suggested that the value be set at or around 2.0. If it is set at 1.0, the
effect is equal to closing the auto mixer at all channels. If it is set at
3.0, the action will result in larger gain adjustment, which may bring
unnatural volume levels. The bigger the value, the more the channel is opened
and the more the total attenuation. When the slope is set at 2.0, ideal gain
sharing may be realized, so it is the preferred value to use.
Response Time: Faster response time may ensure that the first letters of
spoken words are not cut off. Slower response time allows smoother operation.
Practice shows that the best effect will be produced when response time is
between 100ms and 1000ms. The design of auto gain aims for faster microphones
switching. Therefore, first letters of spoken word will not be cut off even if
the response time is set to 100ms. If it is set at several seconds, then there
will be a longer hold time of the response time of the auto mixer, previous
active channels will be saved at open status for several seconds.
(2) Channel control parameters
Auto Mixer: Each channel has an auto mixer on / off button which must be
turned on for that channel to participate in the auto mixer. When in Off mode,
that channel will not participate in the auto mixer.
Mute: Both the channel mute and volume fader are post the auto gain processor.
If the channel level is higher, the level gain of other channels may also be
reduced even if the channel mute is on.
Gain: The Gain fader adjustment may increase / decrease the volume amount of
that channel in the auto mixer.
Priority: Priority settings may give priority treatment to high priority
channels over low priority channels, and therefore the auto mixer algorithm
will be affected accordingly. Priority ranges from 0 to 10. The higher the
value, the higher the priority.
Both the channel mute and fader are post auto gain. Any adjustment made
towards these two parameters won’t influence the operation of the auto mixer.
For example, If the channel level is higher, the level gain of other channels
may also be reduced even if the channel mute is on. Channel mute must be
turned on and the auto mixer shall be turned off to set signal mute and
prevent its influence on the auto mixer. The mute button at each channel and
directly controls output mute when mixing sound. Channel faders also control
sound mixing level and direct output level of channels. Click the textbox and
input a dB value to control channel level precisely. Priority control allows
high priority channels to override low priority channels, and thus the auto
mixer algorithm will be affected. Priority value can be set from 0 (the lowest
priority) to 10 (the highest priority), and the default value is 5 (standard
priority). Users may use the slider or click the textbook to input a specified
priority between 0 and 10. Increasing the value means increasing priority.
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If two channels have the same signal level, then the channel with higher
priority will receive more auto gain. If there is one-unit difference in
priority level between them, then the channel with the higher priority level
will get an extra gain of 2dB (supposing the slope of the two channels are set
at 2.0). For example, if channel 1 and 2’s priorities are respectively set at
6 and 3, and the input level of those two channels are the same, then Channel
1 will receive 66dB gain more than Channel 2. During operation, please note
that the slope setting of the main control parameters influence gain
difference brought by the priority weight of channels. If the slope is set at
3.0, then one priority level difference will result in a gain difference of
4dB.
Note: In some cases, be very careful when using wide priority differences
between channels, such as a priority of 0 and 10. If channels with ultra-high
priority recognize signals like background music from a loudspeaker, then it
is possible for them to mask channels with lower priority. The effect will get
worse if the slope is higher too. If the issue occurs during installation and
commissioning, users may consider installing a noise gate or expander between
the auto mixers of the highest priority channels. Also, consider setting a
threshold at a value that it won’t be opened by the noise gate or expander.
3.4.12 Acoustic Echo Cancelation
Acoustic Echo Cancelation (AEC for short) is used in audio / video
conferencing to facilitate full duplex communication. The AEC module increases
the remote speaker’s phonetic intelligibility by cancelling out or removing
unwanted acoustic echo generated in the local room’s audio system (between the
microphones and speakers). Echo cancellation module for remote calls can be
used to carry out local amplification of remote voice signals and attenuate
the interference caused by acoustic echo. Its basic operation principle is
simulating echo channel, estimating possible echo generated by remote signals
and then minus the estimated signal from input signal of microphones, and thus
there will be no echo generated in input voice signal to achieve the goal of
cancelling echo. There is only one echo cancellation module in the DSP
Controller. Two local inputs and remote output mixers are preset to realize
multichannel signal participating in echo cancellation as shown in figure. One
parameter can be adjusted, namely the Non-linear filter (NLP). There are three
preset filters to choose from: Conservative, Moderate and Aggressive can be
selected to determine the acoustic echo suppression level.
Note: The settings of the Acoustic Echo Cancellation module can be used
cooperatively with the matrix module to determine signal routes.
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3.4.13 Noise Suppression
The Noise suppression module is used to remove non-human voice interference
noise. It may distinguish human voice from non-human voice and treat the
latter as noise. After processing, only human voice audio signal is passed to
the output routing. There is only one Noise Suppression module in the DSP
Controller. Multichannel mixers are preset to realize multiple channels to
participate in the noise cancellation processor as shown in the below figure.
Suppression level: There are three levels of noise suppression including: Mild
(-6dB), Medium (-10dB) and Aggressive (-15dB). dB here refers to the reduction
in decibel level of the suppressed noise. The bigger the value, the more
degradation of voice signal is caused, therefore use noise suppression very
cautiously.
3.4.14 Matrix
The audio Matrix has dual functions including routing and mixing. As shown in
the figure below, the horizontal axis indicates the input channels, and the
vertical axis indicates output channels. One-to-one routing of input to output
is set as the default settings. As an example, to mix and route audio signals
of channel 1 and channel 2 and then output both select OUT1 on both IN1 and
IN2. If input 1 and 2 participate in auto mixing, then output 1 will not be
influenced by the auto mixer. In other words, after setting auto mixing, echo
cancellation and noise suppression modules, routing needs to be set in the
matrix from the correct input sources, like auto mixer, AEC, or ANS to get the
correct signal routing.
3.4.15 High and Low Pass Filter
Each output channel provides a pass-through filter module which consists of
high-pass and low-pass filters. Each filter has four parameters to adjust as
follows: Frequency: This sets the cutoff frequency of each filter. The cutoff
frequency of Bessel and Butterworth are selectable in -3 dB steps, and the
cutoff frequency of Linkwitz-Riley are selectable in -6dB steps. Gain: The
Gain setting influences the increase and attenuation of each filter band.
Type: There are three types of filters to choose from; Bessel, Butterworth,
and Linkwitz-Riley. Butterworth has the flattest knee on the passband.
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Slope: Slope refers to the attenuation values of the transition zone of the
filter. There are a total of 8 attenuation values including 6, 12, 18, 24, 30,
36, 42 and 48dB/Oct. For example, 24dB/Oct indicates that the attenuation
range is -24dB for each octave of frequency in the transition zone. Select the
On / Off button to activate or deactivate the high-pass or low-pass filters
individually.
3.4.16 Delay
The Delay module is used to add delay to the output audio signal. This can be
used to align audio signals in physical time.
Activate button: Turns On / Off the delay module and inserts it into audio
signal path to increase fixed delay time for signals. Millisecond (ms): Sets
the delay time in milliseconds. The value ranges from 1 to 1200 milliseconds.
Both meter and feet are alternate units provided to milliseconds to set a
delay time based on physical distance.
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3.3.17 Output
Phase: 180-degree audio signal phase inversion. Mute: Set output mute/unmute.
Users can use right button to set part menu at output channels, which can be
carried out based on requirements.
3.4.18 USB interface
The USB interface is used to carry out two functions, recording and as audio
interface for unified Communications using personal computers. After going
through echo and noise cancellation modules, the USB interface may be accessed
by unified communications software when connected to a computer.
Song playing information, double click to enter playlist Next song Pause Song
volume adjustment Play Prev. song Sound recording list Sound recording volume
adjustment Stop recording Start recording
Soundcard Setting USB cable with double ends of Type-A can be used to connect
DSP processor and computer host. For initial connection, the “Found New
Hardware” windows will pop up on the computer screen, and the driver will be
installed automatically. After installation, the USB soundcard will be
accessible in the computer soundcard list as shown in the figure below. Users
may select `Cretone USB Soundcard’ in the Sound Settings panel of the computer
for both Playback and Recording.
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Users may also playback audio files loaded manually in the on-board playlist from the connected computer. Users
may also directly open them when using the device next time. As shown in the figure, click at the bottom of the
playlist to open file folder and select the audio files to be played, press the settings of the USB interface.
to clear the playlist and to enter
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3.4.19 Camera Tracking
Voice tracking threshold: Detects a microphone input signal greater than or
equal to the tracking threshold, the system will automatically enable tracking
parameters when threshold is exceeded. Default Mic: When no Mic input signal
is received or tracking threshold is not exceeded, turn the camera to the
default MIC position Reaction time: The maximum intermittent time of the valid
signal. If the microphone is used to speak, the reaction time is set to 3
seconds, and the signal is still considered to be valid for 3 seconds in the
middle of the speech, and more than 3 seconds, is regarded as invalid. Scroll
time: The shortest speaking time required for the camera to switch to a valid
position. If the microphone is used to speak, the speaking time must be longer
than the “scroll time “. When the channel signal is considered to be valid,
the camera automatically turns to the set position. Usually “Scroll time” is
greater than “Reaction time “. Interval: Sets the interval between each camera
command sent. Sending Times: Sets the number of times a camera command is
sent.
Mic No.: Sets the microphone number; generally corresponding to the input
channel of the device. Priority: Sets the priority for the selected Mic No.
(channel). If two microphones / channels activate at the same time, the higher
priority level will execute the preset command. *Preset number, serial port
number, camera address and protocol, must correspond to the actual connection
of the camera. Enable: Turn enable on to enable the selected channel to form
part of the Voice Tracking Camera control.
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Save: Save the parameters to the device Camera Settings The camera settings
section is used to set up the control parameters for each camera connected.
Multiple cameras can be added, controlled and presets assigned accordingly.
3.5 Settings Menu
3.5.1 File Menu
In offline mode, click the pop-up file dialog and open an existed default
document with suffix *.uma, or right click on the default document to open
DSP.exe. “Save as” refers to saving presets on the application to local hard
risk to realize easy copy and store.
3.5.2 Device Setting
Information like device name, network address and serial baud rate can be set
under device setting. The maximum length of the device name is 16 characters.
Default startup: Two startup preset modes are available for selection. One is
any preset from 16 presets acting as startup preset. Each boot will start with
it. Another is selecting previous upload preset and taking the last preset
before power outage as the preset for next startup.
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3.5.3 GPIO Setting
Open the software interface of GPIO settings. The device has total 8 GPIOs
that allow independent input or output configuration. Input GPIOs have
preset,router, gain, mute, command, and analogue-to-digital gain as control
options. Output GPIOs have preset, level, mute, and command for selection as
control options.
Input GPIO Setting Preset
Routing
Trigger types: High level trigger, Low level trigger, High level trigger / Low
level trigger cancellation, Low level trigger, High level cancellation,
i.e., rising edge / falling edge trigger / rising edge trigger, falling edge
cancellation / falling edge trigger, rising edge cancellation
Preset: It will change to preset when jump type of hardware GPIO port and
trigger type of software setting are consistent.
Trigger types: Same as above
Input and output: Select input channel routing corresponding to output
channel.
Executes mixing / cancel mixing action when the trigger condition is
satisfied.
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Gain
Mute/ Unmute
Command
Analogue-todigital Gain
Output GPIO Setting Preset
Trigger types: Same as above Channels: Select input or output channels Step:
Level increase / decrease in 0.1dB steps based on original channel gain.
Trigger types: Same as above Channels: Select input or output channel
Trigger types: Same as above Command: The command code will be sent via RS232
when the trigger condition is satisfactory
Analogue-to-digital gain is very useful when connecting a potentiometer
externally. It may adjust input or output channel gain. It looks like a rotary
encoder. The difference between them is that a potentiometer is analogue and
adjusts voltage and current while an encoder is digital and transmits binary
codes of 0 and 1.
Output types: High level / Low level Preset: Corresponding GPIO port outputs
high level or low level when changing to it.
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Level
Output types: High level / Low level
Channels: Appointed input or output channel
Level: GPIO outputs high / low level when appointed channel level reaches
preset level threshold.
Mute
Output types: High level / Low level
Channel: Appointed input / output channel. Preset high / low level is output
when the channel is muted. On the contrary, the opposite level will be output
when cancelling mute.
3.5.4 Group Setting
The interface for group assignments contains two sections including input and
output labels. a Maximum of 4 groups are available. A channel can only
participate in one group. In each same group, the channel volume adjustment
and mute are synchronous. Other module parameters are not synchronized, which
is the biggest difference between the Group assignments and the stereo `Link’
option.
There are 4 groups in total. 1-device maximum number of channels can be
selected for each group. The maximum number of channels is determined by the
device type you purchased. Channels are set into one group which will be
differentiated by a color difference of the volume slider in the main
interface.
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ALF-DSP88-U
Group vs. LINK The relationship between groups and link: The channel
participating in a group will not participate in a `LINK’, which means group
priories are higher than LINK. The difference between Groups and LINK is that
Groups can only control channel gain and mute, while LINK links all parameters
at the channel.
3.5.5 Panel Setting
Panel setting includes two panel types which are an 8-button panel with Volume
control and an OLED panel. Use virtual cables to connect multiple physical
online panels with the online DSP device via panel settings, to configure the
panels for controlling selected DSP features.
Offline device: In offline edit status, the commissioning engineer configures
the panel parameters locally, and then downloads it to the online panel. The
panel can then be edited directly online. Drag an offline device from the
column of online panels to the panel design area and then double click to edit
it. Please note that there is a small circle on both panel and device. Click
the circle and then draw a line, select target device, the connection
betweenthe two devices is established this way. Double click the panel in
design area to enter the panel’s configuration interface. The configuration of
the two panels are described below. After completing configuration, click the
toolbar download icon to download the panel configuration to the hardware
panels. OLED Screen: The OLED screen consists of a 1.3″ OLED screen and Rotary
encoder. The OLED screen display is organized according to the function
assigned. There are three types of functions including menu, buttons, and
presets. Double click the OLED screen in the design area to enter its setting
as shown below.
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ALF-DSP88-U
Click “add menu” to access the pop-up menu selection box, choose the
corresponding function and confirm it. After finishing the settings of the
software menu configuration, click on the toolbar download icon to download
the configuration to the hardware panel. Operating the panel: 1. The panel
displays name and IP address on main interface. Turn the Rotary Encoder left
or right to change menus. 2. Press the Rotary Encoder to enter and display the
second row of the menu. The interface starts to flash, which indicates that it
entered edit mode of that menu. 3. Turn the Rotary encoder left or right to
change value. 4. Press the Rotary Encoder again to exit the edit mode and go
back to the main menu. Key Panel: There are eight keys and one Rotary Encoder
on the key panel. The Rotary Encoder is used to adjust gains, and the eight
keys can be used to achieve different functions through programming. There are
four types of key functions, including volume adjustment, mute, preset, and
command. Drag an item into the function area to assign the key and complete
the programming steps of the key. After completing all programming, users may
use the emulation button to check the configuration of the panel is correct.
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ALF-DSP88-U
Panel operation and Indicators: 1. Button remains illuminated, indicating that
it is configured with a mute function. 2. Button keeps flashing, which
indicates that the button is configured with gain function. The configured
Rotary Encoder adjusts the gain of the assigned channel. 13 indicators around
the Rotary Encoder indicates gain level. They are on or off with gain level
set. When all 13 indicators are off, it indicates a gain of -72dB while all on
indicates a gain of 12dB. 3. A momentary flash when pressing the button
indicates the button is configured for preset or command recall. Command
functions datastrings comes from the central control command. Please refer to
section 5 – Control.
3.5.6 Dante Setting
Note: Before accessing Dante settings, please check that the computer network
port and Dante network port of the DSP has been connected to the Dante
network. On the DSP software interface, you can only check the signal
indicator of the Brooklyn card. In order to set up a device lock or to check
the signal indicators, please use Dante Controller. Dante routing is also set
up in Dante Controller. Dante Controller provides routing, channel
information, network settings and other Dante network related information. The
Dante devices receiving channels are displayed on the left part of the
interface, while the Dante devices transmitter channels are displayed on the
top part of the interface.
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ALF-DSP88-U
On the routing interface, the small boxes at the intersection of the
transmitter and receiver channels indicate that a routing relationship can be
created. A green tick icon will appear at the intersection of the matrix after
a single click and once routing has been negotiated and a successful
subscription is established. Users may see a grey icon for a very short time
period while negotiating, which indicates that routing is in process.
A warning icon , or error icon will appear if there is a routing or
subscription problem. If several devices are subscribed at the same time, a
yellow icon may appear temporarily.
Note: Routed and locked devices cannot be moved, but existing routing can be
deleted, or replaced.
Cancelling Audio Subscriptions
Users may click on a subscribed intersections to cancel audio subscriptions.
The subscription icon will be removed, and a blank intersection block will be
displayed.
Subscription Status
Processing
Subscription is in processing
Subscribed
Connection established
Warning
Subscription is not processed normally because the transmitter device is not visible on the network
Error
Transmission error, for example, not enough bandwidth on the network
Coming soon
The device is processing subscription of other channels. In most cases, many channels are subscribed at once.
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ALF-DSP88-U
Users may view information like a device’s IP address and Dante firmware
version on the Device config’ tab. Double click device name on routing interface to enter detailed settings of the device as shown in figure below: Channel names can be modified on the transmitter and receiver labels. Channel naming rules are as follows: The maximum total length for all DSP device names is 16 characters. The name length of devices supported by Dante is as much as 31 characters. Therefore, ensure that the name length of Dante device names and channel names are no more than 16 characters when routing by using the interface, or the DSP Controller will cut the process off, which will result in incorrect subscription. Names are not case-sensitive. “Guitar” and “guitar” are the same name. Valid characters include A-Z, a-z, 0-9, and
-‘. Device
names can’t start or end with -‘. Device names shall also be unique on network. Any characters can be used for naming sending channel labels, except
=’, ‘ ‘and `@’. Sending channel labels must be unique in the device. Receiver
channel naming has the same rules as transmitter channels. Device
Configuration: Device configuration refers to device name modification, audio
sample rate, and delay. Device names must be modified following the device
name modification rules. Delay needs to be emphasized. If Dante network delay
compensation is needed for various delays at receiving end, there is device
setting delay (the interface delay) at each receiving end. The delay refers to
the time difference between samples received at the receiving end and
broadcasted from the transmitter end. The default delay for Dante devices are
1ms, which is adequate for largescale networks.
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ALF-DSP88-U
However, automatic negotiation will be carried out at sending and receiving
ends when establishing connections, which ensures delay time is negotiated to
prevent packet loss. For example, Ultimo devices support minimum 1ms delay. If
the delay for a faster device like a PCIe card is set at 0.25s and the device
is establishing connection with an Ultimo device, then the delay of
subscription will be 1ms which is the minimum delay supported by
subscriptions. If minimum delay possibly reaches 1s in a megabyte network,
then a subscription error may occur when transmitting based on the condition
that delay time is no more than 1s. Network Configuration: Network
configuration refers to network IP address, mask, and gateway settings.
Brooklyn supports redundancy mode and exchange mode settings. Redundancy Mode
Many Dante devices have two network ports named “Primary” and “Secondary”.
“Primary” port connects the physical network. If “Secondary” port has been
used, then “Secondary” port shall connect to another physical network. The
“Secondary” port cannot communicate with the “Primary” port.
Multicast Stream: What is stream? Dante audio routing automatically creates
streams. A stream moves audio data of several channels from transmitter ends
to one or more receiving ends. Unicast streams are given to single receiving
devices while multicast streams are given to multiple receiving devices.
Multicast streams may be created or configured manually through the interface,
but it uses network bandwidth whether there is receiving device or not.
Meanwhile, it doesn’t need extra bandwidth when more receiving ends are added.
As shown in the figure, select the multicast stream label page, check device
channel, click create, and then created multicast stream will display in the
right list of the interface. It can also be deleted when users don’t need it.
A stream mostly includes four channels by default. If more than four channels
are checked, they will be divided to several streams automatically.
3.5.7 Help Menu
(1) Central command
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ALF-DSP88-U
Open the central control command window and select the parameter to be
controlled on the DSP GUI interface. The window will display the current
command immediately. Copy the command and then use UDP or RS232 to send the
command to the device form external control interface. (2) Device upgrade
Device upgrades can be carried out through UDP. Connect the device, click
setting-help-device upgrade. A file choice pop-up box will appear, navigate
to, and choose the processor upgrade file (*.bin). Execute the update. (3)
About Display version number, tech support contact information and copyright
info., etc.
4. Control
4.1 External Control Programmer
The External control programmer supports UDP and RS232, and controls protocols
for all control parameters of the processor, including module parameter
controls, parameter acquisition, and preset calling. When UDP controls are
used, the default port is 50000. Ports can be set in “Device Setting” in the
DSP software. When using RS232 controls, the default baud rate is 115200, data
bits is 8, stop bit is 1, and parity set to None’. Similarly, they can be set in “Device Setting”. The interval between messages must be more than 100ms for RS232 command sending. If central control needs feedback and acknowledgement, please turn on
central control response’ in “Device Settings”.
4.2 Control Protocol
Because of historical reasons, the latest control protocol adopts variable-
length and is fully compatible with old fixed-length control protocols. In
protocols, the fourth byte is used to distinguish versions. 0- indicates V1
version (previous versions)and 1- indicates V2version (current protocol
version).
The difference between V1 and V2 is that V1 may control all processing module
parameters, but one command can only control one parameter. If a parameter is
needed to control continuous multiple channels, then V2 version must be used.
In other words, in a condition that users need to press one key on the key
panel to trigger GPIO output high- / low-level of devices, or send a command
via RS232 / RS485, then V2 version will be the best choice.
Software coding rules (total 12 bytes)
byte1
byte2
byte3
byte4
byte5~132
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ALF-DSP88-U
0xb3
Message
Length
Version
Data
Type
No.
V1: Information types (byte2): There are three information types including 0x21 (parameter controls), 0x22 (parameter acquisition) and 0x13 (scenario switch). Length (byte3): invalid. 0x21 (parameter control): Data byte 5 thought 12 are respectively:
byte 5~6
byte 7~8
byte 9~10
byte 11~12
Module ID
Parameter Type
Parameter 1
Parameter 2
Please refer to Appendix A to get the distribution of Module ID (byte 5 ~ 6).
Please refer to Appendix B for Parameter types (byte 7 ~ 8).
When Parameter 1 (byte 9 ~ 10) has only one parameter, then only parameter 1
is valid, such as control compressor switch.
Parameter 2 (byte 11 ~ 12) only valid when there are two parameters, such as
control output channel 1 mute. Parameter value 1 shall be filled in input
channel number from 0. Parameter value 2 shall be filled in 1 (mute).
Exception: Matrix routing has three parameters. The first one is input channel
number, the second one is output channel number, and the third one is routing
switch. At this point, byte 9 of parameter value 1 shall be filled in input
channel numbers, byte 10 shall be filled in output channel number, and
parameter 2 shall be filled in routing switch.
0x22 (Parameter Acquisition):
Parameter acquisition rules are the same with parameter controls. The
difference between them is values acquired shall be filled in parameter 1and
parameter 2.
0x13 (Scenario Switch):
Users only need to fill scenario numbers (0~ 15) in byte 5 and 0 in byte 6 ~
12.
Note: Central control command of V1 version can acquire code through software
menu bar of PC. For customized development, please use this protocol rule.
V2:
Message types (byte 2): There are three message types (byte 2) including
0x21parameter controls), 0x22 parameter acquisition), 0x13(scenario switch),
0x74 (other controls), and 0x6e (Dante routing).
Length (byte 3): Fill in corresponding data section length based on
information type. The length can be longer when actual sending is carried out.
Total data volume can be found through adding 4 byte header information to
data length. 1. Parameter Control (0x21) At this point, the formats of data
section are as follows.
Byte 5
Byte 6
Byte 7
Byte 8
Byte 9 ~ 72
Input / Output
Start Channel
End Channel
Parameter Type
Parameter Value
Byte 5: It indicates control input or output channel, 0x2- input channels and
0x1-output channels
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ALF-DSP88-U
Byte 6 – 7: They indicate start and end channel numbers. Channel numbers start from 0. Byte 8: This kind of parameter is the same with V1 version. Please refer to Appendix B. Byte 9 – 40: Fill in parameter values of start to end channels. It shall be filled in from the ninth byte. Each parameter value shall take two bytes. 2. Parameter Acquisition (0x22) Data section format is the same with parameter controls. Parameter values may not be filled in. Acquired parameters will be filled in this position. 3. Scenario Switch (0x13) Byte 5: Fill in scenario numbers (0- 15). Byte 6 – 8: Fill in 0. 4. Other Controls (0x74) Other controls include but not limited to GPIO, RS232, RS485, and central control replies. The protocol formats are as follows: GPIO:
Byte 5
Byte 6 Byte 7 Byte 8 Byte 9
Byte 10
Byte 11
Byte 12
Control Type
Data Length
Reserved Reserved GPIO Direction Start GPIO
End GPIO
Value
The controlling type for Byte 5 is 1. The data length of Byte 6 is fixed as four bytes. Byte 9 GPIO direction, set input or output. Value 0 indicates input, and value 1 indicates output. Byte 10 – 11 start GPIO and end GPIO. DSP devices have eight GPIOs in total, which are indicated with number 0 – 7. Byte 12 is determined according to Byte 9 GPIO direction. The field shall be filled in high (1) / low (0) level for output settings. The field is a return field to read GPIO level value on devices for input settings. RS232 / RS485:
Byte 5
Byte 6
Byte 7
Byte 8
Byte 9 – 132
Control Type Data Length Reserved Reserved Data
Byte 5 is 2 for RS232 control, and 3 for RS485 control. The data length of Byte 6 refers to data length that shall be sent via RS232 / RS485 currently. Byte 9 – 132 shall be filled in data sent by RS232 / RS485. Central control replies:
Byte 5
Byte 6
Byte 7
Byte 8
Byte 9
Control Type Data Length Reserved Reserved Reply Switch
Byte 5 control type is 4. The data length of Byte 6 is 1. When Byte 9 is 1, it means turning on central control replies switch; and 0 means turning off replies.
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ALF-DSP88-U
4.3 Serial Port-to-UDP (RS232 To UDP)
DSP devices support RS232 translating into UDP. The protocol formats are as follows.
4bytes prefix 4bytes
2bytes
1byte
1byte
128bytes
UDP:
IP Address
Port
Data Length
Reserved
Data
After receiving the protocol format data packet, RS232 sends data in the
protocol to appointed IP addresses and devices at ports.
For example, when sending data “HELLO DSP” to device port 50000 of device
“192.168.10.22”, the protocol commands are as follows:
4 bytes prefix
4 bytes
2 bytes
1 byte
1 byte
128 bytes
0x3a504455′:PDU’
0x1610A8C0 0xC350
0x09
0x00
“HELLO DSP”
Application scenario: The function can be applied in scenarios when many central control hosts have no network port. As shown in the below figure, central control hosts translate network commands through serial ports to control any network device.
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ALF-DSP88-U
5. FAQs
1. How to restore factory setting? Connect the processor to a computer
through RS232 and run the serial port software (SecureCRT is recommended for
use). The default baud rate of the serial port is 115200, 8 data bits, no
parity check, and 1 stop bit. After connecting SecureCRT to the serial port,
long press to enter a terminal interface to reboot the computer and enter the
bootloader boot dialog box as shown in the below figure:
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ALF-DSP88-U
Command explanation: del config: delete configuration information, such as
network configurations like IP address. The device restores to default IP
169.254.20.227 after deleting. del scenes: delete preset. All 16 presets of
DSP devices restore to default values. del all: delete all sections except the
program. Note: There may be no echo after the installation of SecureCRT.
Please check settings under “Local echo” by going to Options->Session
Options->Enable `Local Echo’, as shown in the picture below.
Appendix A: Module ID Distribution
Module Name
ID
Module Name
Input source
299
Output Channel 1-32 High &
Low Pass
Input Channel 1-32 Expander
1~32
Output Channel 1-32 Equalizer
Input Channel 1-32 Compressor
33~64
Output Channel 1-32 Delayer
Input Channel 1-32 Auto Gain
65~95
Output Channel 1-32 Limiter
Input Channel 1-32 Equalizer
97~128
Input Channel 1-32 Feedback Inhibition
129~160
AutoMixer
161
Echo Canceller
Echo Cancellation
163
Noise Suppressor
Noise Suppression
165
Mixer
166
Output
295
System Control
296
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ID 167~198 199~230 231~262 263~294
162 164
ALF-DSP88-U
Appendix B: Module Parameter Types (1)
Module Name
Parameter Type
Description
Module Name
Parameter Description Type
Input
0x1
Source
0x2
Gain Mute
Output
0x10
0x11
Gain Compensation Link
0x3
Sensitivity
0x12
Channel Level
0x4
Phantom Power Switch
0x1
Gain
0x5
Signal Generator Type
0x2
Mute
0x6
Signal Generator
Frequency
0x3
Channel Name
0x7
Sine Wave Gain Size
0x4
Invert
0x8
Channel Name
0x5
Sensitivity
0x9
Invert
0x6
Gain Compensation
0x10
Gain Compensation
0x7
Link
0x11
Link
0x8
Channel Level
0x12
Channel Level
Expander 0x1
Switch
Delayer 0x1
Bypass Switch
0x2
Threshold
0x2
Millisecond
0x3
Ratio
0x3
Microsecond
0x4
Setup Time
Equalizer 0x1
Total Equalizer Switch
0x5
Release Time
0x2
Child Segment Switch Compressor 0x1
Compressor Switch
0x3
Frequency
0x2
Compressor Threshold
0x4
Gain
0x3
Compressor Ratio
0x5
Q Value
0x4
Setup Time
0x6
Type
0x5
Recovery Time
0x6
Gain Compensation
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ALF-DSP88-U
Appendix B: Module ParameterTypes (2)
Module Name
Parameter Type
Description
Mixer
0x1
Mixer Switch
0x2
Mixer Gain
High & Low 0x1 Pass
0x2 0x3 0x4 0x5 0x11 0x12 0x13 0x14 0x15 Auto Mix 0x1 0x2 0x3 0x4 0x5 0x6 0x7
0x8 0x9
High Pass Switch High Pass Type High Pass Slope High Pass Frequency High Pass Gain Low Pass Switch Low Pass Type Low Pass Slope Low Pass Frequency Low Pass Gain Total Mute Total Gain Slope Response Time Channel Auto Switch Channel Mute Channel Gain Priority Auto Mix Switch
Module Name
Parameter Type
Description
Feedback 0x1 Inhibition
0x2
Switch
Feedback Point Frequency
0x3
Feedback Point Gain
0x6
Preset
0x7
Clear
0x8
Panic Threshold
0x9
Feedback
Auto Gain 0x1 0x2
Switch Threshold
0x3
Target Threshold
0x4
Ratio
0x5
Setup Time
0x6
Release Time
Echo
0x1
Cancellation
0x2
Echo Cancellation Switch Echo Cancellation Mode
Noise
0x1
Suppression
0x2
Noise Suppression Switch Noise Suppression Mode
System
0x1
Control
0x2
System Mute System Gain
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ALF-DSP88-U
7. After-sales Service
Should you experience problems using the ALF-DSPXX-U/D, please note that any
transport costs of the equipment to the distributor are borne by the user
during the warranty. 1) Product Limited Warranty: The manufacturer warrants
that its products will be free from defects in
materials and workmanship for seven years, which starts from the first day of
purchase. Proof of purchase in the form of a bill of sale or receipted invoice
which is evidence that the unit is within the warranty period must be
presented to obtain warranty service. 2) What the warranty does not cover
(servicing available for a fee): Warranty expiration. Factory applied serial
number has been altered or removed from the product. Damage, deterioration, or
malfunction caused by:
Normal wear and tear. Use of supplies or parts not meeting product
specifications. No certificate or invoice as the proof of warranty. The
product model showed on the warranty card does not match with the product or
if the product had been altered. Damage caused by force majeure. Servicing not
authorized by the manufacturer. Any other causes which do not relate to a
product defect. Delivery, installation or labour charges for installation or
setup of the product. 3) Technical Support: Contact our after-sales
department.
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ALF-DSP88-U
8. Warranty
1.1 This limited warranty covers defects in materials and workmanship in this
product. 1.2 Should warranty service be required, proof of purchase must be
presented to the Company.
The serial number on the product must be clearly visible and not have been
tampered with in any way whatsoever.
1.3 This limited warranty does not cover any damage, deterioration or
malfunction resulting from any alteration, modification, improper or
unreasonable use or maintenance, misuse, abuse, accident, neglect, exposure to
excess moisture, fire, improper packing, and shipping (such claims must be
presented to the carrier), lightning, power surges, or other acts of nature.
This limited warranty does not cover any damage, deterioration or malfunction
resulting from the installation or removal of this product from any
installation, any unauthorized tampering with this product, any repairs
attempted by anyone unauthorized by the Company to make su ch repairs, or any
other cause which does not relate directly to a defect in materials and/or
workmanship of this product. This limited warranty does not coverequipment
enclosures, cables or accessories used in conjunction with this product.
This limited warranty does not cover the cost of normal maintenance. Failure
of the product due to insufficient or improper maintenance is not covered.
1.4 The Company does not warrant that the product covered hereby, including,
without limitation, the technology and/or integrated circuit(s) included in
the product, will not become obsolete or that such items are or will remain
compatible w ith any other product or technology with which the product may be
used.
1.5 Only the original purchaser of this product is covered under this limited
warranty. This limited warranty is not transferable to subsequent purchasers
or owners of this product.
1.6 Unless otherwise specified, the goods are warranted in accordance with the
manufacturer’s product specific warranties against any defect attributable to
faulty workmanship or materials, fair wear and tear being excluded.
1.7 This limited warranty only covers the cost of faulty goods and does not
include the cost of labor and travel to return the goods to the Company’s
premises.
1.8 In the event of any improper maintenance, repair or service being carried
out by any third persons during the warranty period without the Company’s
written authorization, the limited warranty shall be void.
1.9 A 7 (seven) year limited warranty is given on the aforesaid product where
used correctly according to the Company’s instructions, and only with the use
of the Company’s components.
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ALF-DSP88-U
1.10 The Company will, at its sole option, provide one of the following three
remedies to whatever extent it shall deem necessary to satisfy a proper claim
under this limited warranty:
1.10.1 Elect to repair or facilitate the repair of any defective parts within
a reasonable period of time, free of any charge for the necessary parts and
labor to complete the repair and restore this product to its proper operating
condition.; or
1.10.2 Replace this product with a direct replacement or with a similar
product deemed by the Company to perform substantially the same function as
the original product; or
1.10.3 Issue a refund of the original purchase price less depreciation to be
determined based on the age of the product at the time remedy is sought under
this limited warranty.
1.11 The Company is not obligated to provide the Customer with a substitute
unit during the limited warranty period or at any time thereafter.
1.12 If this product is returned to the Company this product must be insured
during ship ment, with the insurance and shipping charges prepaid by the
Customer. If this product is returned uninsured, the Customer assumes all
risks of loss or damage during shipment. The Company will not be responsible
for any costs related to the removal or reinstallation of this product from or
into any installation. The Company will not be responsible for any costs
related to any setting up this product, any adjustment of user controls or any
programming required for a specific installation of this product.
1.13 Please be aware that the Company’s products and components have not been
tested with competitor’s products and therefore the Company cannot warrant
products and/or components used in conjunction with competitor’s products.
1.14 The appropriateness of the goods for the purpose intended is only
warranted to the extent that the goods are used in accordance with the
Company’s installation, classification, and usage instructions.
1.15 Any claim by the Customer which is based on any defect in the quality or
condition of the goods or their failure to correspond with specification shall
be notified in writing to the Company within 7 days of delivery or (where the
defect or failure was not apparent on reasonable inspection by the Customer)
within a reasonable time after discovery of the defect or failure, but, in any
event, within 6 months of delivery.
1.16 If delivery is not refused, and the Customer does not notify the Company
accordingly, the Customer may not reject the goods and the Company shall have
no liability and the Customer shall pay the price as if the goods had been
delivered in accordance with the Agreement.
1.17 THE MAXIMUM LIABILITY OF THE COMPANY UNDER THIS LIMITED WARRANTY SHALL
NOT EXCEED THE ACTUAL PURCHASE PRICE PAID FOR THE PRODUCT.
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