contacta VLD1 Large Area Vehicle Hearing Loop Driver Installation Guide
- June 24, 2024
- contacta
Table of Contents
contacta VLD1 Large Area Vehicle Hearing Loop Driver
Specifications
- Product Name: Large Area Vehicle Hearing Loop Driver Software VLD1
- Release Date: June 2024
- Function: Enhances communication for passengers with hearing loss in transport vehicles
- Features: Class-D amplifier output stage, advanced DSP core
Product Overview
- The Contacta Large Area Vehicle Hearing Loop Driver [VLD1] enhances communication for passengers with hearing loss throughout transport vehicles such as buses and coaches. This dual-output driver powers phased array hearing loops with a Class-D amplifier output stage and an audio subsystem built around an advanced DSP core.
- This user guide provides instructions on how to setup and adjust the Contacta VLD1 using the provided software, available for download via the Contacta website at www.contacta.co.uk.
Installation
The software is provided as a standalone executable file. No installation
is required. Once loaded, follow the instructions on the screen to connect to
the VLD1 driver.
Software Operation
Once connected to the VLD1, the screen will display the driver’s current
settings and status. All functions become available. Any settings that are
altered are immediately applied on the driver and will be kept even after
disconnecting the GUI or power cycling.
System Connection
The Reset and Factory Reset section allows the VLD1 to be power cycled or
restored to factory settings.
Driver Information
The driver’s unique ID (UID) and the firmware’s CRC is displayed in this
section.
Load / Save Settings
The software can save all settings stored on the driver to a config file
which can then be used to load settings to the same or another driver without
manual changes.
Audio I/O
The VLD1 supports Input A/B/C (SPDIF) and Output A/B connections.
Enable Inputs
EN1 and EN2 inputs can be set to mute based on logic high or logic low
signals.
Masking Noise
This feature allows adding a pink noise signal to the output signal to mask
background noise at low levels (less than -32dB).Adjust the slider to the
desired level to utilize this feature.
FAQ
-
Q: How do I connect the VLD1 driver to my vehicle’s audio system?
A: To connect the VLD1 driver, use the provided software to select the appropriate COM port and click Connect to establish a connection attempt. -
Q: Can I manually edit the config file to change settings?
A: The config file cannot be manually edited. All settings need to be changed using the software provided.
Large Area Vehicle
Hearing Loop Driver Software VLD1
Software and Setup Guide June 2024
Product Overview
The Contacta Large Area Vehicle Hearing Loop Driver [VLD1] enhances
communication for passengers with hearing loss throughout transport vehicles
such as buses and coaches. This dual-output driver powers phased array hearing
loops with an Class-D amplifier output stage and an audio subsystem built
around an advanced DSP core.
This user guide provides instructions on how to setup and adjust the Contacta
VLD1 using the provided software, available for download via the Contacta
website at www.contacta.co.uk.
The operating software requires the following:
- PC running Windows 7 or a more recent version.
- NET Framework 4.8 Runtime. This is already installed on most Windows machines, but is also included with this software. It can be downloaded from Microsoft’s website if necessary.
- Device driver for handling the communication with the VLD1. This device driver will be installed automatically once a connection is made from the PC to the VLD1. This driver can optionally be downloaded from FTDI’s website: www.ftdichip.com
- USB type A to USB type B cable to connect the Windows PC to the VLD1.
- Screen resolution set to at least 1920×1080 with resolution scaling set to 100%.
The information in this document is subject to change without prior notice in order to improve reliability, design and function and does not represent a commitment on the part of the manufacturer. In no event will the manufacturer be liable for the direct, indirect, special, incidental or consequential damages arising out of the use or inability to use the product or documentation, even if advised of the possibility of such damages. This document contains proprietary information protected by copyright. All rights are reserved. No part of this manual may be reproduced by any mechanical, electronic, or other means in any form without prior written permission of the manufacturer.
Installation
The software is provided as a standalone executable file. No installation is required. Once loaded, the following screen will appear:
The only controls available at this point are “Refresh Port List” and “Connect”. Select the COM port to which the VLD1 driver is connected and click “Connect” to make a connection attempt.
Software Operation
Once connected to the VLD1, the screen will be populated with the driver’s current settings and status. All functions become available. Any settings that are altered are immediately applied on the driver and will be kept even after disconnecting the GUI or power cycling.
System Settings
The main categories on the software’s GUI (displayed and labelled on the
previous page) are as follows:
- System Connection [see page 7]
- Power Reset and Factory Reset [see pages 7-8]
- Driver Information [see page 8]
- Load / Save Settings [see page 8-9]
- Audio I/O Mode [see page 10]
- Input A / B / C (SPDIF) Settings and Indications [see page 11]
- Output A / B / C (SPDIF) Settings and Indications [see page 13]
- Enable Inputs Settings and Indications [see page 14-15]
- Masking Noise [see page 15]
- Test Signal Generator [see page 16]
- Driver Status and Health Information [see page 17]
System Connection
This section handles the USB connection.
- After connecting and powering up the VLD1, click “Refresh Port List” to display available COM ports.
- Select the correct port and click “Connect” to establish a connection.
- Pressing disconnect disconnects the USB connection.
If the incorrect COM port is selected, an error message appears. In this case,
verify you have selected the correct port and try again. “Connection Status”
indicates the state of the connection.
Reset and Factory Reset
The Reset and Factory Reset section allows the VLD1 to be power cycled or restored to factory settings.
- To power cycle the VLD1, select “Yes” in Cycle Power then press “Go”. The serial connection will be disconnected.
- To restore the VLD1 to its factory default settings, select “Yes” in the corresponding section followed by “Go”. The serial connection is disconnected.
Driver Information
The driver’s unique ID (UID) and the firmware’s CRC is displayed in this section.
Load / Save Settings
The software can save all settings stored on the driver to a config file. This can then be used to load these settings to the same or another driver without the need to manually change all settings.
- To save settings, select “Save settings from driver to config file”. Choose a name and location for the config file.
- To load settings, select “Load settings from config file to driver”. Choose a config file to apply these settings to the driver.
The following settings are stored in the config file:
- Audio I/O Mode
- Input A Function
- Input A/B/C Level Adjustment
- AGC A/B
- HPF A/B
- HF Comp A/B
- Loop A/B Drive Level
- EN1/EN2 Mute on High or Low
- EN2 Function
- Masking Noise Setting and Level
The config file cannot be manually edited to change settings and all settings need to be changed using the software instead.
Audio I/O
There are three modes to choose from.
-
Input A -> Output A, Input B -> Output – This mode routes Input A to Output A, and Input B to Output
B. AGC, HPF, HFC are controlled individually. -
All inputs -> Output A and B, no phaseshift – All inputs are routed together to both output A and
B, with no phase-shift added. Since all inputs are added together, AGC A, HPF A, and HFC A is now disabled, and all inputs are now controlled using only AGC B, HPF B, and HFC B. -
All inputs -> Output A and B, phaseshifted – All inputs are routed together to both output A and B, with a phase-shift added. Since all inputs are added together, AGC A, HPF A, and HFC A is now disabled, and all inputs are now controlled using only AGC B, HPF B, and HFC B.
Input A/B/C (SPDIF)
This section controls all input adjustments.
If a VLD1 with SPDIF input is connected, the GUI will detect that the driver
has SPDIF functionality and the slider will become available. It will then be
possible to change the SPDIF gain with the same options as Input A and B.
Input A Function – Choose “Line” for a line level signal, and
“Microphone” for a microphone input which enables the microphone bias.
Input A/B/C Level Adjustment – The slider controls each channel’s pre-amp
gain, from -12 dB to 35.25 dB.
- Select “On” for normal operation.
- Selecting “Off” mutes the corresponding channel.
- Selecting “On” again restores the previous level.
If the connection to the driver is lost for some reason (for instance if the USB cable gets disconnected), the input will remain muted upon connecting to it again and will have to be manually set to a correct level.
Input A/B/C Level – Three different level indicators are shown: “Low”,
“Good”, and “High”. For the AGC to work properly, the pre-amp gain must be
adjusted so that the signal stays in “Good”.
AGC A/B – Turns the Automatic Gain Control on and off. Ensure the input
signal is indicated to be “Good”.
HPF A/B – This feature removes low-frequency sounds from the hearing loop
when background noise such as air conditioners might impact users. Select
either 150Hz or 180Hz if required, or “Off” to turn off.
HF Comp A/B – Turns on the High Frequency Compensation, providing a
selection of 7 predefined filters.
Input / Output Levels – Provides diagnostic information for input and
output levels. These values are the internal raw values on the VLD1’s DSP
chip. For normal operation, they can be ignored. Instead, the level indicators
(Low, Good, or High) should be used.
Output A/B
DAC A/B Leve l – Indicates the level of the audio signal being fed to
each output channel’s DAC. This is the signal level after pre-amp gain,
processed by AGC, HPF, HFC, but before any Output drive level has been
applied. Make sure to keep it in the “good” range.
Loop A Drive & Loop B Drive – Sliders which control the drive level for
each output stage. If a slider is all the way to the left, the drive is at -57
dB which effectively mutes that channel. The output can be adjusted from -26
dB to 6 dB.
- Select “On” for normal operation.
- Select “Off” to mute the corresponding output channel.
- Selecting “On” again restores the previous level.
If the connection to the driver is lost for some reason (for instance if the
USB cable gets disconnected), the output will remain muted upon connecting to
it again and will have to be manually set to a correct level.
Loop A Current & Loop B Current – Indicates how many amps each loop
output produces, both visually and numerically. If voltage clipping is
detected, the “clipping” box changes from the green to red.
If you have a channel’s DAC level in “good”, and the Drive slider high enough
to expect a normal loop current, but instead you have a very low loop current,
this could be an indication that the loop is open circuit.
Enable Inputs
EN1 and EN2 inputs can be set to mute if the signal connected to these ports
are logic high or logic low (24V or 0V). EN2 can also change function to
either Mute All or to only Mute B + C (SPDIF).
In the “Mute and EN1/EN2 Status” the mute status of each input channel can be
seen, as well as high or low state for both EN1 and EN2.
In the picture above, EN1 is set to mute channel A on a Low signal, and since
we can see that EN1 is in a low state, Input A is now muted. EN2 on the other
hand is set to Mute All, but is in a High state, so channels B + C stay
unmuted. In the case when EN1 might say “don’t mute”, but EN2 says “mute”, EN2
takes priority and mutes all channels.
Masking Noise
This feature allows a pink noise signal to be added to the output signal.
This may be helpful in masking background noise at low level (less than
-32dB). It is not a cure for background noise and does not make levels above
-32dB acceptable.
To use this feature, select ‘on’ and adjust the slider to the desired level.
Test Signal Generator
This feature provides the required signals needed for setting up a loop,
negating the need for an external signal generator.
Selecting any of these settings bypasses the signal from the audio inputs.
The test signal generator will stay on until either “normal operation” is
selected or the driver is power cycled.
Driver Status and Health
This section displays any potential faults, as well as the internal power
supply’s voltage and internal temperature. If no faults are detected (as in
the image above) all indicate “no fault detected” on a green background. If,
however, a fault is detected, the colour changes to red and the fault is
presented.
General Fault – Indicates that there is a general fault in the system.
Contact your dealer if the problem persists, noting any error codes.
Output A/B Fault – This indicates one of the following faults:
- Ground Fault. See VLD1 Installation & User Guide for more information.
- Open Fault. See VLD1 Installation & User Guide for more information.
- Output Stage Error. A fault is detected, and the driver is trying to recover.
- Output stage held in shutdown. A fault has been detected, and the driver failed to recover. Correct the fault and power cycle the VLD1 either from the GUI or by disconnecting the power, and reconnecting it.
Local dealer
UK & ROW
+44 (0) 1732 223900 sales@contacta.co.uk
www.contacta.co.uk
US & Canada
+1 616 392 3400 info@contactainc.com
www.contactainc.com
References
- Innovative assistive technology solutions - Contacta
- Home - Assistive Hearing Technology & Solutions - Contacta Inc
- Home - FTDI