OSD AUDIO MI4 Power Amplifier Owner’s Manual
- June 16, 2024
- OSD AUDIO
Table of Contents
MI4
Power Amplifier
OWNER’S MANUAL
WARNING
- TO PREVENT FIRE OR SHOCK HAZARD, DO NOT USE THIS PLUG WITH AN EXTENSION CORD, RECEPTACLE OR OTHER OUTLET UNLESS THE BLADES CAN BE FULLY INSERTED TO PREVENT BLADE EXPOSURE.
- TO PREVENT FIRE OR SHOCK HAZARD, DO NOT EXPOSE THIS APPLIANCE TO RAIN OR MOISTURE.
- TO PREVENT ELECTRICAL SHOCK, MATCH WIDE BLADE PLUG TO WIDE SLOT, FULLY INSERT.
The lightning flash with arrowhead symbol, within an equilateral triangle, is intended to alert the user to the presence of un-insulated dangerous voltage within the products enclosure that may be of sufficient magnitude to constitute a risk of electric shock to persons.
CAUTION
RISK OF ELECTRIC SHOCK DO NOT OPEN
Warning : To reduce the risk of electric shock, do not remove cover (or
back). No user serviceable parts inside. Refer servicing to qualified service
personnel.
The exclamation point within the equilateral triangle is ntended to alert the
user to the presence of important operating and maintenance (servicing)
instructions in the literature accompanying the appliance.
IMPORTANT SAFETY INSTRUCTIONS
- Read these instructions.
- Keep these instructions.
- Read all warnings.
- Follow all instructions.
- Do not use this appliance near water.
- Clean only with dry cloth.
- Do not block any ventilation openings. Install in accordance with the manufacturer’s instructions.
- Do not install near heat sources such as radiators, heat registers, stoves, or other appliance (including amplifiers) that produce heat.
- Do not defeat the safety purpose of the polarized or grounding type plug. A polarized plug has two blades with one wider than the other. A grounding type plug has two blades and a third grounding prong. If the provided plug does not fit into your outlet, consult an electrician for replacement of the obsolete outlet.
- Protect the power cord from being walked on or pinched particularly at the plugs, convenience receptacles, and at the point where they exit from the appliance.
- Only use attachments or accessories specified by the manufacturer.
- Unplug the appliance during lightning storms or when unused for long periods of time.
- Refer all servicing to qualified personnel. Servicing is required when the appliance has been damaged in anyway, such as power supply cord or plug is damaged, liquid has been spilled or objects have fallen into the appliance, the appliance has been exposed to rain or moisture, does not operate normally, or has been dropped.
This appliance shall not be exposed to dripping or splashing water and no object filled with liquids such as vases shall be placed on appliance.
Congratulations on your purchasing of OSD Power Amplifier.
Please take a few moments to read the entire manual, and be sure to retain
this document for future reference. Please read and observe all safety
instructions detailed on each page.
Note: If any part of this product is damaged or missing, please call OSD AUDIO Return Department at 562-697-2600
Using the controls/ Front Panel
Power
The POWER push button will manually switch the MI4 Power amplifier on or off. The blue LED beside the button indicate its power status. Whenever the amplifier’s power switch is on, the LED will illuminate blue.
OUTPUT ADJUSTMENT
The RIGHT VOLUME and LEFT VOLUME knobs are for individual adjustment of left
channel and right channel output.
The corresponding L/MAX and R/MAX LED show the output level status. when the
output is adjusted to reach clip, they will illuminate RED.
The BASS GAIN knob is used for adjust the gain of Bass for the output.
Using the controls/ Back Panel
INPUTS
There is a total of 2 pairs of RCA input on the rear panel of the MI4 Power
Amplifier. These RCA inputs are labeled as “Line 1″ and “ Line 2″. They are
also designed with an “R” and “L” as Right Channel and Left Channel inputs
respectively.
“Line 2″ Input should be used as the primary or normal input for various line
level sources that may be available locally to the amplifier. “Line 1″ Input
is a priority switching input that can be used for a second input, such as,
the output of a second source, and will take over as primary input whenever
the signal is present. If the “Line 1″ Input signal is absent after 12
seconds, the input will revert to the “Line 2″ Input signal.
The Line 2 has “OUT” RCA connectors to loop the Line 2 signal to other
devices.
The MI4 Power Amplifier also provides a pair of speaker level input labeled as
“Speaker In” for those applications where either of the sources has only
speaker level output signal available. The Speaker In signal will be mixed
with Line 1 or Line 2 input signal controlled by the switch labeled “Line 1″
and “Line 2″ as option on the right side of “Line 1″ Input RCA connectors.
This screwdriver adjustment knob labeled as “LEVEL” can be used to adjust the sensitivity of MI4 inputs from “MIN” to “MAX”.
OUTPUT
To the right of the Speaker Out connectors is a switch labeled :Mode” with
“Stereo” and “Bridged” as options. It is used to switch the output mode of
MI4.
If you will be connecting a pair of speakers to the amplifier, place the
switch in the “Stereo” Position. If you will be using a pair channels to power
a single mono speaker, place the switch in the “Bridged” position.
The MI4 Power Amplifier has 2 channels outputs. Each channel has a pair of
multi-way binding post connectors.
These are red and black screw posts on the rear panel of the amplifier.
Terminals are provided for “L” and “R” output. If you will use the amplifier
with a stereo mode(not a bridged mode), connect the speaker’s positive(Red)
terminal to the amplifier’s positive(Red) terminal using the appropriate gauge
speaker wire, and connect the speaker’s negative(Black) terminal to the
amplifier’s negative(Black) terminal(immediately beside the positive terminal)
using the appropriate gauge speaker wire.
If you would like to use the amplifier with “Bridged” mode, place the “Mode”
Switch in the “Bridged” Position to be a single channel mono amplifier, the
two channels will be internally connected in series. You will use both Red
terminals to connect to the speaker, the “L” channel’s Red terminal will be
positive terminal and the “R” channel’s Red terminal will be negative terminal
under “Bridged” mode.
Note: This amplifier will supply 130W in “Bridged” mode. Please verify that
your speakers are capable of handling such power to avoid possible damage!
Note: The minimum impedance for the total load connected to a pair of channels
in the “Bridged” mode is 8-ohm.
MI4 Power Amplifier Specifications
Power Bandwidth: 20Hz – 20kHZ
50W per Channel into 8 ohms loads with less than 0.05% THD+N
65W per Channel into 4 ohms loads with less than 0.1% THD+N
130W Bridged Mono into 8 ohms with less than 0.1% THD+N
Crosstalk: >60dB@1KHz, referred to rated power at 8 ohms
Frequency Response: (25Hz to 50kHz) +0dB, -1.0dB
Signal to Noise ratio: >98dB
RCA Line Input Sensitivity: 220mV (Max)
Speaker Input Sensitivity: 2.3V (Max)
AC Power Consumption:
Dimensions: 19″w x 7.87″d x 2.85″h,
“1.5U Option Rack Space Style”
Net Weight: 5.65 kg
Gross Weight: 6.25 kg
AC Mains Fuse:
115V~60Hz T3.15AL, 250V
230V~50Hz T3.15AL, 250V
360W (All Channels Driven)
NOTE : This amplifier is capable of use with standard US voltage (115V) as well as European voltage (230V). The amplifier will be preset for the voltage of the country it is sold in. Use with other voltages requires some changes to be made to the amplifier. Should you wish to use the amplifier in a country other than the one for which it was purchased, please contact OSD AUDIO at (562) 6972600.
Limited Warranty
OSD AUDIO: warrants its amplifier products against defects in materials and
workmanship for a limited period of time. For a period of two years from date
of original purchase, we will repair or replace the product, at our option,
without charge for parts and labor.
This limited warranty applies only to purchases from authorized OSD AUDIO
retailers. This limited warranty is extended only to the original purchaser
and is valid only to customers in USA.
Customers are required to provide a copy of the original sales invoice from an
authorized OSD AUDIO dealer when making a claim against this limited warranty.
This limited warranty only covers failures due to defects in materials or
workmanship that occur during normal use. It does not cover failures resulting
from accident, misuse, abuse, neglect, mishandling, misapplication,
alteration, faulty installation, modification, service by anyone other than
OSD AUDIO or damage that is attributable to acts of god. It does not cover
costs or transportation to OSD AUDIO or damage in transit. The customer should
return their defective product, freight prepaid and insured, to OSD AUDIO,
only after receiving a Returned Merchandise Authorization (RMA) number.
This warranty will become void if the serial number identification has been
wholly or partially removed, altered or erased. Repair of replacement under
the terms of this warranty does not extend the terms of this warranty. Should
a product prove to be defective in workmanship or material, the customer’s
sole remedies will be repair or replacement as provided under the terms of
this warranty. Under no circumstances shall OSD AUDIO be liable for loss or
damage,
direct, consequential or incidental, arising out of the use of or inability
to use the product.
Applications
Powering Speaker Outdoors
Whenever you are using speakers outdoors, you should be aware that sound
does not travel like it would be in your home. Without the reflective surfaces
of walls and ceilings, sound at outdoors will dissipate quickly.
Therefore, in an outdoor situation the MI4 Power Amplifier provides the
opportunity to bridge adjacent channels, effectively doubling the available
power for your speakers. This can help to overcome the problem of using
speakers outdoors assuming the speakers chosen are capable of handling the
additional power.
It should be noted that the MI4 Power Amplifier is rated to operate into
a minimum 8-ohm bridged load.
Therefore, if you are using more than a single 8-ohm loudspeaker in bridged
mode you should consider using an impedance matching speaker selector, such as
the SSVC-6 or possibly using an impedance matching volume control, such as the
SVC 70, SVC 100, SVC 300, VKR 120, VMS 100 or VMX 300 in a weatherproof
housing available at your favorite DIY store or electrical supply. The choice
of a volume control would allow you the additional flexibility of being able
to attenuate the volume whenever necessary.
Stereo Setup
In this configuration, the Mode switch is set to “Stereo” for stereo
operation. Connect the line out jacks from a stereo preamplifier or source to
the Line 2 Input jacks of your MI4 Power Amplifier. Then connect your speakers
to the output
Binding Post observing proper polarity(You can check “OUTPUT” on Page 4 for
reference about the polarity).
Mono Setup
In this configuration, the Mode switch is set to “Bridged” for Bridged operation. Connect the line out jacks from a stereo preamplifier or source to the Line 2 Input jacks of your MI4 Power Amplifier. Then connect your single mono speaker to the output Binding Post observing proper polarity(You can check “OUTPUT” on Page 4 for reference about the polarity).
Setup For Multiple Sources
In the application shown below, a distributed audio system is connected to the MI4 Power Amplifier as a local zone amplifier via the Line 2 Input. Normally the distributed audio system will be the audio source for the MI4 Power Amplifier. The distributed audio can be passed on to be used by additional zones or sub zones in the distributed system via the Line 2 Output.
The audio output of a local source, such as MP3 Player, CD, Television, computer, etc., is connected to the MI4 Power Amplifier via the Line 1 Input, and whenever the local source is active its signal will take priority over the distributed audio signal present at Line 2. However, the distributed audio signal will still be present at the Line 2 Input. In this circumstance the audio output of the local source will be heard via the MI4 Power Amplifier. Once the local source is turned off or muted, the MI4 Power Amplifier will automatically switch back to the distributed audio system as an audio source, assuming the local source remains inactive. The delay time is 12 seconds when switch back to the normal source will occur. This set up assumes all incoming signals are at line level and not at speaker level.
If the Whole House Distributed Audio was only available as a speaker level
signal you could connect it to the “Speaker In” connections and set the switch
which is on the right side of “Line 1″ Input RCA connectors to the “Line 2″
position or toward to the left hand position of the switch. The MI4 Power
Amplifier will no longer be able to pass the Whole House Distributed Audio to
another zone via the Line 2 Output.
If you have any questions regarding how to set this up, please call OSD AUDIO
support at 562-697-2600.
References
Read User Manual Online (PDF format)
Read User Manual Online (PDF format) >>