MX1280 - Receiver OSD Audio - Free user manual and instructions

Type	Multi-Zone Receiver/Amplifier
Brand	OSD Audio
Model	MX1280
Channels	12
Power Output (per channel)	80W RMS into 8 ohms
Total Power	960W RMS
Frequency Response	20 Hz - 20 kHz ±0.5 dB
Total Harmonic Distortion (THD)	<0.05%
Signal-to-Noise Ratio	>90 dB
Input Impedance	47 kOhms
Speaker Impedance	4 - 8 ohms
Inputs	12x RCA line-level, 2x optical, 2x coaxial
Outputs	12x binding post speaker outputs, 12x RCA line-level outputs
Zone Control	Independent volume and source selection per zone
Remote Control	IR remote included
Dimensions (WxHxD)	17.0 x 3.5 x 12.0 inches (432 x 89 x 305 mm)
Weight	22 lbs (10 kg)
Power Supply	120V AC, 60Hz
Power Consumption	1200W max
Maintenance	Clean with a dry, soft cloth. Do not use solvents.
Safety	Do not expose to rain or moisture. Unplug during storms.
Spare Parts	Contact OSD Audio customer service for replacement parts.
Reparability	Service by qualified technician only. No user-serviceable parts inside.

Frequently Asked Questions - MX1280 OSD Audio

How do I connect speakers to the MX1280?

Use the binding post outputs on the rear panel. Strip 1/2 inch of insulation from each speaker wire, insert into the terminal, and tighten the knob. Ensure polarity (+/-) matches.

Can I use the MX1280 with a 70V distributed audio system?

No, the MX1280 is designed for standard 4-8 ohm speakers. For 70V systems, use a separate step-down transformer or a dedicated 70V amplifier.

What is the maximum number of zones?

The MX1280 supports up to 12 independent zones, each with its own volume and source control.

How do I reset the MX1280 to factory settings?

Press and hold the 'Reset' button on the rear panel for 5 seconds while the unit is powered on. All settings will return to defaults.

Does the MX1280 support Bluetooth?

No, the MX1280 does not have built-in Bluetooth. Use an external Bluetooth receiver connected to an RCA input for wireless streaming.

What is the recommended amplifier for outdoor speakers?

The MX1280 is suitable for outdoor speakers as long as they are rated for outdoor use and have an impedance of 4-8 ohms. Ensure proper weatherproofing of connections.

How do I troubleshoot no sound from one zone?

Check that the zone is not muted, the source is selected, and the volume is turned up. Verify speaker connections and that the speaker is working. If using a remote, ensure batteries are fresh.

Can I bridge channels for more power?

No, the MX1280 channels cannot be bridged. For higher power per zone, consider using an external amplifier with the line-level outputs.

What type of remote control is included?

The MX1280 includes a full-function IR remote that allows control of power, volume, source selection, and zone settings.

Where can I download the user manual?

The user manual is available for free download on notice-facile.com in PDF format.

USER MANUAL MX1280 OSD Audio

MX SERIES MULTI ZONE 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.

IMPORTANT SAFTEY INSTRUCTIONS

1. Read these instructions.
2. Keep these instructions.
   3 Read all warnings.
   4 Follow all Instruction.
3. Do not use this apparatus near water.
4. Clean only with dry cloth.
5. Do not block any ventilation openings. Install in accordance with the manufacturers instructions.

6. Do not install near heat sources such as radiators, heat registers, stoves, or other apparatus (including amplifiers) that produce heat.

7. 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 plugs does not fit into your outlet, consult an electrician for replacement of the obsolete outlet.

8. Protect the power cord from being walked on or pinched particularly at the plugs, convenience receptacles, and at the point where they exit form the appliance.

9. Only use attachments or accessories specified by the manufacturer.

10. Unplug the apparatus during lightning storms or when unused for long periods of time.

11. Refer all servicing to qualified personnel. Servicing is required when the apparatus has been damaged in anyway, such as power supply cord or plug is damaged, liquid has been spilled or objects have fallen into the apparatus, the apparatus has been exposed to rain or moisture, does not operate normally, or has been dropped.

Introduction

The OSD Audio MX Series Multi-Zone Amplifiers are ideal for adding additional power in distributed audio applications or combining with home theater systems. The MX880 provides 8 channels, MX1280 provides 12 channels and MX168 provides 16 channels of digital amplification. All MX Series models incorporate features such as bridge mode operation, global and independent zone triggering, audio sense circuitry with delay time per zone, two Bus Inputs/Outputs and independent line inputs per zone to meet the wide range of audio applications and projects. All MX Series amplifiers are rated at 50 watts per channel into 8 ohms and 80 watts per channel into 4 ohms. With the Stereo/Bridge switch in Bridge mode, each zone of channels are combined for a higher powered mono output of 160 watts into 8 ohms. With high performance and ultra-low distortion output, the MX series Multi-Zone Amplifiers provide unmatched sound quality for any audio system.

Thermal Protection

All MX series amplifiers are designed with special circuitry to safeguard the amplifier under a thermal overload condition. Thermal protection mode will only engage when the unit has been run at high volume for extended periods of time without adequate ventilation and/or when speaker impedances are below the minimum levels for the amplifier. In thermal protection mode the amplifier will automatically stop output. If this fault occurs, turn off the amplifier, and check that the speaker impedance rating is above the minimum rating. Also check for adequate ventilation around the amplifier and make adjustments if necessary. Once the unit has cooled to sage operating temperatures, the amplifier may be powered back on.

Protection Circuitry

Special circuitry has been designed into the MX Series Multi-Zone Amplifier to safeguard under a short-circuit condition. A faulty speaker can also cause a short circuit condition. The Zone LED indicator will blink rapidly between red and blue. If this fault condition occurs, turn off the amplifier and check speakers for short circuit conditions when appropriate.

Installation

The MX Series Multi-Zone Amplifiers can be placed on a shelf, as part of an equipment rack, or on a table or cabinet. During installation, keep in mind that the amplifiers require proper clearances for ventilation and heat dissipation. The amplifier will take two rack spaces with the feet removed.

Front Panel

1. Power/Standby LED
   This LED lights red when any zone is active or the amplifier is in standby mode.
2. Zone LED
   Blue: the corresponding zone is powered on.
   OFF: the corresponding zone is off (standby mode).
   Red/Blue: A short circuit happens on the speaker outputs

Rear Panel

1. Bus 12VDC Trigger In/Out
   The Bus 12VDC Trigger In is used to activate all zones that are using the Bus Input and disables other zone triggers or signal sensing on those zones when it is used. While the Bus12VDC Trigger is used, all Bus-controlled zone LEDs will be blue and active. If the Bus Trigger In has 12V applied to it, only the 12V Bus Trigger Out will have 12V and the Zone Trigger Outputs will not.
2. Bus Inputs/Outputs
   The Bus Line Inputs are optional inputs that can be used to connect a single source to multiple zones. The Bus Line Outputs are passive pass through the corresponding of the Bus Inputs and can be used to daisy chain the source to other amplifiers in the system.
3. Line/Bus Switch
   Switches the zone input to the Line Input, Bus Input 1 or Bus Input 2.
4. Line Input
   The Line audio input for each zone is a dedicated sensing input that will activate the zone when an audio signal from a source is present.
5. 12VDC Trigger In/Out (Each Zone)
   The Zone 12V Trigger In is used to activate a specific zone.
   The Zone Trigger Out can be used to trigger other 12V devices. The delay and audio sensing are bypassed when the 12V Zone Trigger Input is used. When a Zone Trigger inactive, the zone LED will be blue. If no voltage is present in the Zone Trigger, the Zone LED will be off. Standby Mode The amplifier will go into Standby mode when audio signal or trigger is not present after 3 munities.
6. Speaker Outputs
   The minimum speaker impedance is 4 ohms for Stereo Mode and 8 ohms for Bridge Mode.
7. Stereo/Bridge Switch
   Selects the output mode of each zone for stereo or Bridge operation.
8. Gain Controls
   Left and Right gain controls for each zone adjust the sound level independently. Only using Left control to adjust the sound level when used in Bridge Mode.
9. Voltage Switch
   AC 115V or AC 230V dual voltage selector.
10. AC Input
    Apply the correct voltage before operate the amplifier.

Specifications

Power Output:

80W /Channel, 1KHz into 4 Ohms, One Zone Driven

50W /Channel, 1KHz into 8 Ohms, One Zone Driven

160W, 1KHz into 8 ohms, Bridge

Amplifier Channels:

MX 880: 8 Channels, 4 Zones

MX 1280: 12 Channels, 6 Zones

MX 1680: 16 Channels, 8 Zones

Signal-to-NoiseRatio: >90dB A-weighted

Frequency Response: 20Hz to 20KHz + 1.7/-1dB at 1W output into 8 Ohms

Input Sensitivity: 600 mV for 80W @ 1 KHz 4 Ohm One Zone

700 mV for 50W @ 1 KHz 8 Ohm One Zone

Input Impedance: >22K Ohms Line Input

Trigger Inputs / Outputs: Bus and Zone @12VDC

Zone Line Input: Line In, Bus In 1, Bus In 2 select switch per zone

Bridge Mode: Select Stereo or Bridge mode per zone B Ohm only

Speaker Connectors: Detachable speaker terminals support up to 14awg wire

Delay Time: When audio signal or trigger is not present after 5 munites.

Power Requirements (Switchable):

MX880: 100-120VAC 60Hz 600W Max

220-240VAC 50Hz 600W Max

MX1280: 100-120VAC 60Hz 900W Max

220-240VAC 50Hz 900W Max

MX1680: 100-120VAC 60Hz 1200W Max

220-240VAC 50Hz 1200W Max

Fuse Rating:

MX 880: 100-120V/T5A, 250V

220-240V/T2.5A, 250V

MX 1280: 100-120V/T8A, 250V

220-240V/T4A, 250V

MX 1680: 100-120V/T10A, 250V

220-240V/T5A, 250V

Dimensions (L x W x H): 16.81" x 16.14" x 3.46"

Weight:

MX 880: 19 lbs.

MX 1280: 20.5 lbs.

MX 1680: 22.8 lbs.

System Configuration

Typical Mode

MX Series amplifiers can be configured as the main amplifier for an audio distribution system or home theater system. When used with an audio distribution preamp or matrix processor, each zone can independently drive one of several different sources by using each zone's individual line audio inputs. If the specify zone needs a higher power, please just use Bridged mode.

When MX 1260 or MX 1680 is working as a home theater amplifier, the amplifier could support up to a 7.1 or 5.1 surround system, and recommend using the Bridged mode to have the higher outputs.

Bridged Mode

When the amplifier is in Bridged Mode operation, a single channel (the left) is used to provide a higher power mono output. Use one channel pair to amplify the left channel by connecting the left audio signal to the L input of a channel pair, setting the Stereo/Bridge switch to "Bridge" and connecting the speaker as indicated below. Use a second channel pair for the right channel by connecting the right audio signal to the L input of a second channel pair, setting the Stereo/Bridge switch to "Bridge" and connecting the speaker as indicated above. Note: The three position switch needs to be set to "Line In" on both zones that are wired for Bridged Mode.

Wiring Instructions - Bridged Mode

• Turn off the amplifier and connect an 8-ohm minimum load.
• Set the Stereo/Bridge switch to Bridged Mode.
• Follow the Bridge mode markings on the back of the amplifier:
  Connect the negative lead (-) of the speaker cable to the R-terminal.
  Connect the positive lead (+) of the speaker cable to the L+ terminal
• Apply the Line In from audio source to the Left Line In connector.
  • Power on the amplifier.