OMNITRONIC MP-60 (01) PDF Document

The OMNITRONIC MP-60 is a PA mono mixing amplifier with the following features:

• PA outputs for 70 V or 100 V PA speakers or for low-impedance speakers (4-16 ohms)

• 3 microphone inputs (6.3 mm jack) with separate level controls

• Microphone input 3 with adjustable priority circuit

• 3 line inputs (stereo RCA) with separate level controls

• 1 line output (stereo RCA)

• Chime, switchable

• Treble and bass control for the output signal

• 7-fold LED level display

• Master control for the output signal

• Fan-cooled

• Protection circuits with LED indication: over current, short circuit, turn-on delay

• Rack installation

The front panel of the OMNITRONIC MP-60 features several controls for operation:

1. Power on/off: Turns the unit on and off. The power indicator lights up when the unit is powered on.

2. Control LEVEL: This is the master control for the total volume of the amplifier.

3. Tone controls: A 2-way tone control for the output signal, allowing you to adjust BASS and TREBLE.

4. Controls MIC 1 to 3: Individual volume controls for the microphone inputs MIC 1 to 3.

5. Input PRIORITY MIC 3: This 6.3 mm jack is for connecting a dynamic microphone and has a priority function. When an announcement is made through this channel, the level of other signal sources is attenuated, increasing the intelligibility of the announcement. The attenuation level is set by the rear PRIORITY LEVEL control.

6. LED level meter: Displays the output signal level.

7. Controls LINE 1 to 3: Individual volume controls for the line inputs LINE 1 to 3.

8. Button CHIME: Press this button to release a chime sound, typically before an announcement.

9. LED FAULT: This LED lights up when a protective circuit is activated. It will be lit for a few seconds after switching on until the speaker outputs are ready, and also during operation if the protective circuit has switched off the speakers due to a defect.

10. Power LED: Indicates that the unit is powered on.

The rear panel of the OMNITRONIC MP-60 provides the main input and output connections:

1. Control PRIORITY LEVEL: Adjusts the attenuation level for other audio sources when the chime is released or when a microphone announcement is made via microphone channel 3.

2. Inputs MIC 1 and MIC 2: Two 6.3 mm jacks for connecting dynamic microphones.

3. Inputs LINE 1 to 3: Stereo RCA inputs for connecting units with line level signals, such as a CD player.

4. Output LINE: A stereo RCA output for connection to other line-level devices like a mixer or another amplifier.

5. Screw connectors for 70 V and 100 V speakers: Terminals for connecting PA speaker systems.

6. Screw connector for 4 to 16 Ω speakers: A terminal for connecting low-impedance speakers.

7. Common ground connection COM for all speakers: The common negative terminal for all speaker connections.

8. Mains cable: For connection to a mains outlet.

9. Clamping screw: For a potential ground connection.

10. Mains fuse 1 and 2: Fuse holders. Only replace fuses when the unit is disconnected from the mains, using fuses of the same rating and power specified on the rear panel.

The OMNITRONIC MP-60 is designed for 483 mm (19″) racks. Follow these guidelines for proper installation:

• Use a double-door rack where both front and rear panels can be opened. The rack should have a cooling fan.

• Ensure there is enough space around the amplifier for heated air to pass on and escape. Steady overheating can damage the device.

• Fix the amplifier with four M6 screws in the rack.

• If installing multiple devices, leave at least 1 unit (1 U) of space between them for air circulation.

• When mounting, place the heaviest devices like amplifiers in the lower part of the rack.

• Fastening the amplifier by the front panel screws alone is not sufficient. For safety, provide additional fastening using ground and side bars.

• If the rack is to be transported, fasten the devices additionally by connecting the rear brackets with the side or ground bars of the rack to prevent it from being pushed backward.

You can connect either PA speakers (70 V/100 V) or low-impedance speakers (4-16 Ω) to the OMNITRONIC MP-60. Installation should be performed by skilled personnel only, with the amplifier turned off.

1. For PA speakers (70V/100V):

Connect the speakers to the terminals COM (negative pole) and either 70V or 100V (positive pole). The total load must not exceed 60 WRMS, otherwise the amplifier may be damaged by overload.

2. For low-impedance speakers (4-16 Ω):

Connect the speakers to the terminals COM (negative pole) and 4-16 Ω (positive pole).

3. Polarity:

When connecting, always observe the correct polarity (positive and negative connections). The positive connection of the speaker cables is always specially marked.

The input impedance of the speaker systems should at least be the same or even higher than the output impedance of the amplifier.

Example for the calculation of speakers/impedance when using low-impedance speakers:

Follow these steps for proper operation of the OMNITRONIC MP-60:

1. To prevent loud switching noise, first switch on all other units of the PA system.

2. Before switching on the amplifier, turn the master control LEVEL and all input channel level controls to zero to avoid high volume at the start.

3. Switch on the unit with the power switch. The power indicator will light up.

4. Turn up the master control LEVEL so that the mixing ratio of the signal sources can be adjusted in an optimum way.

5. Adjust the desired volume ratio with the level controls of the channels LINE 1 to 3 and MIC 1 to 3. Turn the controls of any unused inputs to zero.

6. To improve the audibility of an announcement, use the microphone channel PRIORITY MIC 3. In case of an announcement via this channel, the level of the other channels is attenuated depending on the rear control PRIORITY LEVEL setting. After the announcement, the level of the other channels slowly returns to the original level.

7. Adjust the desired sound with the tone controls. The high frequencies (TREBLE) and low frequencies (BASS) can be boosted or attenuated. In the mid-position, the frequency response is not affected.

8. Adjust the final level of the total volume with the master control LEVEL. The 7-step LED row shows the output level; the red LED 0 dB must not light permanently. If it does, slightly turn back the master control.

9. To release a chime before an announcement, press the button CHIME. The level of the other channels will be attenuated based on the rear control PRIORITY LEVEL setting.

The protective circuits in the OMNITRONIC MP-60 prevent damage to the speakers and the amplifier. When a protective circuit is activated, the speakers are electrically separated from the amplifier, and the red LED FAULT lights up.

The FAULT LED will light up in the following situations:

• For a few seconds after switching-on, until the speaker outputs are ready for operation.

• In case of a short-circuit at a speaker output.

• In case of an over current.

If the red LED FAULT lights up during operation or if it does not extinguish after switching on, the amplifier must be switched off, and the cause of the fault must be removed.

Before cleaning, disconnect the OMNITRONIC MP-60 from the mains.

We recommend frequent cleaning of the device. Use a soft, lint-free, and moistened cloth. Never use alcohol or solvents for cleaning.

There are no serviceable parts inside the device except for the fuse. Maintenance and service operations are only to be carried out by authorized dealers.

If the fine-wire fuse of the device fuses, only replace it with a fuse of the same type and rating. Before replacing the fuse, unplug the mains lead.

Procedure:

Step 1: Unscrew the fuseholder with a fitting screwdriver from the housing (anti-clockwise).

Step 2: Remove the old fuse from the fuseholder.

Step 3: Install the new fuse in the fuseholder.

Step 4: Replace the fuseholder in the housing and fix it.

Should you need any spare parts, please use genuine parts.