Martin Audio Operation, Martin Audio - MA1.3s Amplifier, English, Contents, Print, Guides

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Channel A and B into two separate	Channel A and B into one Speakon	Bridged mono
Speakons.	(Stereo and Bi-amp)

GUIDES

ENGLISH

Never connect either output terminal to ground or to some other output or input terminal (see warnings in chapter 1)

For normal two-channel operation, connect each speaker load across the output’s positive and negative terminals.

Pay attention to speaker polarity; loudspeakers connected out of polarity degrade sound quality.

Keep the loudspeaker cables as short as possible and use a good quality stranded cable. Do not use shielded wire, such as microphone or guitar cable. The loudspeaker cable reduces the power of the amplifiers in two ways:

It increases the load impedance and introduces resistive power losses.

WARNING: To prevent electric shock, do not operate the amplifier with any of the loudspeaker cable conductors exposed.

8 OPERATION

8.1Operating precautions

•Make sure that the power switch is set to “OFF” before connecting any input or output or operating the switches on rear panel. See pages 8 about installation.

•Make sure that the AC mains voltage is correct and the same as the one printed on the rear panel of the amplifier. See pages 8, about operating voltage and power consumption.

•Make sure that the operating mode switches on the rear panel, gain,link/ bridge, and clip-limiters, are in the correct position. See page 6 about operating modes, page 13 about clip limiters and 7 for the ML

•It is always a good idea to turn down the gain controls during power-up, to prevent speaker damage in case a high signal is present at the input.

8.2Powering up – Soft start

When you power up the amplifier it takes a couple of seconds to check its circuits. This is known as the "soft-start" or "slow-start" sequence. The fans then blow at high speed before going into "idle" and the two bottom green LED’s illuminate to show the amplifier is operational.

8.3Input attenuators

The two input level attenuators on the front panel adjust the signal level for their respective amplifier channel in all modes. They are calibrated in dB to help the setting up of active loudspeaker systems.

In bridged mode, both controls must be in the same position, so that the speaker load will be shared equally between the channels.

8.4Indicators

The two-bottom green ”ON” LED’s indicating that the output circuits are receiving the correct rail voltage.

The ”-40 dB” LED’s illuminate if the output signal is greater than -40dB (with 0dB as reference to full output power). These LED’s also act as signal present indicators.

All material © 2007. Martin Audio Ltd. Subject to change without notice.

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Martin Audio – MA1.3s Amplifier