M0070 Professional Preamp User Guide 1.0
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©2009 Microlynx Systems Ltd.
Adjustable Input Gain
The input gain control can be used to boost or cut the input signal by up to 6 dB. For best noise
performance it should be set to the maximum level that doesn’t cause clipping. If this level is too high
for your amplifier, it can be backed off.
Low Battery and Clipping Indicator
The M0070 has an easily visible red LED that flashes if the signal gets close to clipping level. The gain
should be set so that the LED only occasionally flashes. There is still at about 3 dB of headroom before
clipping actually occurs.
If the LED is constantly illuminated, the battery is low and should be replaced. If you use a quality
alkaline battery, there will still be at least three hours of usable life left after the light first comes on.
Operating instructions
Operation of the M0070 professional preamp is simple and intuitive. Please read and follow these
instructions to get the most out of your preamp.
Installing and changing the battery
Carefully remove the screws at either end of the preamp and gently lift the top cover. Install the battery
in the holder, making sure to observe the correct polarity. Slide the battery forward until it engages in
the holder. Replace the top cover, with the serial number sticker at the bottom. Carefully insert and
tighten the screws. Do not over
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tighten.
Installing the Preamp on your instrument
For ease of use we strongly recommend mounting the preamp under the tailpiece of your instrument.
To protect your instrument and avoid rattling, place the supplied strips of felt on the top and bottom of
the preamp at both ends. Place the preamp under the tailpiece and use two of the tie wraps to attach
the preamp to the tailpiece. Tighten the tie wraps until they are snug but do not over tighten.
Use a short phone patch cord to connect the transducer to the input of the preamp.
Powering the preamp
The M0070 only consumes power if a ¼” mono phone plug is inserted in the phone output, or if
phantom power is supplied to the Direct Out.
To conserve battery life, always unplug the output when not in use.
Setting the gain
Plug a phone cord into the output of the preamp. The red LED will flash briefly to indicate that the
preamp is being powered.
Look at the red LED while playing your instrument as loudly as possible. Ideally the LED should barely
flicker.
If the LED is on for extended portions of your playing, reduce the gain by turning the Gain potentiometer
counter clockwise using a small screwdriver.
