Buzz Audio ma-2.2stereo microphone preamp - Manual (Page 5)

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3] Controls and Indicators.
• O … REV
Input phase reverse switch. In the up position the input is in phase
with the output. In the down position the input phase is reversed.
It is normal to hear a “click” when operating this switch.
•
0dB … -20dB
Input attenuator. In the up position the gain of the MA 2.2 is as
marked around the GAIN knob. In the down position, a pad is
inserted at the input, reducing overall gain by 20dB. Use for high
level inputs such as drums when you can’t turn down the GAIN far
enough. It is normal to hear a “click” when operating this switch.
•
PK
This led will light when the output of the MA 2.2 reaches +18dBu
indicating a possible overload condition. The MA 2.2 is capable of
+24dBu output level. The threshold of this indicator can be
internally adjusted, see the section on Internal Adjustments.
•
GAIN dB
Adjusts the gain/volume of the MA 2.2. What more can we say?
•
OUT … MUTE
This control mutes the MA 2.2 output when in the down position.
Very useful in avoiding loud “bangs” when you have to switch on the
phantom power or change the microphone input. Also read Tips.
•
48V … ON
Phantom power required for condenser microphones and active DI
boxes. In the down position, 48V is applied to pin 2 and 3 of the
input XLR connector via 6k8 ohm resistors.
CAUTION!! Always MUTE the MA 2.2 when switching the
48V on or off to avoid loud “bangs” and damage to your
loudspeakers and ears!!
•
HI Z … LO Z
This control changes the input impedance of the MA 2.2. The input
impedance is what the microphone “sees” as a load. In the up
position, the MA 2.2 input impedance is 3k ohms. In the down
position the input impedance is 1k2 ohms. Which position to use??
This is purely a subjective thing. Some microphones such as
dynamic and older tube types may sound better in the LO Z position.
It is normal to hear a “click” when operating this switch.
MA 2.2 USERS MANUAL VERSION-1 PAGE 4