MICpre60 is meant for recording studios where the
highest sound quality is demanded. It is ideal for
recording engineers that prefer the sound of an analog
mic preamplifier over digital ones.
inputs are Balanced Mic and Line. Output is Balanced
too. The microphone gain pot is replaced by a selection
of gain settings. Simply use a jumper to select a
gain to match the microphone in use. This is not as
convenient as using a rotary pot but the benefit is
superior performance. The gain ranges from 38dB to
63dB in five settings.
Noise at 60dB Gain
photo above left is the selector for the gain. Position
1 is the highest gain (63dB). Postion 5 is the lowest
at 38dB. When in use, select the gain to match your
source be it a microphone or a keyboard.
of the main concerns with a 63dB amplification is
noise. The photo on the right is with the Gain set
at 63dB. As can be seen, the noise level is only +/-
2mV. This is superimposed over my oscilloscope floor
noise which is at +/- 0.8mV. All inputs are shorted
to ground for this measurement.
schematic above is the full MICpre60. The mic input
is configured as Sziklai pairs, commonly known as
Complementary Feedback Pairs. It has similarities
with Darlingtons in that both exhibit high impedance.
the two Sziklai pairs are the pcb headers in place
of a potentiometer. Only one gain setting can be selected
with a jumper. The output is Balanced with a 10dB
gain at maximum. This is equivalent to the three red
leds lighting up above the 0dB in the mixer. In use,
the output should be adjusted for unity gain for optimal
power the MICpre60, check out our PSU15REG.
It is equipped with voltage regulators for +15V and
Balanced Mic and Line Inputs
Electronically Balanced Output
Input Impedance = 1.2K ohms
Line Input Impedance = 10K ohms
= 7.1" X 2.2" (180mm x 56mm)
Double Sided | FR4