Tube Tech MMC 1A MIC Preamp and DI and multiband compressor - Manual

Lydkraft ApS
Mose Allé 20, DK2610 Rødovre
Denmark
1
TUBE-TECH MMC 1A
Mic-preamplifier and Multiband Compressor
Description:
The TUBE-TECH Mic-preamplifier and Multiband Compressor MMC 1A is a combined
microphone and DI preamplifier, a separate balanced line input and a three-band optical
compressor intended for recording directly to any recording media.
Mic -preamplifier:
The microphone preamplifier consists of a microphone input transformer (with a static screen)
with a step-up of +10 dB, two dual tube preamplifiers with a stepped gain switch, with
10dB/step (+20 dB - +60 dB) giving a total gain range of +20dB to +70dB.
The microphone input is provided with a switchable -20dB attenuation (PAD), switchable +48V
phantom-power, a phase reverse and has swithable input impedance (600, 1200, 2400 Ohm).
The high impedance DI input is unbalanced and placed in the circuit directly after the input
transformer. The gain range for this input is +10dB to +60dB. When in use, the microphone
input is disabled.
A high pass filter for the microphone, DI and line input is switchable between off, 20 Hz
and 40 Hz.
All inputs have a common stepped gain switch with 2dB/step (-10dB - +10dB).
Compressor:
The signal is fed to the two x-over networks, each made with a single RC circuit thereby
preserving optimum summation of the three bands at the output.
The x-over frequency between the low band and the mid band is variable from 60Hz to 300Hz
or 240Hz to1200Hz and the x-over frequency between mid band and the high band is variable
from 1,2kHz to 6kHz.
The signals from the three bands are then fed to the three separate side chain circuits, each
common for left and right channel. After processing, the three signals are fed to a gain control,
separate for each band and thereafter summed and send to the output gain, controlling the
entire output level for all three bands.
The compressors are of the optical device type. It has controls for ratio, threshold, attack and
release.
(050610)