Heritage Audio MCM32 Rackmount 32-Channel Summing Mixer USED

Great condition, always well taken care of. One owner, only used in a professional recording studio. Some scratches on sides and top which will of course be hidden when the item is rackmounted. No box present.

The MCM-32 employs a unique configuration, offering 32 input channels arranged into 4 subgroups of 8. Each channel features center detent Pan and Fader concentric controls plus balanced insert and mute switches.

The insert send points always have the signal present, so they can be alternatively used as direct outputs for recording without additional patch bays.

Each group has its own stereo fader and balanced insert point and all 4 stereo subgroups are passively summed into the master bus. The gain is restored by means of a 1073 style class A, transformer coupled, mic preamplifier, featuring a total of 4 transformers (1 input one output in each channel). The master section is also provided with its own balanced insert point.

All connections on the back are made by DSUB 25 connectors following the Tascam protocol, with the exception of the master bus connections, which are by dedicated XLRs.

Vintage Sound and Low Noise
The smart summing topology employed in the MCM series of mixers allows for an impressive headroom and surprising low noise figure for a 20 channel, vintage topology mixer. Special care has been taken on improving crosstalk and self-noise figures from those on the vintage designs in order to accommodate the new MCM mixers into the digital era.
The transformer based class A output stage is able to deliver a full +26dBu output.

Controls Per Channel
ON: When pressed, the related input is added to the subgroup bus. When depressed, it's muted.
INS: Turns the insert on. The insert send always have the signal present, whilst pressing the INS switch activates the insert return input.
FADER: Attenuates the signal sent to the subgroup bus from unity to minus infinity. Fader all clockwise means unity gain, whilst 12 o'clock means an approximate 20 dB of attenuation. (Or -20dB of gain).
PAN: Places the signal within the stereo spectrum, left, center, right or any intermediate setting. The panoramic law follows a standard in which if a 0dB signal is hard panned, it is -3dB when center panned.
AUX SEND LEVEL / PAN: The aux sends are implemented on the blue concentric knobs below each channel. If AUX 1 and 2 are selected, inner knob is aux1 send and outer is aux 2 send, whilst having Aux 3 selected inner blue knob turns into stereo level and outer becomes pan.
PRE: Takes the aux signal from the channel PRE or POST Fader.
3ST: Chooses between AUX 1 and 2 or 3ST.

Master Controls
VU Meters: Measuring the average level at the master outputs. They are calibrated at 0VU = +8dBu.
Master Fader: Attenuates the Mix's output from unity to minus infinity. The control has a stepped feel for easy recall of settings. Fader all clockwise means unity gain, whilst 12 o'clock means an approximate 20dB of attenuation.
ON: When pressed, the output of the Master is sent to the Output connectors. When depressed, it is muted.
INS: Turns the insert on. The insert send always have the signal present, whilst pressing the INS switch activates the insert return input

Specifications
Channel Input Impedance: Greater than 20 Kohm.
Maximum channel input level: Greater than +26dBu
Maximum insert return input level: Greater than +26dBu
Maximum insert send level: Greater than +27dBu, able to drive 600 ohm.
Maximum output level: Greater than +26dBu into 600ohm.
Frequency response: 0.5dB 20Hz to 20kHz
THD + N: Not more than 0.07% from 50 Hz to 10 kHz at +20dBu output (22 Hz to 22 Khz bandwidth) into 600Ω.
Noise, all faders up, all subgroups in, measured at the main output, 22Hz to 22Khz: ~-80dBu