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Meter Bridge Connector Pinouts

The 8-bus series of mixers provide connectors for connecting the Mackie 8-bus meter bridge. The connectors are 0.100" DIP header pinouts and are normally hidden under rubber removable plugs across the top of the mixer, just below the insert jacks. These pinouts were determined experimentally, using an oscilloscope, a multimeter, a 1KHz test tone source, and a small DIP20 to DIP20 header cable to make probing for signals easier.

[20 pin DIP header]

Channels (1-8, 9-16, 17-24, 25-32)

The channel strip audio signals appear to be 1.30V peak 0.92V RMS at 0dB reading on the meters with the channel soloed. This was determined with a 1KHz sine wave input to a channel strip line-level input. The channel was soloed, the fader set to unity gain, and the input trim adjusted to read 0dB on the VU meter.

Pin Function
1Tape Return 1, 9, 17, 25
2Tape Return 2, 10, 18, 26
3Tape Return 3, 11, 19, 27
4Tape Return 4, 12, 20, 28
5Channel Strip Post-Fader 4, 12, 20, 28
6Channel Strip Post-Fader 3, 11, 19, 27
7Channel Strip Post-Fader 2, 10, 18, 26
8Channel Strip Post-Fader 1, 9, 17, 25
9+18VDC
10-18VDC
11+5VDC
12GND
13Channel Strip Post-Fader 8, 16, 24, 32
14Channel Strip Post-Fader 7, 15, 23, 31
15Channel Strip Post-Fader 6, 14, 22, 30
16Channel Strip Post-Fader 5, 13, 21, 29
17Tape Return 5, 13, 21, 29
18Tape Return 6, 14, 22, 30
19Tape Return 7, 15, 23, 31
20Tape Return 8, 16, 24, 32

Output Section

The main Left and Right output signals appear to be +4dBu (1.23V RMS, 1.76V peak w/1KHz sine wave).

Pin Function
1Right Main Output
2Left Main Output
3NC
4NC
5+5VDC
6GND
7NC
8NC
9+18VDC
10-18VDC
11NC
12NC
13NC
14NC
15NC
16NC
17NC
18NC
19NC
20NC
 
 
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