The board will have two inputs to receive the backbone or D/A converter return.
Monitoring of Stereo, Mono Sum and Difference.
Auxillary Output to Feed an A/D or Meter
10 or 20 dB Dim
Main and Alternate Outputs with Hard Cut and Power-On Delay
I've got the relay coil wiring to draw and will then be moving onto the layout.
That looks great. I could have used that instead of cobbling everything together from the M/S boards and some JLM boards. It’s perfect for a two turntable QC setup.
The only suggestion I’d make is to include meter offset capability.
Would you prefer that it be a trim, fixed R or jumper/switch for the meter offset?
I think fixed R with multiple possible positions. I'm thinking for digital mastering of loud mixes you would want attenuation. For using things like calibration records you would want gain. Both types specific calibrated positions.
What I think I might do is add an unbalanced dedicated meter output that is fed from the same selection as the Aux outputs.
I wanted to keep the Aux path short.
The meter output would have switch-selectable gain offset as well as a trim - similar to the PTS variable stage.
I'll do it if there is room on the layout.
I've got the board laid out and am checking it today.
I barely had enough board real estate to add the variable gain stage for the Aux Output Paul requested.
It's configurable for either +/-5.5 dB gain trim when used as a final A/D output or, with the addition of a simple switch, provides a -10 dB reduction for metering.
Other gain ranges are possible with resistor changes.
I've got the sch conformed to the board - I'm about to compare the layout to the sch using a high-lighter.
The schematics in the OP have been updated.
