Calibration for Mix bus compressor

[analogggman]

Does anyone here calibrate the mix bus comps?

 

[gyraf]

..which mix bus comps in particular?

I always calibrate things like the G10, 22 and 24..

 

[analogggman]

Yeah, any and all buses. Drums, Music, Master, etc. Just curious what your method is... 1k sin tone? 1d reduction? etc.

..which mix bus comps in particular?

I always calibrate things like the G10, 22 and 24..

 

[gyraf]

Depends very much on the exact circuit.. what are you asking for?

 

[TwentyTrees]

@analogggman - there are a couple of ways to understand your question. Are you asking about calibrating a bus compressor's circuitry so that it functions as expected (ratios, threshold, metering, THD, etc)?

Or is it more about calibrating the levels in your overall signal chain, so that bus compression is predictable (eg 0VU in your DAW is +4dBu in your analogue insert chain, at which point your bus compressor is set to give 1dB of gain reduction on a 1kHz test tone)? If the latter, then sort of - my levels & metering are all set and consistent, but the compressor settings and level of gain reduction vary a bit depending on the track.

Or have I misunderstood completely?

 

[My3gger]

Only levels and filters for solid state mix bus compressor, meaning parts of the circuit are matched between channels. Good example would be taking GSSL block schematic and match parts ch A to parts ch B. VCA distortion can also be trimmed.
Tubes circuits require more work; matching tubes for one channel, then also match them between ch A and ch B (not easy for vari gm tubes), same for filters and other parts. Layout is important too, more so p2p due to many high impedance parts and limited space, although i might be a little too worried about layouts.
Others will know a lot more about the circuit you are asking for.

 

[Script]

Yeah, any and all

Yes, all stages from input to output.

 

[analogggman]

@analogggman - there are a couple of ways to understand your question. Are you asking about calibrating a bus compressor's circuitry so that it functions as expected (ratios, threshold, metering, THD, etc)?

Or is it more about calibrating the levels in your overall signal chain, so that bus compression is predictable (eg 0VU in your DAW is +4dBu in your analogue insert chain, at which point your bus compressor is set to give 1dB of gain reduction on a 1kHz test tone)? If the latter, then sort of - my levels & metering are all set and consistent, but the compressor settings and level of gain reduction vary a bit depending on the track.

Or have I misunderstood completely?

Yeah you are correct. The 1k test tone trick is one I am asking about. Michael Brauer does that and then mixes into his compressors. I was just curious how other people in this forum are doing it.

 

[Duster]

I’ve tried to do this with MB’s method but I couldn’t really make it work. I’m probably missing something crucial. Through trial and error I’ve just set my buss compressors so they hit the sweet spot when most of the faders are more or less around unity. Of course they vary cause it’s a mix but just so most of the faders are more or less in a moderate range of the throw of the fader when they trigger the compression. I never have to adjust the buss comps now. I just mix into them. Of course you have to have consistent level coming in to your tracks or it won’t work. Is there something I am missing about his method? Do you calibrate before every mix?

 

[Script]

For my part, I still don't understand really what's being asked. Sounds like gain staging of chained studio gear and recording levels. Anyone care to give a link of some sort to MB method ?

As for fine-calibrating gear circuitry itself would measure AC (audio path) and DC (supply, bias, control). For digital need a scope.

 

[zamproject]

I was just curious how other people in this forum are doing it.

At my side, the bus comp (VCA) is calibrated for nominal level at master insert.

For the -average- or most common setting I start with the comp (which have a 4000 side chain topology)
threshold @ 0, ratio @2:1, 10msATT and 600 or more for REL, the comp start to work at 0PPM (1k test tone)

Then I adjust TH and makeup regarding what the song request, and those settings can evolve during the session especially as the bus comp is ON at the very beginning of a mix.

So in practice this is just a coarse help, approximatively giving an average sweet spot, as a visual feed back (GRM) of my overall dynamic.

At the technical side, the calibration is done at higher level, like +10dB over nominal level, and comp trimmed to read +5dB over nominal (for a 2:1 ratio) with threshold at 0.
GRM setting is done after that to read 5dB, knowing that dynamic programme (non test tone) will overshoot the meter ballistic...

 

[Whoops]

Depends very much on the exact circuit.. what are you asking for?

I'm also quite confused about what the OP is asking...
Analogggman, you should explain yourself better