Any FOH Engineers in the House? QC mixing question

When mixing a QC, where you do you normally set Gain and Comp on the board? Been using about 25% for each. Wanted to know if anyone else has thoughts.

Any kind of ā€˜standardā€™ gain setting makes no sense at all. All desks are different.

Proper method for setting gain for ANY source:

  1. Solo the channel (this should generally show you the input level on the main meters)
  2. Have the person in question make the loudest noise they are intending to make on that source.
  3. Adjust channel gain to have that channel peaking at around 0dB*

*for analogue desks, or for ā€˜analogue-styleā€™ meters on digital desks.
Essentially you want to have the loudest possible signal you can, without it ever being in danger of clipping. IF you later find you have the channel faders pulled way down because the source is too loud, itā€™s better to pull the gain down and keep the faders closer to unity.

Compression depends on many factors, but namely - style of music, tone of guitar, dynamics of guitar, room soundā€¦ If itā€™s a one knob comression control, just adjust it to taste.

4 Likes

I agree with the post above (though you donā€™t even need to solo the track if you have either a PFL switch/meter or a dedicated meter per track).

I usually start with Comp off and gain at the minimum possible setting (and pad in) and bring up gain so as to ā€œfill the channelā€ properly (ie hit yellow to light orange on level meters) to get the best possible signal to noise ratio.
So as a rule of thumb if your loudest presets output at around -18dB FS (per the Output meter on the QC) you should be safe.

Compression only happens if I feel the dynamic rangeā€™s too big and I need to better control it (so low signals arenā€™t as low and loud signals arenā€™t as loud). If your levels are properly staged on your presets and they donā€™t go from super soft to crazy loud, little to no compression is necessary (I usually donā€™t ever use compression on electric guitars, distorted sounds are pretty compressed as is anyway).

2 Likes

Makes perfect sense but our mixer doesnā€™t have a needle. Just a light that blinks when itā€™s clipping.

What about a starting point? Thatā€™s why I mentioned percentages rather than absolute positions.

Thanks for the reply. Iā€™ll turn comp off and see how it sounds. Usually the faders for my guitar are around -10 to -15 dB.

Yup, Iā€™ve levelled all my patches so they output the same level (except for lead).

Why do you engage the pad?

1 Like

So as to start from the lowest possible amplification factor (since itā€™s basically what the gain knob is for, and the pad switch allows you to toggle between different amplification ranges). Preamp gain is here to amplify signal as needed, as a rule of thumb I strive to mess with incoming signal as little as possible (might be a byproduct of doing jazz for a while now).
And having the faders around -10dB usually is fine, as they usually are logarithmic and thatā€™s about the spot where the taper gets flatter (hence moves are more precise).

1 Like

In that case, turn it up til the light flashes, then back off a bit until it stops. Sounds like itā€™s an analogue desk, so shouldnā€™t be too bad if you get the occasional clip. They tend to design them so that the clipping LED goes off before it actually clips too.

2 Likes

Both my setup at home (plain Jane behringer mixer ā†’ power amp) and at church on Sundays (PreSonus something or other) the gain for the channels (I run 2 channels and pan one completely left, and one completely right) is set at 0dB.

I run the rotary ā€œmaster volumeā€ knob on the QC at 100%. I just feel like it sounds truer and fuller to my ear.

This gives my FOH the whole range of the fader(s) to play with. They love it.

1 Like