Gain structure on sq6

[stratParticipant]

I recently purchased a sq6 console… so far so good, But I have realized that the channels either lack headroom or get to clipping really quick, when I was at a show over the weekend I noticed this problem, So I had the time to compare to my spare that I keep with me in case of a break down, It is a Behringer X product and had way more headroom and no clipping compared to the sq6, A friend of mine told me of the same issue with his sq6.
Any advice would be appreciated.

[Jens-DroesslerParticipant]

So? Just set the gain 6 to 10dB lower. Problem solved.

[stratParticipant]

Yeah right.

[AndrienParticipant]

How do you set up your gain structure? Btw behringer X series use Midas style preamp which afaik has unique properties when pushed even beyond clipping that it doesn’t break as easily. I’m not sure about the build in preamps on SQ tho as we used DX rack which have dLive preamps.

[stratParticipant]

At this show I set the faders @ 0 then set the preamps accordingly before any adjustments on the eq, at this point I had good signal .. mainly green with some occasional amber lights, But I sure could of used more volume .. and I use big powersoft amps .. so that is not the issue, Like I said the “X” Console had no clipping at all and had way more volume.

[stratParticipant]

I also use DX Rack

[EthanParticipant]

Aren’t you supposed to set the pre-amp gain to 0 then adjust the fader volume as needed? I don’t really have any problems with “head room” on our sq6. In fact, we had to turn down our power amps quite a bit after we switched from the ML4000 to the SQ6.

[GCumbeeParticipant]

My theory for 50yrs has been. Set gain so fader is in normal shaded area. See how that works as for no clipping. Adjust as needed. But you want the fader somewhere in that upper 3/4 area so you have a little level up and s lot down. Faders are usually not linear. They are logrhythmic. Once Setup you only adjust gain if needed. That’s not to say all faders will be at zero during the show. You will be moving them as needed but it’s important not to be too radical on either end of the travel.

[lightingman117Participant]

Strat,

At the risk of sounding brisk.

Make sure it’s out of the red, that’s it. There’s no secret sauce to gain structure. Console designers design for incorrect usage.

As far as the clipping is concerned, I think the SQ6 clips quite gracefully and doesn’t have audible distortion until it is deep in the red. Kinda/not really similar to Midas’/Behringers’ auto-gain reduction strategy at/near clip.

Perhaps this is an eyes (seeing meter levels) issue rather than an ears issue?

The peak light indicates at -3dBFS this gives you an indication before A/D overload. (as well as transients as most audio has ~18dB crest factors).

FWIW,
You actually have more output level with SQ6 (+22dBu) than with a MR18 (+21dBu) [albeit, these are negligible differences]
More dynamic range SQ6 (112dB) vs MR18 (107dB) [analogue to analogue]
More input max level (+30dBu) vs (+23.5dBu)
Lower distortion [THD+N] (0.002% unity) [0.003% @ half gain] vs (0.005% unity)

https://media.music-group.com/media/PLM/data/docs/P0C8H/MR18_QSG_WW.pdf
https://www.allen-heath.com/media/SQ-6-Technical-Datasheet.pdf

[Jens-DroesslerParticipant]

So you would be feeling better, if the signal meters just show 10dB more so you automatically dial in the gain 10dB lower? This is digital, any “analog style” metering is just something someone made up. The reference point within the digital domain is completely based on what the developer had in mind. It comes down to what I said earlier: If it clips, reduce gain. If that somehow colides with your style of working, your style of working has a flaw.

[CoronosParticipant]

I experienced the same thing: https://community.allen-heath.com/forums/topic/sq-6-low-output-level

The upshot of it was just to run everything hotter. Since you’ve already got the board maxed out, you might need bigger amps.

[lightingman117Participant]

No just no. Why would you need larger amps to achieve the same SPL?

Since you’ve already got the board maxed out, you might need bigger amps.

This is a gain structure problem not a system/component problem.

[lightingman117Participant]

https://avixa.azureedge.net/portal/docs/default-source/default-document-library/your-guide-to-setting-system-gain.pdf?sfvrsn=f000f197_0

Gain Structure Made Easy

https://support.biamp.com/General/Audio/Gain_structure%3A_input_and_output_levels

https://www.ravepubs.com/wp-content/uploads/2013/10/InfoComm_Audio-Gain-Structure_20131014.pdf

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