Right & Left Volumes Different on QU-16

[rgalv001]

I have noticed that the right and left volumes are not balanced on my Qu-16. One speaker volume side is always much louder on one side than the other for vocals and instruments. Is there fix for this? My amp on the mains are evenly processed and balanced. Issue seems to be RL left outputs from QU. I would hate to be panning each channel to the weaker side to compensate for this. Any help would be appreciated.

[Victor Kennedy]

Have you checked that the tweeters or such in your speakers are all working? Have you checked the Balance of channels on the QU?

I’m sure you have, but other than those things, if your power amp is ok, you may need to systematically re-check your whole signal path.

[rgalv001]

I will double check tweeters. However when I run a stereo iPad mix for music, it’s balanced and on a mono signal(vocals), volume balance becomes very noticeable. Never had to but what is process to check signal path. Previously ran 2 SRX7125 mains and noticed difference. Now run 2 Community SLS920’s and same issue. Thought at first it was SRX’s.

[JohnK]

Can we assume you have already switched the L & R cables coming out of the board to confirm that the problem is in the board and not downstream?

[MarkPAman]

…. and after you’ve done that, check that the balance control for L&R master strip is set in the centre.

Do the desk’s meters show the same level at the output?

[Mike C]

Do the cable swap test fist and let up know what happens. If the same speaker still has lower volume it’s going to be something between the mixer up to and including the speaker.

If the lower volume speaker changes to the other speaker that means it coming out of the mixer lower one main output channel. If that is the case it still could be a setting within the mixer causing the issue.

Are you using the main left right outputs on the mixer?
What do you do in between the mixer and your power amp, EQ, DSP ect?

[rgalv001]

I will be swapping cables later today when I do a test in my garage. I noticed the issue at an event I was providing sound for. I had noticed before thought maybe that was normal.
From the QU-16 outs, it goes into a BBE 882i to help with tweaking, then on to iTech amps with all the processing internally.
Mains – iTech4000 stereo to 2 Community SLS920’s
Aux Subs -iTech8000 Y output cable to Mix 10 – Running 4 EAW SB250’s. One side was punching/other side eh…
1. I will swap cables
2. I will bypass BBE
3. I will check settings in mixer
3. I will reset mixer
Thanks All! I will post outcome.

[MarkPAman]

So Subs are driven from different output(s) to the tops?

Test with just tops first:

If swapping the desk outputs leaves the same speaker quieter, then try swapping at the BBE outputs (rather than bypassing) to start with. This will narrow down the location of the problem. You could carry on down the chain by swapping amp output too if the fault stays with the same speaker.

Should the other speaker become quieter when you swap at the desk, then it’s time to do 3 & 4.

I’m not clear whether you’re running the subs mono from just output 10, or stereo from 9&10. If mono, then it can’t be a desk problem, if stereo, then test as for the tops.

[rgalv001]

Tops are separate RL. Subs are on Aux 10 only with Y cable from Amp Ch 1-2 into Mix 10. Will try Ch 1 into mix 10 and Ch 2 into mix 9.

[Mike C]

Let us know what your cable swapping test does.

Let me be the first in line to say that you REALLY need to dump the
BBE 882i.
You have a great board, amps and speakers, all the ingredients are
there to make great sound without the BBE.

[debzdoodle]

Agreed 100% – DITCH THE BBE POS. It has been proven many times to ruin sound and is completely unnecessary in a sound system. Regrdless of what you find to be a problem, spend your money on a good EQ instead. FWIW.. even the BBE bypass is not a true bypass so if you attempt to use it to compare sound quality, you will not get a true comparison.

[Mike C]

Between his amps and the mixer he really doesn’t need any more speaker processing

[rgalv001]

Got it. Disconnected it, just had to tweak EQ a bit. Sounds cleaner!
Checked all wires, all ok, switched them back and forth, switched channels on iTech. Still had a slight imbalance. Left appears to be louder?
Tomorrow I will reset mixer and check processing in iTech on both channels.
Thanks for all the advice.

[Mike C]

Do your cable swapping in an order that be tracked and verified as in don’t swap everything at once.

Start at the mixer swap the output cables and see if the lower speaker moves to the other side.

Swap the speaker cables at the amp output, see if the lower speaker moves to the other side.

Try using the internal pink noise generator as a level reference sent to the left right main outs. You could also send the pink noise to a stereo mix like 9&10 and then plug your cables feeding the amp into those outputs to see what you get.

Here’s an idea, take a XLR Y cable to feed both cables going to the amp and then you can send the same signal and level to both amp channels, if one speaker is lower you know it’s somewhere between the input cable to the amp and the speaker.

Good idea on checking the iTech processing, there’s a lot of processing stages in those amps!

[airickess]

Mix 9 & 10 are a stereo pair and cannot be separated, so you should choose another mono mix for your subs or run the subs in stereo, with Mix 9 the left and Mix 10 the right.
Make sure your iTech amp for the subs has the correct processor setting for the sub woofers (i.e. proper crossover/low-pass filter setting).

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