Allen & Heath CQ desks

[Chienmortbb]

On 18/01/2026 at 20:30, Woodinblack said:

 

Like if you have a number of cables running together, he found that having a power cable and an audio cable running next to each other. But that seems not that likely

Audio cables and mains cables running side by side are deemed a bad idea the can cross each other at an angle, but it does effectively mean you have a long aerial from a transmitter running in close proximity to the receiving aerial of the audio input. 

 

There are a few cables that run a balanced cable and a mains cable in the same bundle, Andertons do one, but I cannot find the link. Sommer also do one,

Sommer DMX/Power or Audio and Power Cable. I may get some of the Sommer one to try but at almost €14 per metre excluding VAT, Duties and shipping costs....

[Phil Starr]

That's a very strange noise. I don't think it is a cable. It's not clear from the pic what inputs you have to the mixer. The Zoom seems to be on, was that connected to anything? I've had strange noises (nothing like that though) from my Zoom when the batteries are flat. It sounds to me like something entirely separate from your sound system something mechanical like a relay chattering, maybe on a freezer/washing machine or anything really. It could even be in  a neighbours house. That interfeence can either feed into your system from the mains or by radio waves. 

 

Anyway the first thing to do would be to disconnect everything from the mixer when you aren't using it and see if it ever makes the noise with everything disconnected. If it is fine at least you will be reassured it's your house and won't happen at a gig. Then reintroduce one thing at a time to see if any one connection causes the noise. If it recurs then check if it is that source which is faulty or the lead by swapping for a different lead with the same source. Good luck, these intermittent faults are often really hard to track down

[Chienmortbb]

Wise words @Phil Starr. I have seen similar reports on various CQ forums. However these are likely to be from the same person. I can only add to be methodical. For example, the Zoom may or may not be part of the problem and if removing that solve the problem, do not jump to conclusions. Neither box may be at fault, just the two together and/or cable combinations. 
 

Good luck with your detective work. 

[warwickhunt]

Not the same noise but we had a proper b4llache dealing with a pulsing 'noise' through our desk.  We thought we pinned it down to the sax players Zoom effects unit (when disconnected)... only to find that if he was plugged in and one of the guitar Helix was unplugged it went off!  Argh.