Stage power issues

rsvmark

Played a gig today at Coventry Motofest. Big shindig by the council, live music stage type thing.

The trouble started from the off. Set up the rig, and switched both amps on to get a level for the sound guys. 1 amp was absolutely normal while the other was flipping horrid and was picking up interference from somewhere. By process of elimination we traced it back to the stage power which didn’t like my mains power adapter so we unplugged both amps and went straight into stage power. Then we struggled with power to the pedal board so again, moved it to a different supply which lowered the noise.

Did the gig fine but had to lose the compressor which was much more hissy than normal. Even without the compressor there was a hissy, fizzy hum, and had to roll off the treble a little to compensate. Normally the rig is quiet between songs so never need to roll off the volume but I did today.

I can only conclude it was shitty power. The sound guys after told me everything was off a genny so just after some advice. Is there anything you can buy to isolate/regulate and improve the quality of power on stage?

maltingsaudio

Short of bringing your own genset no. The first thing you need to do is check your gear befor the show ensuring all mains cables and electrical equipment is up to snuff. If you gig regularly do this once a week, take all plugs apart and check all terminals are tight, plug gear into a known source and satisfy yourself everything is right.
When you get on stage don’t be afraid to check the sockets your plugging into by putting a mains tester into it and checking they are correct. It is not inconceivable that an earth may go astray on a supply if it’s been up for three or for days with loads of bands plugging in and unplugging every night. The stage crew should be on this but a extra check is always a good idea. Also plug in where you are told to, don’t just see a socket and plug into it, it could be the lights or the rigging circuit.

On the subject of your mains power adaptor I’m going to guess this was a four or six gang extension, the sockets on these, or more precisely the copper sockets you plug goes into inside the adaptor can wear and expand so the prongs on your plug don’t connect well and cause intermittent connection. Again a common fault down to mechanical wear which can be picked up if you check your gear regularly 

shufflebeat

maltingsaudio said:

When you get on stage don’t be afraid to check the sockets you’re plugging into by putting a mains tester into it and checking they are correct.

This is good advice.

Also, a bad FX power supply can be a significant weak link which will be passable on a good night but a few small issues will set it off badly.

Don’t forget to check your guitar leads, particularly solid earth connections.

rsvmark

Thanks both. While I don’t often run both amps at home, generally the hum is low, fx are fine (powered by voodoo labs 4x4) so thanks for the advice and I will buy a mains tester, something like this?

https://www.screwfix.com/p/lap-ms6860d-16a-socket-tester-230v-ac/91596?kpid=91596&ds_rl=1244066&gclid=Cj0KCQjw7PCjBhDwARIsANo7CgmPOl3vBYRJBcTCUJHM-bVDVVMep299ab7cNl5t1pJ1M95YK2Cbpr8aAsZhEALw_wcB&gclsrc=aw.ds

I do know my compressor is a bit hissy but by its very nature, they are all going to do that. I also wonder whether my guitar made it worse….. used my vintage strat so am guessing shielding etc wasn’t perfect back then. I’m guessing it was possibly a combination of all the above. To be fair the sound guy hadn’t seen it before so I am not going to beat myself up too much….. but learn to use the volume on the guitar and mute on the switcher!

digitalscream

This is precisely why I went with my DIY USB power bank approach for powering my pedalboard - far more reliable and only susceptible to power issues in the amp's supply (which is usually more robust anyway).

shufflebeat

That tester will do fine. It won’t tell you everything but it will point out a few potential no-nos.