Sound issues

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This topic contains 3 replies, has 3 voices, and was last updated by Profile photo of Mike C Mike C 1 month, 1 week ago.

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  • #109434
    Profile photo of ShyamM
    ShyamM
    Participant

    Hi community,

    After some help regarding an issue I had recently – I was providing the sound for an event last weekend, all was fine during set up however then suddenly my volume levels dropped on my sound across all speakers and then came back to normal after a while (an hour or so) however this was super stressful and a headache – I had to increase gains on everything to get sound out but was at its limit and distorting (was only using LR no monitors were needed).

    The signal levels on my QU16 were still appearing as normal and no difference to usual.

    Grateful for any thoughts if anyone has experience this or what the issue could be – I’m not sure where this may have occurred, system details below

    System: Active speakers
    Mixer: QU16
    Speakers: QSC K8.2
    Cabling: XLR (connection to speakers through L+R output from the mixer)

    TIA.

    #109437
    Profile photo of Mike C
    Mike C
    Participant

    By chance did you have headphones get a chance to listen to the level at the
    headphone output?

    When do you need to use the system again?

    If by chance it does it again move the outputs to a stereo aux out like mix 9-10, have that set up for post fade / post all, set all the send levels to unity and maybe even copy your main L R output EQ settings to the mix output. You could do that ahead of time
    to be ready.

    Also you could set the ALT OUT to main L R and connect to those outputs to run the system. You would need a couple 1/4 inch TRS to XLR adapters.

    Both would be a good test to see if it’s all outputs or just the main stereo outs.

    #109438
    Profile photo of Hoody
    Hoody
    Participant

    No Sound Guv’!
    Equipment

    1 x QU – 16
    4 x RCF 705_ASII Active Subs
    2 x JBL 812p Tops
    1 x RCF ART 715-A MK4 Active Speaker
    4 x LD 400W Monitors

    At a pub gig for Buster James Rock Band in 2021, at the end of the first set, the backing music started coming from the left channel only. As I had taken a toilet break, I only noticed this on my return with less than 5 mins left of the break before the start of the second set.

    No one else had noticed. First, I checked that the desk and sound source were fine. I then had a close look at the speakers; the power light was on and there was a feint sound from them. Then I started a left to right cable swap on the desk and still no sound! To top it all, the singer told me his monitors had stopped working. The bass and guitar monitors were fine these as the other mains were powered from a different
    source.Especially by the second set when alcohol has worked its magic. Unless, of course, you have an insecure band member who announces it on the mic!
    No one else had noticed. First, I checked that the desk and sound source were fine. I then had a close look at the speakers; the power light was on and there was a feint sound from them. Then I started a left to right cable swap on the desk and still no sound! To top it all, the singer told me his monitors had stopped working. The bass and guitar monitors were fine.

    I was then in a total fluster and panned everything left then boosted the channel. Being a pub the crowd they didn’t notice a thing (experience has taught me that unless the problem is ‘no sound at all’, the crowd very rarely notice.) Especially by the second set when alcohol has worked its magic. Unless, of course, you have an insecure band member who announces it on the mic!

    I thought maybe something has blown my speaker amps on that channel (they are powered JBL SRX812p Tops and RCF705-ASII subs). So, I plugged in a spare speaker I brought in and nothing! The power LED’s and Level LED’s on the speakers and monitors were very dim and with the gain at MAX you could hear a little sound from the top.

    Well… with sweat pouring, the band finished the set as we had plenty of power to spare. The crowd were pleased and the band, who are seasoned pros, carried on; although fold back was difficult.

    The keyboard player had his keys reset at the start of the second set because he had put his pedal plug into the wrong socket. During set-up, the drummer’s monitor – which has a momentary on/off switch – switched off on its own too.

    When I got home and scratched my head knowing it was a power problem of some sort, I checked every power cord first and no problems; then every speaker and no problems either.

    Many said I hadn’t used low-cut and had my speakers power off through clipping. Others said I had a mix desk problem and had accidentally switched something off (both of which I knew it couldn’t have been as it was just one side of the PA which dropped which drew its power from a separate mains socket to the other as was proved just by switching the L/R XLR’s over but the fault was still there!

    All I knew was that it was a power problem. Then I told my brother what had happened. He used to play in a well-known covers band at the time and he told me he had once had the same problem.
    When people went outside at the pub, called the Otter in Norwich, to smoke, they put the patio heaters on.
    This triggered the same fault with the band. He could see the smokers switching the Halogen Patio heaters on which had a 5-minute timer. So, sound came on briefly then disappeared again. He could see it happening and put two and two together!

    Yes, I remembered a very drunk pair of ladies going outside to smoke just before the start of the bands set break and they stayed there for the rest of the evening with the patio heaters on; which I don’t blame them for, as we live on the North Norfolk coast and the wind does blow here. So probably wiring installed by a mate of the pub causing the problem!

    That’s my story, a lesson learned, also, I know now to trust my judgment even if it did not help on the night. Thanks to all my friends and sound tech friends out there and finally I hope this never happens to you and if it does, you’ll remember this!

    Of course the band blamed the sound engineer which had I tested the power outlets and wiring before hand I might have spotted the spur of a spur of a spur. However, in my defence from 6pm arrival to leaving at 12.30am for £150.00 I didn’t think I was being paid to do that.

    #109532
    Profile photo of Mike C
    Mike C
    Participant

    Could have been a power voltage issue, in a club who knows what else is on the same circuit as the outlets you plug into.

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