Bursts of static/white noise

[Timewarp]

After nearly 40 years of DJing, i thought i had come across everything but what happened the other night shook me as i don't what is happening. Playing along nicely and then suddenly had a long burst of what i can only describe as very loud static or white noise pouring through the speakers. i immediately shut down and started up again and within another 30 minutes it happened again and after shutting down and starting again it happened again after about 20 mins. I changed plug sockets, took my radio mic off and replaced it with a lead mic and for the last hour it was fine, but i cant have this again. Has anyone had any similar experiences?

I am wondering if its a lead issue, but which one? Is it the radio Mic? . Any suggestions?

Regards

Rob

[Excalibur]

After nearly 40 years of DJing, i thought i had come across everything but what happened the other night shook me as i don't what is happening. Playing along nicely and then suddenly had a long burst of what i can only describe as very loud static or white noise pouring through the speakers. i immediately shut down and started up again and within another 30 minutes it happened again and after shutting down and starting again it happened again after about 20 mins. I changed plug sockets, took my radio mic off and replaced it with a lead mic and for the last hour it was fine, but i cant have this again. Has anyone had any similar experiences?

I am wondering if its a lead issue, but which one? Is it the radio Mic? . Any suggestions?

Regards

Rob

Hello Rob. First, let me put my Mod's hat on, and ask you to introduce yourself in the Newbies section, cos we're a a nosey lot, and like to know who we're typing to.

Second, as a DJ who has been around a bit, I have experienced similar issues. Usually, it has been attributed to things like fridges cutting in, and squirting bursts of noise into the system exactly as you describe. I'm not a sparky, so can't tell you much more, and can't offer solutions, sorry. Tends to be venue specific, in my opinion.

[rth_discos]

If the radio mic was "live" (that is, the receiver, rather than the microphone itself), unless your mic is on a licensed channel (which has low risk of interference), then there's every chance you experiences co-channel interference from another device.

I've come across this once when working at a venue that was close to a very small local airport. But any number of devices can cause this. If it doesn't happen at your next gig, then it could be something that was specific to that venue. Even changing the channel of your radio mic can be enough to fix it if it does happen again.

[Imagine]

Funny enough I had this today as well.

A village hall I've never worked in before so not entirely sure what's there (apart from WiFi, fridges in the kitchen, air con and all sorts of other electronics as they let it out for things like business meetings). My headset mic kept going berserk for some reason. I had to take to controlling the on-off from the Prime instead of the mic itself which cured the problem but a pain in the wossits when you're at a kids party and "out front" for most of it.

[Excalibur]

Gavin and Wayne bring up the possibility of other communication equipment being the cause. I know in the past we've had reports of previously faultless kit throwing a wobbler only in certain areas, eg airports, naval bases, or similar.

The old VHF kits could pick up all sorts of things, apparently sometimes taxi drivers and the like. I had to bin a beloved Shure radio mic because it was on a Portugese or Spanish frequency, and became totally unusable, because of interference. I presume that yours is a Channel 70, 863-865? The channel 38, down in 606-614 are much less prone to issues. We haven't asked if your radio mic is digital, 2.4GHz type. That can be mighty crowded in some places.

To be honest, I think we're looking for a needle in a haystack, but we may get lucky.

[Imagine]

The old VHF kits could pick up all sorts of things, apparently sometimes taxi drivers and the like.


Reminds me of a NYE gig I did many years ago where the kitchen communicated with the bar staff about orders ready to be taken out via some sort of microphone/speaker system. Spent most of the night wondering how the food orders were managing to come out over my PA :daft:

[Timewarp]

Reminds me of a NYE gig I did many years ago where the kitchen communicated with the bar staff about orders ready to be taken out via some sort of microphone/speaker system. Spent most of the night wondering how the food orders were managing to come out over my PA :daft:

Thanks everyone for your replies.

I'm not having bar staff orders or taxi interference, though i have had that in the past. These are definitely bursts of static that don't stop until the volume is turned off or i have shut down the speakers. I have done this venue once before without issues and as you say, i feel like its looking for a needle in a haystack. I'm borrowing a resistance meter and intend to check all my kettle leads and speaker cables. I run from a laptop these days, so i don't know if any of these static bursts are coming from that either.

Thanks for your help

[Excalibur]

Thanks everyone for your replies.

I'm not having bar staff orders or taxi interference, though i have had that in the past. These are definitely bursts of static that don't stop until the volume is turned off or i have shut down the speakers. I have done this venue once before without issues and as you say, i feel like its looking for a needle in a haystack. I'm borrowing a resistance meter and intend to check all my kettle leads and speaker cables. I run from a laptop these days, so i don't know if any of these static bursts are coming from that either.

Thanks for your help

The only thing I'd be 99% certain about would be that it's venue related. Usually a fridge/freezer/thermostat controlled item firing up intermittently. Not always, but very often.

[DJ Jules]

I'd almost put money on it being one of two things:

1. Radio mic - the receivers have a squelch mechanism that mutes the output when they lose the signal from the handset and this prevents static from coming through the output when the handset is turned off. If the signal is weak or something else is interfering with it then there can be enough signal for that mechanism not to kick in, but not enough to get a clear signal through. And then you get static hiss. This can also happen if there is someone else in the area (and it can be quite a large area) who is using a mic or other transmitter on the same frequency as your mic system. If it goes away when you mute the mic channel then that's your culprit. As others have said, some frequencies are more prone to this than others as some are open channels and others are regulated.

2. If you're using a controller and laptop/software then disconnects or a poor signal between the controller and the laptop can cause hiss (basically it can happen when the buffer runs out in the controller). This can also sometimes happen if the laptop is overloaded. Usually you'll see the track stutter on the laptop screen if this is the culprit.

Hope this helps a little?

Julian

[DeckstarDeluxe]

If it was me, I'd be setting it all up again and trying to re-create the problem. Problem solving is much easier when you're not giving yourself a heart attack about it. Take out one element one by one until you find the problem lead, socket etc...

[Timewarp]

Once again, thank you for your replies, they all makes sense. The only thing i will say is that it's not a hiss, its like a crackling static noise, very loud. I have borrowed a multimeter to check all my cables and i will not use the radio mic next time and see how it goes.

[Excalibur]

If it was me, I'd be setting it all up again and trying to re-create the problem. Problem solving is much easier when you're not giving yourself a heart attack about it. Take out one element one by one until you find the problem lead, socket etc...
Well yes, but:
If it's venue specific ( as I suspect it may well be ) you'll never find it at home.


Once again, thank you for your replies, they all makes sense. The only thing i will say is that it's not a hiss, its like a crackling static noise, very loud. I have borrowed a multimeter to check all my cables and i will not use the radio mic next time and see how it goes.

Now personally, I would. Granted, I would have a cabled mic wired in as well, and a second cabled mic on standby, in case it isdown to the radio mic.

I'm now about to wander off into my shed to recreate an intermittent DMX issue, which I feel confident will be conspicuous by its absence. :bang:

[mattydj50]

The only thing I'd be 99% certain about would be that it's venue related. Usually a fridge/freezer/thermostat controlled item firing up intermittently. Not always, but very often.

Many years ago, I had an old second hand VHF radio mic which was affected by some new electronic tills that had been installed in the bar, which backed on to where my set up was. Switched to a lead Mic there and Robert is your father's brother.