Sign In:     

Forum: General Discussion

Topic: Inteference between smoke machine / soundcard ??? - Page: 1

This part of topic is old and might contain outdated or incorrect information

Hi,

I'm having an issue with some kind of inteference which is definately being caused by a venue smoke machine, but i'm not sure exactly why or what the smoke machine is intefering with.

The problem is intermittent and completely random. The effect is my laptop freezes (the VDJ deck stops turning) and a high pitched squelch type noise (like cd timecode) comes through the speakers.

This happens when pressing the button for the venues smoke machine. Sometimes it lasts for a few seconds after the button is released, occasionally it doesn't stop and reboot of the latop is required!

My equipment:

Dell XPS laptop 90w power supply.

RME RPM external soundcard which connects through ExpressCard and external IO box is powered by an external power supply.


I've tried running the laptop on battery power and the problem is still there. I'm not sure but I think the smoke machine may be interfering with the external sound card.

I'm hoping to find suggestions of what the cause is, the equipment thats being effected and possible cures.

As always, thanks in advance for any help offered!

Gary
 
Posted Tue 07 Dec 10 @ 2:23 pm
Sounds like your button is acting as a transmitter, and the sound card as a receiver. Did this just start, or has it been going on for some time? Is there carpet in the booth?
 
You have to use a different socket to plug your pa system into, it is common to get interference from smoke machines if plugged into the same ring main or worse still, extension lead.
 
There is carpet. Its always done it but got worse recently. The smoke machine is powered from the same ring main as the rest of the equipment and an extension lead is being used with it too. Its impossible for me to use a different ring main, what would you guys suggest?

Gary
 
Plug it into the wall socket from a standard 2m lead. Any one other than the one your pa's plugged into.
 
Ok, i'll give it a go. The smoke machine belongs to the venue and is mounted high up above my head. I don't think shortening the cable is an option, although I can try plugging it in somewhere else for starters and see if that helps.
 
Does it do this without the sound card? If it does, then I would say it's the mains. You can try one of these on the mixer. You can't run the smoke machine with an extension cord, to another outlet on a different breaker? Last but not least, spray the carpet with a little water. Static gets worse in the winter time because of the dry heat. I learned this the hard way.
 
happened to me aswell but since ive got spurius power lead and never plug lights or smoke machine into same board as dj equipment mixers players ect
 
Whats surprised me is the smoke machine hasn't been moved in over 2 years, my equipment hasn't changed either and its just become a recent thing. Before it might happen once every 2 or 3 months, now its happening all night every night. Its not my rig, just my laptop. Maybe someone at the venue has unplugged something and plugged it in somewhere else??
 
exactly mate.could be getting earth feedback from something
 
Or a frayed wire touching something. Again, spray the carpet and let me know what happens.
 
Have you checked the machine plug, lose terminals on them cause this too.
 
You're getting a ground loop feedback from the smoke machine since you plug your equipment in the same outlet ring operated by the same circuit breaker. All you have to do is invest in a power conditioner whether compact or rack-mount and a hum/buzz eliminator. I recommend Furman P-1800 PF (Compact) or PL-8 C (Rack mount) and ART DTI $50 or Rolls HE18 $52.Connect the hum eliminator between your mixer and amp or your DJ mixer and main mixer for maximum protection just in case the power conditioner doesn't suck up the entire hum.I guarantee your problem will be fixed if you follow my instructions.
 
In case that your budget is concerned I'll go ahead and include the price for each item and also submit a cheaper power conditioner...
Furman AC-215A $200 (Compact) or PL-8 C (Rack mount) $120 and ART DTI $50 or Rolls HE18 $52
Furman P-1800 PF $400 (Compact)................source: zzsounds.com or sweetwater.com

You're getting a ground loop feedback from the smoke machine since you plug your equipment in the same outlet ring operated by the same circuit breaker. All you have to do is invest in a power conditioner whether compact or rack-mount and a hum/buzz eliminator. I recommend Furman AC-215A $200 (Compact) or PL-8 C (Rack mount) $120 and ART DTI $50 or Rolls HE18 $52.Connect the hum eliminator between your mixer and amp or your DJ mixer and main mixer for maximum protection just in case the power conditioner doesn't suck up the entire hum.I guarantee your problem will be fixed if you follow my instructions.
 
I use a Samson powerstrip ps10 to connect my pa together however I don't know if it's a power conditioner?

looks like Fulman only serve the US, look and the inputs.
 
The Samson Powerstrip looks good, but more for installations or complete mobile rigs. I just take my laptop, external drives and soundcard to the venue and plug into thier system. Something a bit more mobile would be ideal as I already take a 6 gang trailing socket for radio mic and the above.
 
 
Correct me if i'm wrong, but aren't they just UPS's for power failures?
 
 
GaryBr wrote :
Correct me if i'm wrong, but aren't they just UPS's for power failures?


There is an added benefit though - device from a proper UPS are run from the batteries all the time (so no switchover delay - hence uninterruptable). The inverter in a decent UPS will produce a lovely clean sine wave, regardless of what else happens on the mains circuit (which only really charges the batteries).
 
80%