Problem With Spikes/Pops through Speakers

Archived from groups: rec.audio.tech (More info?)

I've heard of devices such as noise filters, AC Line interference filters
and spike suppressors, but am not sure if any of these or other devices can
solve my problem.

I have a mobile DJ setup consisting of a mixer, CD player, amp, Furman Power
Conditioner and light controller in a case.

I also have a laptop, external hard drive, subwoofer, cordless mic and fog
machine.

The mixer, CD player, cordless microphone, external hard drive, light
controller and laptop are all plugged into the Furman. The ground for the
laptop is lifted with a 3 to 2 prong adaptor which eliminates a previous
ground loop isolation problem that used to exist (i.e humming).

The Furman and amp are plugged into the same extension cord with a 3-socket
adaptor and plugged into the wall. The subwoofer is plugged into the wall
with its separate extension cord. The fog machine is also plugged into the
wall with its own extension cord.

Supposedly, each wall socket that each extension cord was plugged into was
on a separate circuit. However, whenever I pressed the fog machine switch
and released it, I would hear a loud "POP" going through the speakers. As a
result, I could not use the fog machine with the risk that the sound would
blow the speakers.

If the fog machine was actually on the same circuit as the amp or subwoofer,
I assume that would explain the popping sound? If they were not on the same
circuit, but each wall socket had the same ground source, could that explain
this?

In either event, since I often cannot control how I plug in my equipment at
a location, is there any device that will actually decrease or eliminate the
popping sound (i.e. something that I can plug the fog machine into)?

Thank you.

Andy

Archived from groups: rec.audio.tech (More info?)

Robert:

Thanks for your response.

I am not an electrician, so how do I do this? Opening up the fog machine,
and then what am I looking for?

The switch is actually a remote device that is plugged into the fog machine
with a 25 ft. long cord.


"Robert Gault" <robert.gault@worldnet.att.net> wrote in message
news:yU6lc.11035$Ut1.335428@bgtnsc05-news.ops.worldnet.att.net...
> Legaldeejay wrote:
>
> ><snip>
> > Supposedly, each wall socket that each extension cord was plugged into
was
> > on a separate circuit. However, whenever I pressed the fog machine
switch
> > and released it, I would hear a loud "POP" going through the speakers.
As a
> > result, I could not use the fog machine with the risk that the sound
would
> > blow the speakers.
> >
> > If the fog machine was actually on the same circuit as the amp or
subwoofer,
> > I assume that would explain the popping sound? If they were not on the
same
> > circuit, but each wall socket had the same ground source, could that
explain
> > this?
> >
> ><snip>
>
> If you have used this equipment before without pops, then the location
> wiring may be a problem. If you always have pops, then the fog machine
> may be generating RF or line spikes to which the amplification equipment
> is sensitive.
>
> The first thing to try would be to check the power switch for the fog
> machine. If it does not already have capacitors across the contacts,
> install a cap for each switch contact. That will prevent "arcing" which
> is a typical source for this type of noise problem.
>