"Scott McDonnell" bravely wrote to "All" (03 Feb 05 22:24:19)
--- on the heady topic of " Clicks/pops in 70V commercial audio system"

SM From: "Scott McDonnell"
SM Xref: aeinews sci.electronics.repair:9366

SM Georges,
SM Thanks for the reply!

SM I believe they are random. They are normally quite far between,
SM but are very loud and annoying. It's more like a "pop" though,
SM but with a very short crackle sound after the pop. At first it
SM seemed as though the bass was too high because it seems to
SM occur when a high-energy sound is present, though I hear it
SM on rare occassions during lower energy periods. I suspected
SM a capacitor drying up in the PA amp, but haven't had a chance
SM to open it up yet. I am not even sure how a 70V PA Amp
SM works.

SM There are many noise sources, but those sources have
SM always been there and this problem only recently started to
SM occur. I suppose it's possible something has a failing motor
SM in it that could be casuing the noise, but it seems unlikely.

SM I am planning to buy a new PA amp from Ebay, since I
SM found a comparable one for ~$20.

SM Here's some other ideas I had thought to try:

SM Using a choke coil to kill the sudden change in current,
SM but this seems like a jury-rigging solution.

SM A power conditioner? An expensive solution, but would
SM be neccessary if it is caused by inductive loads on the
SM same circuit. I am not 100% sure about this, but I
SM believe it is standard practice to place large appliances
SM like those used in the resturaunt on seperate circuits.


Scott, I know some amps are very sensitive to fluorescent lights being
turned on (or off). Especially if they are run with a lot of gain that
is being unused. For example if the volume is turned way up to
compensate for a weak source. The lighting circuit wire path makes a
difference. You might try experimenting with removing the equipement
to a different location/circuit, etc. Play with the light switches to
find if one of them is responsible. Maybe try a line filter for the
amp and receiver. Borrow a power conditioner as last resort indeed.

A*s*i*m*o*v

.... Isn't Fourier and it's applications a bitch!