Amp "pop"

[Axtman]

SWR amps seem to "pop" when you turn them on or off. I am concerned that I am damaging the speaker when it does that...plus it is annoying. Is there a capacitor that I can put across the On/Off rocker switch to prevent this annoying sound? Thanks.

[Enzo]

Nope.

Pops are normal. SOme amps have a speaker delay relay, but many do not. The power on thump can never be larger than the maximum power out of the amp. In other words the pop will not be louder than you could play. if the speaker handles your play, it will handle the pop.

It isn't from the switch. Well at turn off there could be some switch noise. But mostly youare hearing the filter caps charging.

[Rick Erickson]

It is normal for an amp to have surges until the power supply and coupling caps have charged and stabilized. Many SWR amps have a Speaker On/Off switch which acts as a Standby switch for powering up or down. Just make sure the Speaker switch is in the "Off" position before switching the Power switch. If your amp doesn't have the speaker switch then you will probably just have to live with the thump. You might be able to minimise it by turning down the Volume or Master Volume controls before switching the Power.

RE

[Enzo]

Or pull the speaker cable before flipping the switch, that would work.

[PeaveyBandit]

I recently had an issue like this. Much to my amazement replacing the first two preamp tubes ch1/ch2 which happen to be JJs ECC83s with the new mullard reissues. I noticed the pop I couldn't seem to fix was suddenly gone and the amp was behaving nicely. Has been since. Fingers are firmly crossed.

I think my progress was made when I began pulling preamp tubes to see when the popping on/off issue would stop. That lead me to swapping the tubes for the hell of it. Shazam! Could have knocked me over with a feather. BFDR.

PB

[Enzo]

That could be from a number of things, interesting report. The SWR is a solid state amp though.

[ajeffcote]

My Fender DRRI pops when I turn the standby switch off.So I just turn the power off first.But I thought that should happen when powering up, not down.