Amplifier static click/pop through speaker when turning on & off
Clipdat
Posts: 7,961
Calling all electronics engineers and amplifier experts!
What would cause an amplifier that was previously silent when turning on & off, to randomly start making a static click/pop through the speaker when turning it on and off?
I realize different amplifiers tend to make various sounds upon powering up and down, but I'm specifically curious about what would cause this behavior to suddenly start happening out of the blue.
It's not an outrageously loud static click/pop sound, so I don't think it'll damage anything, but this just started happening to me so I'm curious. By the way these are monoblocks, and the other one is still silent, no static click/pops upon power up or down.
What would cause an amplifier that was previously silent when turning on & off, to randomly start making a static click/pop through the speaker when turning it on and off?
I realize different amplifiers tend to make various sounds upon powering up and down, but I'm specifically curious about what would cause this behavior to suddenly start happening out of the blue.
It's not an outrageously loud static click/pop sound, so I don't think it'll damage anything, but this just started happening to me so I'm curious. By the way these are monoblocks, and the other one is still silent, no static click/pops upon power up or down.
Comments
However, it's worth testing that theory.
Second step switch speaker outputs on current preamp see if it follows or you can do it first. Just process of elimination
I'm out off to bed good luck
Other; S60'S, M10 series II, M7C's, Hafler XL600 amp, RB-980BX, Parasound HCA-1500 amp , P5 preamp, all in storage. All vintage Polk have had crossover rebuilds and tweeter upgrades.
There are three things that give a man a false sense of courage, a keyboard, alcohol and a firearm.
Motorhead, 4.12.20
tonyb said " but even socialists can do a good thing here and there
Social media makes dumb people dumber and smart people dumb and dumber.
lol! I knew this was coming.
I told my wife last night "If I ask on the forum about this, they're just going to say I should have been keeping them on all the time."
If you have a source with its own attenuator, bypass the preamp entirely and see what happens. Heck, if you want, you can disconnect everything from the input of the power amplifier, turn it (the power amp) on - let it come up to operating 'speed' - then turn it off and see if it clicks/pops/whirrs/whatever.
DC offset from the new preamp is certainly a possibility - direct coupled circuitry can be anywhere from annoying to dangerous when there's any DC offset anywhere in a signal train.
If there's a constant DC offset from the preamp, it should be measurable with a DMM (if one is curious/motivated) enough.
If not related to the "new" preamp -- Clicks and noises on turn on and shut off in an amplifier, if they "suddenly" occur, are often symptomatic of a failing capacitor.
Remember that things get very nonlinear in a power supply when current is first applied (before caps charge up and the system settles into steady state operation) and at shut down. This is one of the reasons (besides "acoustic aesthetics") that many components have relays that, in essence, disconnect the loudspeakers until the power supply is stabilized.
I'll unplug the RCA cable going to it and then try powering it on/off that way and see if it still makes the static noise. Good idea!
Wasn't it Julius Caesar who said that (albeit in Latin or Italian or Greek or suchlike furrin' language)?
EDIT: Wiki-p sez it was Philip II of Macedon. Whatev's
I guess these don't like to be turned on with no cable attached?
I had the preamp set to input 1 and I turned on the source (cd player) that's connected to input 3 and there was a loud static pop through both speakers. Volume knob was also all the way down. What the hell.
Shorted inputs would be better (as stated earlier) but any properly designed and functioning amplifier should be OK with no inputs.
I have everything playing now and it sounds fine, so crisis averted I guess.
I still don't know why turning on a component hooked up to a completely separate input with the volume knob all the way down would make a loud static click through the speakers.
I guess both the pre and the amps are an extremely minimalist design that is more susceptible to this type of thing?
Other; S60'S, M10 series II, M7C's, Hafler XL600 amp, RB-980BX, Parasound HCA-1500 amp , P5 preamp, all in storage. All vintage Polk have had crossover rebuilds and tweeter upgrades.
There are three things that give a man a false sense of courage, a keyboard, alcohol and a firearm.
Motorhead, 4.12.20
tonyb said " but even socialists can do a good thing here and there
Social media makes dumb people dumber and smart people dumb and dumber.
The thump represents transient power supply instability, and is normal -- although many (solid state) amplifiers use a relay to keep the 'warm up' sounds from being passed along to loudspeakers.
Buzzing is typically indicative of an ungrounded condition (or possibly a ground loop -- although ground loop hum is usually fairly quiet). The other possibility, of course, is failing power supply filter capacitors, but the symptoms sound like the first or second explanation is most likely. I guess it is possible that the feedback loop in the amp requires a grounded input, and thus goes nuts when open-circuited. You can always turn the amp on with whatever it is hooked to turned off (but still connected and plugged in/grounded) and see how the amp reacts.
Dead silence on turn on can only be guaranteed with a relay that disconnects the speakers from the power amp outputs until the system's stable, AFAIK.
I was finished so I turned the volume knob on the preamp all the way down, and then stopped the record and took it off the turntable and switched off the table. I was 4 feet away putting the record back into it's sleeve and randomly there was a static pop heard through the speakers. Bizarre, as I wasn't near the system and the volume knob was all the way down.
Then when I switched off the amps I switched off the left one first that's previously had no turn on/off noises and it made a static pop. And then the right one made one upon power off as well.
Not sure what's going on with my system but there's definitely some static popping oddities going on and it's slightly annoying.
Left amp powered on first completely silently. No static click, literally silent.
Right amp powered on with a moderately loud static click heard through the right speaker.
In terms of the actual performance, everything still sounds absolutely fantastic. There doesn't seem to be any degradation to their performance, or their ability to draw me into the music and strongly hold my attention while taking me on an emotional ride of lush, involving sound.
I will switch to vinyl later and back to CD and see if there's any more random static popping or anything strange.
It was difficult to discern if it came from both speakers, but if I had to guess I'd say it came from the right speaker.
I think something is definitely going on with one or both amps.
Does Verty Audio know of any problems arising with these amps happening across the line of mono blocks?