Help - Small "popping" sound from Speakers

[PAPPA3]

Hi guys, I'm experiencing a feint 'popping' sound from my amp when switching between sources.  It's only on the one channel (RHS), and causes the speaker to emit a feint 'pop' everytime I switch between sources.  I've changed sources, changed speaker cables and changed speakers, to eliminate all other possibilities, but it's still there on the same side.  I've restored all factory default settings and that hasn't helped.

Any ideas as to what the cause could be or what I could try?  The amp is virtually new.

[Headsh0t]

A small "pop or thud" is quite normal as far as i know, especially if your not turning down the volume before switching inputs. Is there you could mute it before changing and then un-mute? I Highly doubt your cables are to blame as they are on the output, you're switching input, so any changes seen before the amplifier board is simply amp'd up. Which then get heard. I have read online that some amps really don't like their inputs switched around while they are doing there thing.

// When you hear the noise, is there visible speaker cone movement, is this a tube amp, solid state, pre-amp...?

[PAPPA3]

It's a normal av amp. 

It's just on the one channel, not on both. 

There is visible movement of the woofer.  The sound occurs when switching volume to mute.  Then when it's muted while switching sources, there's not 'popping'.

[Byrd]

Hi guys, I'm experiencing a feint 'popping' sound from my amp when switching between sources.

You are going a bit off topic in your first post there Pappa. Are you discussing a sound comming from your amp or is the sound comming from your speakers?

Just kidding

Try disconnecting all of your sources and then switching sources on the amp and see if it does the same thing.

[windshear]

It sounds like a digital/muting issue. Most receivers mute the output while changing source inputs then reengages it once the DSP's have locked onto the signal. Sometimes the unmuting is too quick depending on the method of implementation. The other source of the pop could be in the volume stage where a digital controlled attenuator does a similar thing in terms of muting the sound. One way to confirm where the problem is  to try it with either a digital signal or an analogue signal. When using an analogue signal force the source to use analogue only and not use an auto format selection mode. This should show where the problem is. Once you have found it ...... there is not much you can do      A lot of the receivers/processors do this, the world is not perfect. Most people dont even hear this or get used to it and forget. Audiophiles dont 

[Hi-Phibian]

Odd that it is one channel though. Makes ne have doubts about being normal.

[Hi-Phibian]

as asked by another poster, what happens when no sources at all are connected?

[Ampdog]

From another Pappa,

In the first post you mentioned changing sources. Do also try change the same source's inputs left/right around. If no difference the problem is not with the source. After that .... the visible movement on the woofer indicates that there is dc switching coming from somewhere. Where?  ... no idea unless one can properly check the input circuits of the amplifier. A circuit diagram plus instruments and some expertise would be required for that.

[PAPPA3]

Someone else also said it's a DC problem.  He says it's not a problem, unless the woofer pulls back and stays there a while before releasing.  I trust this analysis is correct.  He seems to know his stuff.

I'm not keen to send the amp in for checking if this is a common 'problem'.  The woofer movement is visible when the popping happens, but the woofer doesn't remain recessed for long.  I did a YPAO check (it's a Yamaha amp), and one result was 'WIRING'.  I'm guessing this means speaker wire.  Other than that there is no problem, and the amp and speakers work very well.

[Hi-Phibian]

It is a problem if it is there and it should not be despite what 2nd level of protection there may be. Good engineering is dc blocking on in and outputs, that does not make one of the two obsolete which is what your other source seems to be suggesting.

[GearSlave]

He says it's not a problem, unless the woofer pulls back and stays there a while before releasing.

That's not entirely correct. There might be a DC component fed through a capacitor that gets charged up over time, thus only blocking DC then. But make no mistake, DC will cause the above symptom, even if the woofer returns to it's normal position after a cap in the signal path is charged.

[Hi-Phibian]

What I was trying to say.. Source = Person

[PAPPA3]

I'm growing accustomed to the sound.  I always mute or reduce volume when changing sources, etc.  That makes the sound less audible (and irritating).

The long and short of my original question is: should I be worried? will the problem increase? is it quite common - which means it's a bit of a nuisance, but no cause for alarm?