How to get rid of popping noise?

[existingbrain]

Hello forum experts! Another day, another audio issue, so hoping to solicit your expertise here. The issue I'm having is that I hear a brief "popping" noise whenever I do one of the following:

• hit the mute button
• change input sources, for example switching from CD to USB input
• power off the system by turning the pre-amp off when connected to the power amp with 12V mono trigger
• starting or changing tracks in Roon

The popping is not terribly loud, but I'd like to get rid of it if at all possible. In order to get a quick and dirty measurement, I used an iPad and one of those decibel meter apps and observed about a 25db spike with the iPad right next to the tweeter. I've been assured by at least one expert on this forum that brief popping noises shouldn't damage the tweeters as long as it's not too loud. But "not too loud" is a bit subjective (maybe my hearing is crap), so it still unnerves me a bit every time I hear it.

For context, my audio chain consists of the following. I have two input sources (CD player and RPi4 used as Roon end-point) connected to a Yamaha RN800A integrated, which is used as a pre-amp and input selector. I have a separate power amp, Teac AP701, which is connected to the Yamaha's pre-out with RCA-to-XLR cables (Yamaha only has RCA pre-out). The Yamaha and Teac are also connected via 12V mono trigger cable. Finally, my speakers are connected to the Teac power amp with monoprice 12 guage speaker wires.

Here are a few things I've tried:

• I can avoid the power-off pop if I remove the trigger cable and turn off the Teac first, but all the other pops persist (e.g., change inputs, hit the mute button) even without a trigger connected.
• I saw some threads that showed pops could result from changing tracks in Roon that switches up the sampling rate, so I tried adjusting some of the Roon settings as well as a work-around mentioned by @staticV3 (applying a 'fake' PEQ filter) but none of this seemed to affect the popping behavior.
• No popping occurs whatsoever in any of the aforementioned circumstances when I take the Teac power amp out of the chain and hook the speakers up directly to the Yamaha integrated amp. This suggests it's either the Teac or some interaction between the two components is at fault, but I don't know how to further isolate the cause.
• I haven't tried this yet, but Yamaha support recommended that I try a "cheater plug" for the Teac. Will report back on how this works, but not sure if this is a viable long term solution given the risk of using cheater plugs.

Notably, the popping happens most reliably when I hit the mute button—it happens every time I hit mute and regardless of which source I'm in, CD player, RPi4/Roon. I've read elsewhere that this has to do with the voltage suddenly being cut off to the speakers, but not sure if this is what is going on with my system and how to remedy this if in fact this is the cause. Thanks to all in advance!

 

[Doodski]

No popping occurs whatsoever in any of the aforementioned circumstance when I take the Teac power amp out of the chain and hook the speakers up directly to the Yamaha integrated amp. This suggests it's either the Teac or some interaction between the two components is at fault, but I don't know how to further isolate the cause.

Notably, the popping happens most reliably is when I hit the mute button—it happens every time I hit mute and regardless of which source I'm in, CD player, RPi4/Roon. I've read elsewhere that this has to do with the voltage suddenly being cut off, but not sure if this is what is going on with my system and how to remedy this if in fact this is the cause. Thanks to all in advance!

It appears the mute circuitry (FETs or super beta BJT) in the Yamaha has a bit of bleed through as it is engaged. This is not a lone issue as I have seen it many times before. That's my guess on the issue.

 

[kemmler3D]

I've read elsewhere that this has to do with the voltage suddenly being cut off to the speakers, but not sure if this is what is going on with my system and how to remedy this if in fact this is the cause.

This is probably it.

A pop is nothing more than a straight line up or down in the waveform (voltage) which is fed to the speakers.

If there is any abrupt cutoff/on that makes it to the speakers, you're going to hear a pop.

Usually not much you can do about it without swapping out gear. Some is designed to have a smooth on/off.

However, if there's DC offset somewhere in your signal chain, it could make pops worse... not sure how that would creep in but it's possible messing with power/grounding might help? (out of my depth there but others here know a lot more).

However, you shouldn't worry about the pops unless they're really noticeably LOUD. A speaker is designed to handle whatever voltage input you throw at it, as long as it's not too much voltage - including clicks and pops.

 

[existingbrain]

It appears the mute circuitry (FETs or super beta BJT) in the Yamaha has a bit of bleed through as it is engaged. This is not a lone issue as I have seen it many times before. That's my guess on the issue.

Interesting, this seems to indicate a design flaw, or maybe Yamaha didn't think many people would use an integrated amp at this price point with an external power amp, so it's something they glossed over. In the cases you've seen before, has any resulting popping behavior ever led to speaker damage?

 

[existingbrain]

Usually not much you can do about it without swapping out gear. Some is designed to have a smooth on/off.

Here, the culprit would be the Yamaha pre-amp section, so that's the thing that I would swap out, correct?

However, if there's DC offset somewhere in your signal chain, it could make pops worse... not sure how that would creep in but it's possible messing with power/grounding might help? (out of my depth there but others here know a lot more).

Not sure what a DC offset is, so I'll have to look this up. Maybe this is the kind of thing that the 'cheater plug' is meant to address when the Yamaha tech recommended it?

However, you shouldn't worry about the pops unless they're really noticeably LOUD. A speaker is designed to handle whatever voltage input you throw at it, as long as it's not too much voltage - including clicks and pops.

Thanks, this is good to know! At the end of the day, the pops are annoying given how frequent they are, but I can deal with it as long as it doesn't damage my speakers.

 

[Doodski]

Interesting, this seems to indicate a design flaw, or maybe Yamaha didn't think many people would use an integrated amp at this price point with an external power amp, so it's something they glossed over. In the cases you've seen before, has any resulting popping behavior ever led to speaker damage?

I popped a couple of KEF 107.2 Reference Series tweeters with a high voltage static pop. That was a extreme pop/snap sound. I have also replaced many mute transistors that where leaky or entirely failed to mute. The mute operation never caused a tweeter or woofer mishap that I am aware of.

 

[Doodski]

Not sure what a DC offset is, so I'll have to look this up. Maybe this is the thing that the 'cheater plug' is meant to address when the Yamaha tech recommended it?

DC offset is when DC voltage and current is present at the amplifier speaker terminals with no signal present and when the amp is quiescent (Resting at a neutral state.) The DC offset causes the speaker drivers to either move out a little or move in a little depending if the DC offset is a positive voltage potential or a negative voltage potential. The speaker driver will stay at the position it is at with the DC offset and interfere with the normal operation of a speaker and amplifier interaction.

 

[existingbrain]

I popped a couple of KEF 107.2 reference Series tweeters with a high voltage static pop. That was a extreme pop/snap sound. I have also replaced many mute transistors that where leaky or entirely failed to mute. The mute operation never caused a tweeter or woofer mishap that I am aware of.

Just curious, in the case of your KEFs, what was the cause of the 'high voltage static pop'?

And side question, if there is some damage to a tweeter, would it obviously audible/noticeable? My assumption is that tweeter damage can happen gradually? And is not always binary, i.e, blown vs. not blown?

 

[existingbrain]

DC offset is when DC voltage and current is present at the amplifier speaker terminals with no signal present and when the amp is quiescent (Resting at a neutral state.) The DC offset causes the speaker drivers to either move out a little or move in a little depending if the DC offset is a positive voltage potential or a negative voltage potential. The speaker driver will stay at the position it is at with the DC offset and interfere with the normal operation of a speaker and amplifier interaction.

Thanks for the explanation. Based on this, I don't expect the cheater plug to do anything!

 

[kemmler3D]

if there is some damage to a tweeter, would it obviously audible/noticeable?

Generally a damaged tweeter results in a dramatic and sudden loss of treble, or various types of unwanted noises coming from the tweeter.

 

[Doodski]

Just curious, in the case of your KEFs, what was the cause of the 'high voltage static pop'?

I was walking around on my hardwood floor and sitting on my sofa and then I got up and was admiring my tri-amp'd home audio system and I touched a fat MIT RCA cable going into the midrange amp front panel and SNAP the static electricity powered the tweeter amp input and fried my tweeters with a loud SNAP sound! I have no idea how the static electricity made the tweeter amp fry the tweeter when I touched the midrange amp RCA cable but I have training in electrostatic discharge and preventative operations so I imagine all sorts of wild physics going on there when the tweeter fried.

And side question, if there is some damage to a tweeter, would it obviously audible/noticeable? My assumption is that tweeter damage can happen gradually? And is not always binary, i.e, blown vs. not blown?

There are different kinds of damage that tweeters succumb to as follows. Here are some of the main issues that can occur.>

-Overheating the voice coils and causing the adhesive to break down and the coils/windings of copper or aluminum wire to become loose in the voice coil gap and then a rattling and intermittent sound occurs.

-Clipping the amplifier power output causing a high DC voltage and DC current to be sent to the speakers. The DC voltage and DC current overheats the voice coils supremely and burns it black and to carbon.

-Intermittent connections on the voice coil braid wire lead occurs due to over-excursion of the driver travel. This is rare but I have fixed this fault many many times by repairing the braided lead.

- Spikes of power like I had occur with a high voltage static discharge into the audio system that can damage any of the drivers dependent on what circuit path the electrostatic discharge follows.

 

[Doodski]

Thanks for the explanation. Based on this, I don't expect the cheater plug to do anything!

I don't expect any change using it.

 

[kemmler3D]

DC offset is when DC voltage and current is present at the amplifier speaker terminals with no signal present and when the amp is quiescent (Resting at a neutral state.) The DC offset causes the speaker drivers to either move out a little or move in a little depending if the DC offset is a positive voltage potential or a negative voltage potential. The speaker driver will stay at the position it is at with the DC offset and interfere with the normal operation of a speaker and amplifier interaction.

@existingbrain just to clarify, there can be DC offset anywhere in the chain, even on a recording, but if you are hearing an extra-loud pop due to DC offset it would have to be present at the speaker also as Doodski mentioned.

 

[existingbrain]

I was walking around on my hardwood floor and sitting on my sofa and then I got up and was admiring my tri-amp'd home audio system and I touched a fat MIT RCA cable going into the midrange amp front panel and SNAP the static electricity powered the tweeter amp input and fried my tweeters with a loud SNAP sound! I have no idea how the static electricity made the tweeter amp fry the tweeter when I touched the midrange amp RCA cable but I have training in electrostatic discharge and preventative operations so I imagine all sorts of wild physics going on there when the tweeter fried.

That's a WILD story! Thanks for sharing. Incidentally, I get static discharge 9 out of 10 times I get up from my couch and shuffle my feet on hardwood 9 feet over to the rack to swap out a CD, so now I'm thinking great, yet another way I'll potentially damage my speakers

There are different kinds of damage that tweeters succumb to as follows. Here are some of the main issues that can occur.>

-Overheating the voice coils and causing the adhesive to break down and the coils/windings of copper or aluminum wire to become loose in the voice coil gap and then a rattling and intermittent sound occurs.

-Clipping the amplifier power output causing a high DC voltage and DC current to be sent to the speakers. The DC voltage and DC current overheats the voice coils supremely and burns it black and to carbon.

-Intermittent connections on the voice coil braid wire lead occurs due to over-excursion of the driver travel. This is rare but I have fixed this fault many many times by repairing the braided lead.

- Spikes of power like I had occur with a high voltage static discharge into the audio system that can damage any of the drivers dependent on what circuit path the electrostatic discharge follows.

Got it, so if I understand correctly, there are types of damage that leads to "intermittent sound" which would be audible in music (or possibly a test tone sweep) without disrupting the entire treble range.

 

[Doodski]

Got it, so if I understand correctly, there are types of damage that leads to "intermittent sound" which would be audible in music (or possibly a test tone sweep) without disrupting the entire treble range.

Yes, damages often lead to scratchy and crackly intermittent sound and rattling of the voice coil metal against the speaker motor assembly. If you want to check your speakers then frequency sweep the speakers using this software I link you to. Start low frequency and adjust the volume as you slowly sweep the frequency to the upper 15 kiloHertz and up to 20kHz which you probably can't even hear but that how a sweep is done. Listen for abnormalities in the sine wave sound. Look for rattles in the cabinet, rattles in the woofer, noises in the midrange if you have them and of course carefully sweep the tweeters at not a loud level because you could damage them so use something comfortable for your ears but not deafening loud.

Online Tone Generator - generate pure tones of any frequency

szynalski.com