Stereo sound leaking to center channel.

[alitomr1979]

Hello all,

I am not sure this post belongs here. If it doesn’t I am sorry, moderators. Feel free to move the appropriate section.

I am hearing some distortion coming from the center channel and I think it is related to sound leaking from the mains to the center. My system is a Yamaha A2070 powering 4 height speakers and a pair of surrounds. The center is the preout of thw receiver to a Crown XLS1502, to the KEF R2C. The mains are the preouts connected to the Topping Pre90 preamp, and from the to the Peachtree Audio AMP500, which is powering KEF R3s.

The preamp XLR outs go the AMP500, and the RCA outs go to two SB2000 subwoofers.

I use Roon to listen to music. a Raspberry Pi4 is a stremer with a Gustard R26 and an SMSL M400. They both go the Pre90 preamp.

When listening to music I have noticed a very small amount of sound coming from the center channel. For the most part it doesn’t bother me at the MLP. In fact, I cannot hear it in the MLP. The problem is right now I am getting distortion on the center channel when watching a series in Netflix. The audio track is Dolby Atmos, and I think it could be related to the sound leakage from the mains.

What could be the cause of the leakage? I also have a Crown XLS1002 and it also gets the leak from the mains. When I turn off whatever crown is connected, the sound leaking and coming out through the center stops. I considered getting a new amp but should definitely identify the source of the problem first.

How should I proceed in order to diagnose the issue?

Thanks in advance.

 

[Deleted member 48726]

What if you run the center directly from the AVR and not through the crown?

What DSP profile if any, have you chosen when listening to music?

Has the problem always existed or is it new?

What is the source when listening to music?

 

[alitomr1979]

I did consider removing the Crown from the chain but never did it. I will try to do it tomorrow.

I listen to music with Roon, streaming Tidal and albums I have in my server. Somehow the leakage comes from the Raspberry pi4 or the DACs or the preamp connecting both DACs and the receiver to the Amplifier.

I think the problem has always been there.

Thank you for taking the time to help.

 

[Deleted member 48726]

I don't think running center directly from AVR does much, but it's an easy try.

I think it is the AVR itself. That's why I asked what DSP profile you use for music?
It's typical in auto. Maybe it selects stereo automatically when switching input?

What if you select pure direct?

What if you in settings tell the AVR that there is no center connected?

 

[alitomr1979]

I don't think running center directly from AVR does much, but it's an easy try.

I think it is the AVR itself. That's why I asked what DSP profile you use for music?
It's typical in auto. Maybe it selects stereo automatically when switching input?

What if you select pure direct?

What if you in settings tell the AVR that there is no center connected?

No DSP as the receiver is not handling anything when the problem occurs. Remember I have a preamp, and it receives two DACS coming from
The Raspberry, and the mains preouts frommteh AVR.

Also probably worth mentioning is that even when the AVR is not in use when I am listening to music, it turns on with the rest of the system. I have everything hooked to a smart switch, and the AVR turns on the power amp with a 3.5mm cable.

You think the leak is somehow the AVR picking the signal and sending it to the center preout??

 

[Deleted member 48726]

No DSP as the receiver is not handling anything when the problem occurs. Remember I have a preamp, and it receives two DACS coming from
The Raspberry, and the mains preouts frommteh AVR.

Also probably worth mentioning is that even when the AVR is not in use when I am listening to music, it turns on with the rest of the system. I have everything hooked to a smart switch, and the AVR turns on the power amp with a 3.5mm cable.

You think the leak is somehow the AVR picking the signal and sending it to the center preout??

Well, we know theres is leakage. We know there i a signal running from the preamp to the center via. the AVR somehow.

• What if you remove the two RCA's coming from the AVR to the pre-amp? -Center leak should definately go away.
• The signal is going from he DAC through the pre-amp to the AVR. Which inputs are you using on the pre-amp for signals from AVR and DAC?
• Is the problem still there if you turn off the AVR? -If yes, what if you pull the power cord to the AVR?

 

[Chrispy]

Leakage? What the heck is leakage?

 

[Deleted member 48726]

Leakage? What the heck is leakage?

"Spill of sound" "Leak"
Non native speaker personally. I know what OP means. You should too but chose to be pedantic. Don't.

 

[Chrispy]

"Spill of sound" "Leak"
Non native speaker personally. I know what OP means. You should too but chose to be pedantic. Don't.

How does it happen particularly? Perhaps that convoluted setup with dacs and preamps and amps and an avr? Sorry, pedantic is probably the least of the descriptors involved here.

ps Are we talking some sort of crosstalk issue? Is that "leakage"?

 

[Deleted member 48726]

How does it happen particularly? Perhaps that convoluted setup with dacs and preamps and amps and an avr? Sorry, pedantic is probably the least of the descriptors involved here.

You, with first comment, chose to adress the wording as the only thing. That's pedantic.

 

[Chrispy]

You, with first comment, chose to adress the wording as the only thing. That's pedantic.

Sorry, it blew my mind at the moment. So is it the convoluted setup and/or crosstalk or ?

 

[alitomr1979]

. Nice job on the schematics!! That is precisely my system! Add a “x2” in the DAC…

1. I suppose your first point is correct. Somehow, if the leak is happening through the wires, there must be something going from the preamp back to the amp, right? If thats the case, disconnecting the main preouts of the AVR from the preamp should correct the issue. Problem is I want the hone theater/stereo integration.

2. I have the pre90 with the extension. The AVR goes to the RCA input of the pre90. Both Dacs are connected to input3 (XLR) and input 4 (RCA) in the ext90 (additional inputs sold separately for the pre90).

3. I will check this later today as it is now 2:20am and Im falling asleep.

Thank you!!

 

[alitomr1979]

How does it happen particularly? Perhaps that convoluted setup with dacs and preamps and amps and an avr? Sorry, pedantic is probably the least of the descriptors involved here.

ps Are we talking some sort of crosstalk issue? Is that "leakage"?

I described “leakage”. Please recheck the OP. Thanks!

 

[alitomr1979]

Sorry, it blew my mind at the moment. So is it the convoluted setup and/or crosstalk or ?

Yes! Crosstalk is the word I needed, I think. Please do check my OP.

 

[Chrispy]

Yes! Crosstalk is the word I needed, I think. Please do check my OP.

I'd rather you explain all the connections/gear involved.

 

[alitomr1979]

I'd rather you explain all the connections/gear involved.

Here:
Post in thread 'Stereo sound leaking to center channel.'
https://audiosciencereview.com/foru...-leaking-to-center-channel.43877/post-1559094

There you hace a good schematic thanks to @Holdt

BTW, I tried to reproduce the problem today and I wasn’t getting any crosstalk. I will try tomorrow again. This is something I failed to mention yesterday, the problem is intermittent.

 

[Chrispy]

Here:
Post in thread 'Stereo sound leaking to center channel.'
https://audiosciencereview.com/foru...-leaking-to-center-channel.43877/post-1559094

There you hace a good schematic thanks to @Holdt

BTW, I tried to reproduce the problem today and I wasn’t getting any crosstalk. I will try tomorrow again. This is something I failed to mention yesterday, the problem is intermittent.

Getting a consistent result might be a good first step to determining what is going on. Your gear setup is kinda weird, so was hoping you'd explain it.

 

[kemmler3D]

My guess is also that the AVR is doing something to actively send sound to the center channel when you don't want it to.

Crosstalk is when you have electrical interference between the channels... but it is typically -60dB or lower. So it would be hard to hear true crosstalk in a center channel while the mains are playing...

The distortion while playing Netflix is also a clue. If it were something wrong with the componentry, it would happen all the time. It sounds like processing is configured wrong either at the source, in the AVR, or both...?

 

[antcollinet]

Worth looking at the possibility of ground loops - especially involving the AVR and Crown amps - possibly also including one or more of your sources.

What is the cable interconnect length between ARV and Crown amp?

 

[Deleted member 48726]

Worth looking at the possibility of ground loops - especially involving the AVR and Crown amps - possibly also including one or more of your sources.

What is the cable interconnect length between ARV and Crown amp?

Yeah, this is plausible. There would be signal going through the circuitry of both the AVR and power amp for the sound to reach the center spk. This is somewhat unlikely. Grounding problems more plausible.

--It would be fun to see if the leak to center gets worse or better with

A) Adjusting gain up and down on preamp with disconnected power amp or

B) Adjusting gain up and down on preamp with power amp on but discinnected speakers or

C) Adjusting gain up and down with all connected as usual.