Irritating "whistle" on right channel from SB3

[davis]

I've had my SB3 for approximately one month now, and I'm loving it.

However, I can hear an odd whistle in the right channel. I've done a bit of cable/port/source swapping and it would appear to be caused by the Squeezebox. The whistle's also on the headphone output.

About the noise:

It's pretty damn high (so I don't think it's a ground loop), but really quiet. It's pretty close to the top end of what I can hear, and it's only present with the squeezebox on. The left channel is pretty much silent.
The noise is also always there (when the SB's on, obviously), so I don't think I'm hearing fridge compressor motors or anything.

Normally I like to think I'm quite good at debugging this sort of thing, but I'm completely stumped now... does anyone have any ideas or tests which I can do?

cheers

[opaqueice]

You could try dimming the display - is the sound correlated with the brightness setting?

Another thing is to move the SB around while listening with headphones. Does the sound change depending on where the SB is located?

[davis]

You could try dimming the display - is the sound correlated with the brightness setting?

Bingo! A shiny pint for the man in lead boots and concrete trilby!

Thanks very much -- it was the display. Turning it off kills the noise. I think I'll probably make the display auto-off while playing in that case.

Thanks again.

[Eric Carroll]

However, I can hear an odd whistle in the right channel

I reported exactly the same issue in http://forums.slimdevices.com/showthread.php?t=32045.

My problem is exactly correlated to brightness display as indicated in my post.

I am going to add -20dB attenuators because my SB3 is directly connected to my power amp. I am hoping this will attenuate the problem noise as well.

Could you describe your system configuration? Are you, by chance connecting to a power amp directly without a preamp? Are you by chance mismatched in your line levels?

So far noone else but you and I have reported this.

[davis]

Could you describe your system configuration? Are you, by chance connecting to a power amp directly without a preamp? Are you by chance mismatched in your line levels?

My SB3 is plugged directly via RCA/Phono cables into a NAD C372 integrated amp, driving a pair of kit-built North Creek North Spirits. I tend to leave the amp at half-volume and use the SB3's volume control.

As for mismatched levels, I'm not sure I can adjust anything... but I don't think I understand the question.

[Eric Carroll]

My SB3 is plugged directly via RCA/Phono cables into a NAD C372 integrated amp, driving a pair of kit-built North Creek North Spirits. I tend to leave the amp at half-volume and use the SB3's volume control.

As for mismatched levels, I'm not sure I can adjust anything... but I don't think I understand the question.

Mismatched levels is about the output voltage of the SB3 (2Vrms) vs the input sensitivity of the power amp.

In your case, you indicated you have a integrated amp, so you have a volume control to adjust the levels with. So, to be clear, you have the SB3 digital volume control set near full volume and the NAD volume control set half way?

Out of curiousity, do you hear this tone while music plays or just in the silences between tracks?

[davis]

So, to be clear, you have the SB3 digital volume control set near full volume and the NAD volume control set half way?

I tend to leave the amplifier at half-way, unless I'm trying to destroy the windows. I use the SB3 analogue outs and adjust the volume with the SB3 remote. The volume control works out as approximately:

10% Quiet background music.
40% Where I actually start _listening_
60% Probably what I'd call "loud enough".
80% Fills the house.

Out of curiousity, do you hear this tone while music plays or just in the silences between tracks?

I've only actively *heard* it in the silence. I can't consciously hear it when the music playing because it's simply buried... but I haven't conducted any blindfolded tests to see if it's better with the display off versus display on: I just have the display auto-off after a bit.

[Eric Carroll]

I've only actively *heard* it in the silence. I can't consciously hear it when the music playing because it's simply buried... but I haven't conducted any blindfolded tests to see if it's better with the display off versus display on: I just have the display auto-off after a bit.

What volume were you using on the integrated amp when you hear it? Does the volume control make a difference? i.e. can you hear it at 10% or does it only get discernable at a higher volume?

[peejay]

I've had my SB3 for approximately one month now, and I'm loving it.

However, I can hear an odd whistle in the right channel. I've done a bit of cable/port/source swapping and it would appear to be caused by the Squeezebox. The whistle's also on the headphone output.

About the noise:

It's pretty damn high (so I don't think it's a ground loop), but really quiet. It's pretty close to the top end of what I can hear, and it's only present with the squeezebox on. The left channel is pretty much silent.
The noise is also always there (when the SB's on, obviously), so I don't think I'm hearing fridge compressor motors or anything.

Normally I like to think I'm quite good at debugging this sort of thing, but I'm completely stumped now... does anyone have any ideas or tests which I can do?

cheers

Given that neither I, nor others on this forum have this problem, and that it occurs on the output of the headphone jack - meaning it is completely internalised to the SB3, I'd suggest that this stray oscillation or whatever it is, is perhaps the result of a component out of tolerance, or some other fault, which would cause me to return it for a swap.

[opaqueice]

I have this too, although it's too faint to be noticeable normally. Try turning up your amp's volume all the way and put your ear close to the right tweeter with the SB idle.

I suspect all SBs do this, it's just that some people have greater gain on their amps, more sensitive speakers/headphones, quieter listening rooms, or better hearing...