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takashi37
2005-06-10, 22:10
Sorry for the somewhat crass subject line, but that's really the best way to describe this.

As it says, I'm getting an intermittent "fart" noise through my setup, which is SB2 line out to a pair of inexpensive Boston computer speakers.

ADDENDUM: After further listening, it's really sort of two noises in rapid succession, a small squelch, followed by a small reverberant puff. It varies in loudness.

The thing is, the noise sometimes happens even when there's no music playing.

Any thoughts appreciated,
TL

Mike Scott
2005-06-11, 05:31
On Sat, 2005-06-11 at 00:10, takashi37 wrote:
> Sorry for the somewhat crass subject line, but that's really the best
> way to describe this.
>
> As it says, I'm getting an intermittent "fart" noise through my setup,
> which is SB2 line out to a pair of inexpensive Boston computer
> speakers.
>
> The thing is, the noise sometimes happens even when there's no music
> playing.
>

It could be some electrical device (aquarium heater or such) nearby or
on the same circuit inducing noise onto the power line. If you unplug
the speakers from the SB does it still occur?

You might try moving the setup to another area to see if it still makes
the noise. If it is power line-induced, you might try a filtered power
strip. If it's RF induced, you may need to add filters or shielding to
the cables so they don't act as antennas.

--
- Mike Scott
- mscott (AT) pyewacket (DOT) org

takashi37
2005-06-11, 07:44
On Sat, 2005-06-11 at 00:10, takashi37 wrote:
> Sorry for the somewhat crass subject line, but that's really the best
> way to describe this.
>
> As it says, I'm getting an intermittent "fart" noise through my setup,
> which is SB2 line out to a pair of inexpensive Boston computer
> speakers.
>
> The thing is, the noise sometimes happens even when there's no music
> playing.
>



It could be some electrical device (aquarium heater or such) nearby or
on the same circuit inducing noise onto the power line. If you unplug
the speakers from the SB does it still occur?

You might try moving the setup to another area to see if it still makes
the noise. If it is power line-induced, you might try a filtered power
strip. If it's RF induced, you may need to add filters or shielding to
the cables so they don't act as antennas.

--
- Mike Scott
- mscott (AT) pyewacket (DOT) org



Thanks Mike. Will try these things and let you know how it goes.

Are most power strips filtered?

pfarrell
2005-06-11, 08:09
On Sat, 2005-06-11 at 07:44 -0700, takashi37 wrote:
> Are most power strips filtered?

Not in any meaningful way.


--
Pat
http://www.pfarrell.com/music/slimserver/slimsoftware.html

seanadams
2005-06-11, 10:57
I expect you'll find you still get the noise even if you unplug the audio cable. In that case it's the speakers - a few (cheap) powered speakers are sensitive to RF, be it 802.11, cell phones, baby monitors, etc.

Since the RF is intentional communication traffic, the only solutions are to put the speakers farther away, get better speakers, or use ethernet instead.

Or try Beano... :)

jaw
2005-06-13, 17:42
I have heard this sound.
sort of a two-part brip-brap "fart".

I do not own the same speakers as you do, so we can
probably rule that out.

I suspect it is a surge from a large electrical device
somewhere (A/C, elevator, ?) but I have not been
able to track it down.

seanadams
2005-06-13, 18:38
I have heard this sound.
sort of a two-part brip-brap "fart".


I'm pretty certain it's not coming from Squeezebox's audio outputs. If it's the noise I'm thinking of, it's the 802.11 traffic being picked up by the amplifier inside the speakers.

Try disconnecting the analog outputs and turn up the volume on the speakers to test.

rds
2005-06-13, 19:43
It's definitely related to wireless RF as Sean suggests. When I had Cambridge Soundworks speakers connected to the SB2 in my bedroom, I did not experience this problem at all. However, I did experience it on a pair of headphones that I plugged in, leading me to believe that I had a faulty headphone jack. About a week later I swapped the white Cambridge Soundworks speakers with a set of black Altec Lansings (for purely aesthetic reasons) and immediately noticed the problem with the new speakers (which evidently are not as well-shielded as the Cambridge Soundworks speakers). I finally clued into what was causing the problem when I switched off the SB2, causing the clock screensaver to display. I noticed a clicking sound coming from the speakers that was in perfect sync with the changing seconds on the clock display. Since this gets remotely updated from the server every second, I assumed the problem had something to do with the wireless connection. I disconnected the external RF antenna, which caused my signal strength to go from 96% to 80%, but which also elminiated the RF interference with the speakers/headphones.

Dean

takashi37
2005-06-14, 13:14
Okay, so I have determined that speakers still fart even when disconnected from the SB2.

Going to try removing the antenna as Dean suggests to see if that works.

Last resort will be to buy new speakers -- even though I'd really love to buy new speakers :)

Thanks again for all the replies.