speaker hiss

[blakerwry]

I figured we had some electrically inclined people here... especially relating to audio.

I have an Altec Lansing ACS56 4.1 computer speaker setup. My problem is that when the system i on there is audible hiss coming from the 4 satellite speakers. This happens at any volume level, even when the speakers are isolated from any outside electronics. This happens even if there are no inputs from the sound card to the speaker system (inputs connect to the subwoofer).

So I'm pretty sure the hiss is generated by the speaker system itself. The hiss is audible because the speakers sit relatively close to me while I'm at the computer(within 3 feet). I'd like to remove this hiss. Is their any way to do this(maybe some kind of inline filter I can add?).

 

[blakerwry]

BTW, a google search for ACS56 and speaker hiss did turn up some results that show other people have experienced the same problem with this set of speakers as well as a preceeding model.

 

[blakerwry]

The hiss is more aparent when using the surround speakers vs just the fronts

 

[Mercutio]

That distortion may be introduced as part of the matrixing process Windows uses to upconvert stereo to quad, although I believe others here on SF have complained about hissing Altec Lansing speakers as well.

Does that set offer any kind of digital input? Have you tried the speakers on different sound hardware (e.g. a Live!, if you're using onboard sound, or vice versa)?

 

[time]

If it's happening at any volume level, I'd have to say the speakers are defective. Usually, the amplifiers will be organized as two per IC (fairly confident this is the approach based on the advertised power level). Logically then, the two 'surround' speakers will share the same - presumably noisy - chip.

Altec Lansing publishes relatively realistic ratings. If the units are under warranty, I'd certainly have a chat with them about the product not meeting the claimed standard.

I've definitely not noticed a problem with any of the three different Altec Lansing models I have here at present, but two are more upmarket and the third is on the floor where I probably wouldn't notice anyway. Plus they're all 2.1 configuration.

I guess it's also possible that your house is as quiet as a crypt and you have ears like a bat. How close are you to these speakers anyway?

 

[blakerwry]

That distortion may be introduced as part of the matrixing process Windows uses to upconvert stereo to quad, although I believe others here on SF have complained about hissing Altec Lansing speakers as well.

Does that set offer any kind of digital input? Have you tried the speakers on different sound hardware (e.g. a Live!, if you're using onboard sound, or vice versa)?

Like I said merc. It happens even when not connected to the comptuer. It does offer PCM coax for the front two speakers, but not the rear. However, my sound card only has optical out for digital connections, so I'm just using analog.

The front speakers actually don't bother me (hiss is not noticable unless I'm within a few inches or it's very very quiet) It's the surrounds that bother me. I don't have the surrounds even attached right now because of it.

I don't think it's the speakers, I think it's a signal coming from the amp... I guess I could hook some headphones up and see if I hear the same hiss.


I haven't thought of talking to Altec, I got the speakers as a floor model so I didnt get a warranty at the place of purchase... hmm.. I might have the reciept around here, but I doubt it.

 

[Mercutio]

I've found it difficult to get RMAs for inexpensive sets of speakers in any case. I ended up throwing away several pairs of Yamahas and Creative Labs speakers after not being able to get an RMA.

 

[time]

True enough, Merc. I don't even try to repair the more expensive units these days, either. I just can't see how it's worth the time and hassle.

Blake, speaker drivers don't contribute noise. It has to be the amp - or more accurately preamp - stage. Unfortunately, I can't think of anything you can do about it.

Be careful wiring headphones into speaker connections (I think that's what you're planning?). They're much lower power and are easily ruined.

 

[blakerwry]

I wasn't going to play any sounds... just plug in and listen for hiss... you're right though. I certainly wasn't going to plug a nice pair of headphones into the system.

I thought perhaps there was some kind of inline filter I could add (like a resistor) that would, in effect, lower the sensitivity of the speakers so that the background hiss was lessened to an inaudible amount.

 

[jtr1962]

It's a stretch but you could be picking of 60 Hz line noise because of the speaker wire acting as an antenna. Only thing that might help is changing all the connections to shielded wire, and even then I'm not sure. The amp should have had filters to reject 60 Hz to prevent just this sort of thing.

On a somewhat related not, my speakers sometimes start hissing or making other noises whenever I'm on the Internet. I still don't know if this is related to a bug in IE, Windows, or something electronic. I can always cure it by doing something that causes the computer to make a sound (i.e. clicking on a link).

 

[i]

Don't discount the obvious ...


... have you checked for snakes?


Surely that's the number one cause of hissing speakers.

 

[blakerwry]

lol, i was reading through some forums and a guy said his new computer wouldn't turn on.... I almost replied back to him asking if it was plugged in... i managed to stop myself... but I thought it was pretty funny.

 

[i]

Drat you, blakerwry! :lol:

I was trying to get to sleep when your post popped back in to my head. Evil humor is the best sometimes, but in my progressively sleep deprived state it seems I'm starting to have flashbacks...

"I can't turn on my computer!"

"Have you tried some sexy lingerie?"

 

[blakerwry]

now that's comedy

 

[Jan Kivar]

"I can't turn on my computer!"

"Have you tried some sexy lingerie?"

:mrgrn:

Jan