Hissing Tweeters?

[ifarrell]

I have a HK AVR7200, with Ascend CMT-340M mains, a CMT-340C center, and CBM-170 surrounds. Even on low volume (-25db) there is a barely audible hissing, noticible from a few feet away, coming from all the speakers tweeters, most noticably the front and centers. When hooked up to an input source (toslink or SPDIF, from my audigy 2 zs soundcard) the hissing is louder, now barely noticable at -40 db or so.
If the volume is set to 0 db the hissing is rather loud, and noticable from 10-15 feet away. Is this the equitment's natural noisefloor, or do I have problems?

On a related note, to minimize noise, is it best to turn the PC's volume low, and adjust volume on the reciever, or turn the set the reciver's volume on low, and adjust volume on the PC?

 

[mulester7]

I have a HK AVR7200, with Ascend CMT-340M mains, a CMT-340C center, and CBM-170 surrounds. Even on low volume (-25db) there is a barely audible hissing, noticible from a few feet away, coming from all the speakers tweeters, most noticably the front and centers. When hooked up to an input source (toslink or SPDIF, from my audigy 2 zs soundcard) the hissing is louder, now barely noticable at -40 db or so.
If the volume is set to 0 db the hissing is rather loud, and noticable from 10-15 feet away. Is this the equitment's natural noisefloor, or do I have problems?

On a related note, to minimize noise, is it best to turn the PC's volume low, and adjust volume on the reciever, or turn the set the reciver's volume on low, and adjust volume on the PC?

.....very good, IFarrell....you gave, right up front, quickly, your entire system, since for all you knew, your problem could be anywhere....there's guys here, who digest that quickly, and can localize your problem pretty quick....

.....IFarrell, we will hope along with you that your post/question, does not, fall into the unfortunate 3% grouping, Sir.....


.....(hands cupped)....(BUUCK, QUIT GOIN' FOR MILEAGE!!!)....(I'M HAVIN' TO STREEEETCH HEEERE!!!).......

 

[ifarrell]

I seem to have posted a little to soon... The noise problem has been isolated, sort of. If I completly mute my soundcard, the noise completly goes away, even at +10db volume. With my SPDIF output muted, the only sources I get noise from are the 2 channel analog inputs, which I am not using, and have nothing plugged into them.
At any rate, I assume I can safely rule out a problem with the speakers themselves. I would have though the audigy 2 zs platinum to have a lower noise floor, put I guess I was wrong. Maybe an M-Audio soundcard is in my future.

My second question, about where to adjust volume, still stands though.
EDIT: Also, the Logic 7 DSP modes seeem to have an amplifying effect upon any noise amplifying it twofold, where as 5 channel stereo, and other modes do not.

 

[silversurfer]

Speakers only play what they are fed...they are passive devices (ofcourse if you don't have active(self amplified) speakers.

Looks like you tracked the problem though. Always start at the source.

 

[MacManNM]

Yes, this problem is entirely the fault of your sound card. You should not be running the output of the soundcard at full gain into the amp. You should be able to find a happy medium that works. Idealy you want to maximize the dynamic range of your system. If you are still getting noise, I suggest a better sound card.