-=> Quoting Kenneth Parrish to Joe Kotroczo on 31 Dec 97 09:42am <=-
-=> Subj: Re: Noise Annoys <=-
 KP> A sound card sounds far noisier on some headphones than others.
Each headphone / speaker system has it's own frequency response curve.
Because of this, some will accentuate the "hiss" more than others.
 KP> I don't understand how adding series resistance will help, though a
 KP> friend says to try it.
The theory here could be that if the amplifiers in the sound card have
a high degree of noise, the series resistance would REDUCE the amount
of signal fed to the headphone.  Because of the reduced level, the
audio output would have to be RAISED to compensate for the loss,
thereby pushing down the apparent noise level.
This can create other problems though.
If the impedance of the load placed on the amplifier is outside it's
design specs, instability can result. (not common)
The level needed to drive the headphones to the previously enjoyed
level could drive the sound card into clipping.
Note that headphones vary wildly in impedance and sensitivy.  Try
several brands.  A subtle change in frequency response would probably
do more then knocking the level back. :-)
Cameron Hall
cameron.hall@bluebeam.gryn.org | ad121@hwcn.org
Blue Beam MailServer | 905 662 5784 | Stoney Creek ON Canada | v34 FAX
--- GEcho 1.00
---------------