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Re: PC sound cards

Hi Pierre,

One observation that is worth noting when it comes to sample playback using PC soundcards, beyond the reported specifications, is that of Intel's AC97 architecture.

Most consumer, and some professional PC soundcards are designed around this architecture. The main problem with such soundcards is that ALL internal processing is done at a sampling rate of 48kHz, which means that any audio stream having a different sampling rate than this must be upsampled at the i/p buss and downsampled at the o/p. The quality of this onboard sample rate conversion can vary greatly from card to card with some soundcards producing very noticeable artifacts.

The easiest fix for this is to simply replay 48kHz samples with conversion of the samples done by a trusted convertion method, which could be a whole other discussion. To be honest, this becomes more of a factor the lower the original sampling rate is, but for high quality reproduction should at least be taken into account.


David Isherwood
Research Engineer
Audio Quality Assesment Group
Speech and Audio Systems Laboratory
P.O. Box 100, FIN-33721

> -----Original Message-----
> From: ext Pierre Divenyi [mailto:pdivenyi@EBIRE.ORG]
> Sent: 29 January, 2003 22:21
> Subject: PC sound cards
> Dear Colleagues,
> Is there  a PC sound card with specifications indicating a high enough
> quality (linearity, harmonic distortion, channel separation) 
> that would
> make it suitable for use in auditory experiments?
> Thank you in advance for any information leading to the 
> arrest of the suspect.
> All the best,
> Pierre
> **************************************************************
> **************
> Pierre Divenyi, Ph.D.      Chief, Speech and Hearing Research (151)
>                                       V.A. Medical Center and East Bay
> Institute
>                                  for Research and Education
>                             Martinez, CA 94553, USA
> Phone:             +1 (925) 370-6745
> Fax:                       +1 (925) 229-3035
> E-mail :                       pdivenyi@ebire.org
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> **************