NB: The following is all my opinions. I am not a master on MP3 compression. I understand none of the details of it. Most of this is from my friends experiences. MP3 isn't stored as individual samples and thus bitrate and sample rate are not directly relevant. But yes, MP3 decodes to 16bit. As to whether or not it is sub CD-quality that is another question. Yes there is less audio information than CD quality (16-bit 44kHz) but MP3 uses psychoacoustical rules for it's compression. The basic premise of this is to analyze the way ears work and send enough information of the right type so the ear gets the same info. i.e. you may only send a 1/4 of the information on a CD but that's enough for the ear to get 90% of the sound. In my opinion two major things that effect MP3 quality are the bit rate and cutoff. The bitrate is analogous to the quality of the sound. According to most info 128 MP3s are labelled as CD quality. From experience I would suggest you use at least 160. 160 provides a fair increase in quality for a small size increase. That's not too say I can tell the difference easily between 128 and 160 but I'm convinced it's there. One of the main differences is 160 has much better stereo than 128. Most of my MP3s are in 160 and I find them to be of highly acceptable quality. I rarely if ever notice a major difference between 160 and CD. Cutoff is what is going to butcher the quality of your MP3s. Cutoff is largely determined by the encoder you use. DO NOT use the Xing 1.0 codec it has horrible cutoff. Go for the Fraunhofer Professional codec or for speed the new Xing Codec included in Audio Catalyst, it is fast and of fair quality). In terms of soundcard it shouldn't matter too much. There will be a decrease in quality of course but you are unlikely to notice it. My friend has an SB16 which ain't exactly high quality yet he is able to pick the cutoff of a given MP3 by ear. Thus, I would suggest the SB16 is high enough quality (if you can ever use quality and SB16 in the same sentence) for MP3 playback. If sound card quality is an issue then I would suggest you don't use MP3 as if the difference between 2 low end soundcards bothers you, the difference between MP3 and CD will almost certainly bother you. Tom. ----- Original Message ----- From: Steve Ridley Subject: Re: [OT] sound cards, spdif, etc > I would like to use a PC to play MP3. Is there a sound card that is better > suited for this purpose. I am aware that MP3 is 16 bit and sub-CD quality. I > just wondered if there are sound cards and sound cards. Even at this > distance from professional quality.