I know some audio lovers who prefer the first PSX's as a source than any cdp...
Here's a few good links about psx mods.

http://www.modchip.ca/install/ps/index.php

http://www.methe-family.de/cd.htm

Modifications and repairs on a Sony Playstation SCPH1002

by Mick Feuerbacher:

http://dogbreath.de/PS1/index.html

Removal of "the chip" in a Sony Playstation SCPH1002

http://dogbreath.de/PS1/ChipRemoval/Chip.html