The above mentioned books are excellent reads. If you are lloking for something lighter: This book- (http://cgi.ebay.com/The-Complete-Guide-to-High-End-Audio_W0QQitemZ280332119531QQcmdZViewItemQQptZUS_Nonfiction_Book?hash=item280332119531&_trksid=p3286.c0.m14&_trkparms=72%3A1205%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318%7C301%3A1%7C293%3A1%7C294%3A50) Contains some good, basic and practical info about tubed pres, amps, DAC's, etc., their circuitry and what to look out for when auditioning. That's besides all the other great info concerning the entire system/listening room acoustics/etc.
