Passive Preamp?

I wouldn't know where to begin with such a vague question. What is it you want to know?

There is a lot of discussion about these in the forums. After you search through them perhaps you can come back and ask something a bit more specific that pertains to your particular situation.

A search of the archives will yield all the info and opinions you need. Passives can be had cheap enough that an audition in your system will tell you more than any written words can convey. Many feel passives lack dynamics but again, the sonics are very system-dependent. Set up properly, they can offer great sound that may be incomparable to an active piece. As always, YMWV.

Do a search here and at AudioAsylum,all the info you will ever need on passive preamp is here and there

A passive preamp has no amplification stage. It is actually something of a misnomer. Typically they do not plug into an electrical source. I own two of them and they are both just switch boxes with a volume control. If you need more than this fundemental info, then you should follow Herman's advice above.

Check out the thread at: http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1159194844&read&keyw&zzno+regrets