Passive Preamps

Women???

Unsound is right, there are many threads on this. In a nutshell, if you have an excellent front end with sufficient output v, and you don't want to enhance (or degrade) what it offers than try a passive. If you want to hear what passive will do for your system (which should be nothing or next to nothing), buy a used Placette RVC ($5-650), it only has 1 in & 1 output; but it is among the best resistor based pre's and will easily sell if you don't like it.

Yup, so far I like my Promitheus ref 4 better then any active I've had. Ludimagis makes a good point -- passive by nature doesn't add any gain so you'll need a cd player or source with enough voltage to essentially feed through to your amp.

Things you will likely notice: more transparency and air.
Things you may also notice: less body and weight.

Also make sure that the input impedance of your amp is sufficient, probably at least 50k ohms. More is better, tube amps usually pair well with impedance.

Lastly there is a buttload of info on this..search and ye shall find

Also keep in mind that with a passive preamp both the length and the capacitance per unit length of the interconnect going to the power amp should be as small as possible, because of the high output impedance which passive preamps will inevitably have.

Regards,
-- Al