Active or passive preamps?


If passive preamps add nothing , then it should be the purist to the origianl signal, so why audiophiles want active preamps? And then is it true that all the passive preamp are created equal? Thx.
kitty
One source for DIY passive preamps is www.goldpt.com. Arne Roatcap has designed Elma switches with circuit boards, in various configurations, and has at least one schematic for a passive. He's a helpful source of advice too. If you want info from me on what I've built, email nicetom@sonic.net. I used Elma switches once, Shallco several times, from either The Parts Connection or directly from Shallco.
Kitty- Checkout Michael Percy Audio at (415) 669-7181 for passive components and kits, and active kits for the DIY. I've used both types in my audio past, but always end up back with active (tube) pre-amps. However, the cost of a great tube pre-amp can be rather high even if you build it yourself. Keep in mind, the passive approach is limited by the length of cables, the output impedance of the sources and the input impedance of the amp(s). Goodluck.
Thx for all the inputs. My system include Sony SCD 777es and Simaudio Moon W-5 , the spkers is Maggie 1.6QR. I am looking for the preamp right now, can I go with a passive preamp? Or I have to go for a active preamp? Any suggestions? And thx.
Try Placette ($1,200) ther designer claim its superb with SACD. 30 days money back warranty. If you will do it - please report results