consensus on passive preamps?


If you've had a passive preamp in your system what was the final verdict?
hbarrel
I owned a Silver Rock Passive with the 0db gain. They also make one with 6db gain. It uses a completely silver wired transfomer / potentiometer. I've had other passives, and I agree with most of the comments here regarding the drawbacks of passives. But the Silver Rock has none of these issues. It is the most transparent pre-amp I've ever heard, and shows none of the weaknesses of passives. It is dead quiet, as it acts as an isolation transformer as well as a pre-amp. For more info, please read the TAS review of it where they compare it to a $15000. active, and also the TAS review of the Halcro amps where they used the Silver Rock with them. It is expensive for a passive and looks like hell, but it sounds great! I sold it because I went to a Tact (2.2X).

A bit off the subject, but I'm very surprised that Marakanetz didn't like the 2.0. I've set-up two 2.0s for friends (they don't have laptops), and the Tact is stunning. Both of these guys now agree with me that the Tact is a "must have" in any system. I also thought that the volume control was completely transparent when the Tact was used only for this purpose. We went back and forth with it in and out of the system using a passive and an active pre-amp. Perhaps you could comment further on what you didn't like about it?

Successful use of a passive preamp is system dependent. In a highly resolving system the passive should be more accurate to the source signal. The ideal "passive preamp" simply attenuates the source signal without capacitors or transistors (which change the sound). Therefore the signal retains more of its original flavor and sounds less processed and more pure. Loss of bass and dynamics is a due to a mismatch between output level and input impedence.

Ideally, the attenuator should be built into the source component circuit for the most accurate sound. This is because source signal does not have to travel through simply another component (less circuitry), and there is one less connection, and one less interconnect. It appears that some manufacturers realize this, like Audio Aero and Resolution Audio.
Well said, Ultrakaz. In my current situation all I upgrade is only and only source since I've set up the correct amp/speakers for the listening room. Any attempt to bring in active preamp wasn't successful at all. The bass was tighter but the deapth and imaging were missing a lot.

BTW: Are you sure that Audio Aero and Resolution Audio have an analogue passive attenuatter instead of digital?
Yes, the Audio Aero and Resolution Audio both use an "analogue" attenuator as opposed to a digital one. I think Wadia and Accuphase use a digital one. This, of course, is important because it subtracts information to attenuate the sound.
I have FT-Audio LW1. Much better than with pre, which adds noise and veil as well as bass. I now use Cary 306/200 with ANALOG volume option, and connect directly to the amp. Similar, but more convenient than having passive, as I have only one source.
The statements above are only to my ears, with my system, in my room. As always, you have to try in your room with your system.