Passive Pre-amp: Improves overall sound quality??

I think Atmasphere presented a balanced (and correct) view. And thanks for sparing us the partial differential equations and first principles analysis of why passives are inherently at a disadvantage.

I have benefited from use of passives while building my system. Along the way I've used passive or passive mode pre's from Adcom, McCormack, Endler, and two from Promethius. I now use the superb Promethius Signature TVC which runs about $2800 new. This was an easy choice for me, because I use a single source and don't need phono. Before you jump out of your skins, I do love vinyl and may go vinyl at some point. My current fixation on digital is primarily driven by the enormous advantage on availability of music, and the fact that my ModWright Sony is so good.

I have been careful to assemble a system around using a passive for volume attenuation and I could care less about remote control. At this point, my system is pretty good. I'm willing to begin to consider using an active. I expect at some point to A/B the Coincident line stage (5-6K) against my Promethius. No remote, 2 balanced inputs, all the money goes toward capability that I will use. By all accounts, it is a terrific piece. I'll be happy to keep it if it beats out the Promethius, even by a narrow margin.

I've heard far more actives that I dislike than actives I like. I auditioned a 20K BAT preamp that was very good. I've heard some other less expensive BAT stuff I also thought was pretty good, but I'm just not sure any of it could displace my Promethius. Most of the rest I've heard left me with an authentic "no thanks" reaction. What some hear as "body," I hear as unnatural dynamics compared to live music--the absolute reference.

I respect Atmasphere's advocacy of properly executed actives. His position is based on math, yet he stipulates there is a pragmatic consideration also. What each person has to do in assembling a system is define their needs and priorities. For people who need a full function preamp, it probably makes sense to put a good bit of money into the preamp and build out.

I started out a Maggie guy on a limited budget, so utilizing a passive "on the cheap' made some sense.

It's funny, I was very very happy until I got a really nice active preamp. My Luminous Axiom blew everything under $1000 out of the water by far, but now that I have a nice active I can actually hear what I was missing---- primarily dynamics. Playing songs at the same volume in the beginning began to piss off my neighbors with the active when they weren't much louder with the passive. I was very happy with my passive and would use it again if I didn't have a job and means to buy something nicer. By the way, I did not like the Axiom at all with my turntable, it never sounded right.

Lets list what a preamp does:

1. source selection
2. voltage gain
3. attenuation
4. buffering (impedance matching)
5. tone control (older preamps,typically)

Now, it is up to user to define his needs,since "the simple is the better" (or Okahm's razor) principle works in audio as well!
I ended removing the 2.,4.,and 5.

When it comes to active preamps Ralph is the only designer I know that adds one more item to the list of what an active preamp should do and that is control the interconnect. As someone who is very passive friendly I can respect this point of view. If an active preamp is "acting" as a tone control then it is a flawed design or designed to perform that way, which in my opinion is wrong headed thinking, or it cannot control the interconnect and its artifacts. Transparency should be the key attribute of any preamp.

BTW I currently use a passive with my analog set up (tape and vinyl) with no issues. That is soon to change though.

While I'll agree with Sam's article about passive pre's I did have a chance to listen to that particular passive unit for several weeks and it was extremely good but I still preferred Steve McCormack's VRE-1b pre-amp and by a wide margin, which by the way only puts out 6dB of gain. There's an axcellent review that just came out here:
http://www.ultraaudio.com/index.php/equipment-menu/284-smc-audio-vre-1c-reference-preamplifier

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