Lightspeed Attenuator - Best Preamp Ever?

I understand why a moving coil cartridge would need gain (and RIAA equalization) to create a sense of drive and dynamics, but why would a 2 volt signal need any gain to drive an amp that plays at maximum output with 1v of input? Is "drive" something different than simple voltage which is either sufficient or insufficent to drive an amplifer? I suppose a source could have a weak output stage, but I would think that would be as much of problem for driving an active preamp as a more direct connection to the amp. There is something appealing about "horsepower", but does it really serve any purpose where input sensitivity is simply not an issue? Does an active really provide something "in reserve" for hearing micro and macro dynamic inflections?

Sources these days, esspecially CD can drive (have enough output) by themselves (without the need of a preamp) a poweramp into cliping, there is your strait wire with no gain (the interconnects only).
All we need is something so we can attenuate that source so it doesn't blow the amp up, we do not need a preamp that preamplifies again on top of the source that can already by itself blow an amp up with the amount of output it has.

Cheers George

Pubul57

Good questions and they reflect what I am trying to better understand. I am not an expert on these technical questions and feel the questions are reasonable, but would like a better understanding of this topic.

Both Publ57 and Fiddler argue, I think, that the live performance is not relevant to the LSA because (in Publ57’s case) the LSA connects directly only with the output of the TT/arm/cartridge/phonostage, and because (in Fiddler’s case) “We have no control over what happened in the studio, therefore, that discussion is a non-starter for me. I can't change a single decision made during the recording process. I can only try to extract the information from the recording as accurately as my equipment will let me and change the sound of it to the degree that I want to KNOWINGLY change it.”

Of course, I agree with their premises, but I don’t think the conclusion follows.

If we understand ‘source’ generally to mean ‘the standard by which we should evaluate a piece of equipment’, then I think the live performance should serve as that standard—and not either the information codified on the vinyl or the output of the TT/cart/stage. I think Marqmike’s post serves as a reminder of this truth, a point I’ll return to below.

I don’t think the vinyl (or output of stage) can serve as standard because we don’t (can’t?) know what it contains except through ‘corrupting’ electronics (I take it this is part of Knghifi’s point that “Every component has a sonic signature.”). Suppose Claire, using a LSA and other purported neutral and natural sounding equipment, judges that some vinyl sounds like X, Y and Z (fill in with your favorite audiophile vocabulary). She proclaims triumphantly, “I finally got it; the vinyl as it actually is, all the information it contains has been transmitted through my system.” Suppose Claire now swaps out the LSA and puts in a different passive preamp (say the McCormack TLC-1) and plays the same disk again (all else remaining the same). It sounds different (X, A, B; no or diminished Y and Z), and she swears “this time I’ve finally got everything, nothing added, nothing lost.”

Question: on what basis can she decide which judgment is correct?

Remember that this is not a question about which she prefers but rather about which is truer to the information codified on the vinyl or the output of the stage (after all, that’s what she’s after). She can go through many iterations of the above scenario trying to find the one preamp true to the vinyl, but she can never find an adequate basis for justifying any particular judgment because this method does not allow for any external point of view. It will be just more equipment, all sounding great and ‘neutral’ but, alas, different. [it is conceivable, contrary to my hypothesis, that the two preamps deliver the exact same sound—that might serve as confirmation that they had arrived at the truth. I leave that possibility aside because I’ve never heard two different pieces sound exactly the same. “Every component has a sonic signature.”).]

The point Marqmike makes in his post can now play its role. The way to adjudicate between the competing judgments is to assess which comes closer to what instruments played live sound like. This is the ‘external’ point of view. The reason the LSA is true to the vinyl is that it best approximates what instruments actually sound like. Live play serves, then, as the standard of evaluation and ultimate source (this part jibes with how Publ57 describes it).

I experienced something like when I switched from the passive I used to own (TLC-1) to the LSA. The McCormack was a well-received preamp when it came out and I found it a good product. When I got the LSA (as a result of reading this thread) I noticed immediately a warmth and fullness of sound that wasn’t there with the McCormack. Did the LSA add that warmth or did it merely reveal what the McCormack couldn’t? I decided to keep the LSA precisely for the reason Marqmike described: it better approximated the sound of actual snare drums, pianos, etc…

When I used to live in NYC I had season tickets to the Met. My last year there Tristan and Isolde was on the program and I recall very distinctly the sound of the opening notes (as played by a James Levine led orchestra). I was really moved because the orchestra had not ever sounded like that in the times I had gone before. Recently I bought the Furtwangler and Bohm recordings of the same opera and my test was whether the McCormack or LSA could bring me back to that sound. The LSA won and that another reason why I kept it. (of course, that sound never really came to me, even approximately, because my system in total is not good enough).

I tell this story because I conjecture that many of us have a sound we experienced live and we use it, consciously or not, to assess the comparative quality of equipment.

Lest I again be accused of dispensing too much jabberwocky, I include a banal jabberwocky-free report on the LSA:

A couple of weeks ago I was considering buying a new phonostage (the tubed Allnic h1200). I wondered about its compatibility with the LSA and so emailed George the manufacturer’s specs. He told me the output impedance at 1.2 kohms was “a bit too high”, but that he had had other customers who had DACs and phonostages with impedance that high and they had no problems. Slightly hesitant but impulsive by nature I bought the Allnic. I’m sure glad I did because it sounds fantastic and, as far as I can tell, plays well with the LSA. What am I supposed to be losing if the output impedance is too high? The lesson is that even though the numbers may not look promising from a compatibility point of view, it may be worth trying nevertheless.

Publ57: I had a suspicion you were a philosopher; what subjects did you study? (I specialized in moral philosophy).

History of... then Phenomenology - Stony Brook was very "continental". There is a very interesting thread out there on whether the best stereo reproduction is 5% of "real" or %95; I am not sure the %, but no stereo has ever fooled me into thinking it was real, unamplified, acoustic instruments. Yes, what I most want for the system to sound most like the "absolute" sound of the real thing, but I give an awful lot of weight to the recording process in capturing all the vital cues that makes the real sound so distinct form the reproduced. It took me a few years to not be disappointed listening to my stereo after coming back from a live performance at the Blue Note or Vanguard. Like looking for good food in London, I thought it was just a matter of throwing more money at the gap, I concluded it is just the inherent difference between live and Memorex, and I have learned to love recorded music for what it is.