10-22-14: Atmasphere
The need for blind tests illustrates to me just how little the bench measurements correspond to what we hear. If there was greater correlation, we would not need the blind tests at all.
Am I the only one that sees the irony?
I think the discrepancies between bench measurements and subjective impressions is that the bench measurements were contrived by one mindset while we listen with a different one.
Consider: When did measurements get important? I say it was in the late '60s to accompany the introduction of solid state electronics. In the '50s and early '60s, did tube products from HH Scott, Fisher, Marantz, Dynaco, Heath, Eico, etc. specify bandwidth and THD? These measurements really came into vogue when solid state components started taking over the product mix in the late '60s. I think the engineers formulated the specs and the marketing people used the specs to convince the buying public that the SS components measured better and therefore sounded better. It became such dogma that the great offerings from C-J and ARC were laughed at for daring to allow a 1% THD.
But I haven't seen much serious challenge to the validity of these specs and measurements as they relate to human perception. Yet most standard measurements are in the frequency or input/output comparison domains, and few if any are in the time domain or amplitude domain. In other words, the specs are oriented toward sound, but not musical values.
Consider THD: It stands for *Total* harmonic distortion, intentionally lumping together even order and odd order harmonic distortion. Not too surprising, as tubes' THD favors even-order, which tends to enrich the sound. And the easy way to lower THD in an SS amp is to increase the number of feedback loops.
But every time you add a loop, you slow down the rise time, which affects the timing, a value that affects the rhythmic aspect of music but doesn't show up in test tones, the stock in trade of specs and measurements.
Another aspect of sound reproduction is resolution of small differences in amplitude, something sometimes called microdynamics. This resolution conveys the finer expressivity and interpretation of a musical piece, the one that distinguishes Horowitz from a 2nd year piano major. Based on what I hear, this finer resolution is what distinguishes analog and tubes from digital and transistors. It's easy to feel the differernce on voice or cello.
Case in point: I have the CDs of Rostropovich's Bach Cello Suites. When I played it for the first time, my wife found it incredibly irritating. Later I got the Starker LP reissue of the same works. It's one of her favorite recordings as long as it's analog. It's not really "ears" (she has tinnitus) or expectations (she had none); it's how the output affects your brain waves and emotional state.
If reproduced music doesn't create the intended emotional state, it's a big fail, no matter what the product's controlled listening tests, measurements, or spec sheets tell you.
