The Acoustical Standard (with follow-up) The Chicken and the Egg part three
Confused? Consider the statement that a component makes the sound "recessed" when compared with the real thing. There are two, not one, value judgments that can be drawn: the first is Mr. Bernstein's: ie, that the component makes the sound more recessed; the second is that the component more accurately allows the intrinsically more recessed sound within the grooves of the LP to be reproduced. Which is correct? You have no way of knowing. Read Robert Levine's review, for example, of the new Michael Tilson Thomas recording of Mahler's Symphony 3 on CBS Masterworks in this issue, where he notes that it "sounds as if each solo instrumentalist...had a separate microphone on his lap," resulting in "the most crisp, spotless Third imaginable." I suggest that a reviewer using this recording to assess the quality of components would downgrade neutral-sounding components on the grounds that they made the sound less like the sound of live music; ie, it would sound too bright. Components that are intrinsically too dull will be unjustifiably upgraded for the opposite reason.
This causal dichotomy holds true for every aspect of sound reproduction, not just tonal balance. (Visitors to either of Stereophile's 1987 hi-fi shows will remember that I devoted a whole hour's lecture to just how a recording's ability to create a stereo soundstage is altered by the microphone technique used (footnote 1). The conclusion must be obvious: use only those classical records in listening tests that have been made according to philosophy #1 above. Use program material that is intrinsically neutral in tonal balance, that has the instrumental balance that the composer intended, that is uncolored, and that has the capability to create a true stereo image.
OK, name some records that you know conform to this standard.
Difficult, isn't it? In fact, I can only think of one commercial orchestral recording that gets close to this ideal, Sheffield Lab's Firebird, with Erich Leinsdorf conducting the LA Phil (CD 24), and even that is flawed: it was recorded in what I feel was an unsuitable acoustic, too dry and with too small a volume for such a dynamic work. In fact, you have to realize that recording engineers, even when they aim for honesty in recording, are always forced to compromise some areas of reproduction in favor of others. Les Berkley, for example, reviews a new Hungaroton production of Alessandro Scarlatti's oratorio Judith this month, where the engineers chose to use microphones that were timbrally accurate. However, they also used a mic technique, probably dictated by the very natures of those microphones, that destroyed any sense of a real soundstage. Many of the Wilson and Reference Recordings are similarly timbrally accurate, at the expense of the stereo image, while recordings that aim to preserve the accuracy of the soundstage nearly always seem to require the use of microphones that color instrumental tone quality, sometimes more than a little. And many recordings, particularly those made with large numbers of microphones, both add coloration and destroy any semblance of a realistic-sounding stereo image.
What I am trying to lead you toward is a recognition that it is too simplistic—and pompous—to insist that equipment reviewers unthinkingly adopt the dialectic involving logically inconsistent comparisons to live sound. This inevitably leads to the reviewer becoming trapped in an endless loop. Rather, it is more fruitful for reviewers to base their value judgments on specific recordings that they already know have a particular character in one area of reproduction. A reviewer's initial task is one of diagnosis, and any recording is appropriate for use, not just those that can be compared to live sound, if it aids the reviewer in this phase of the review. (How else could you justify the use of non-musical test signals, for instance?)
The Clannad Magical Ring album that I mentioned last November, and that Mr. Bernstein suggests I abandon as a test record on the grounds that it doesn't have a verifiable source sound, is such an album. While it would be pointless to use this recording to examine a component's departure from tonal neutrality, I use it specifically to examine a system's ability to throw a well-defined soundstage with width and depth. The fact that it has no absolute referent is irrelevant in this respect: a system's imaging ability can be benchmarked with any recording that contains pure intensity-stereo information, and in actual fact, panpotted multi-mono rock recordings tend to be more informative than a typical classical recording, as almost none of the latter are recorded so as to encode this information. (The only exceptions are recordings made in a pure, coincident-figure-of-eight manner or in a variant of the M-S technique, and these are rare beasts indeed.)
In addition to the intensity-stereo lateral imaging contained on Magical Ring, the fact that its producer has used sophisticated artificial reverberation enables a good system to present considerable image depth. There is no need for a comparison with live "images" here; the fact that the recording possesses the requisite information makes it a sufficiently sensitive test. If I hear the attributes of specific lateral image position and well-defined image depth with Magical Ring, I then know that any classical recording will reproduce with the maximum image specificity of which it is capable. The reverse, Mr. Bernstein—if, say, I use a typical orchestral recording from one of the major companies as my benchmark record—will not be true.
Footnote 1: I was intrigued to read in the November/December 1988 issue of The Absolute Sound that pianist and educator James Boyk is offering a commercial cassette, realized by some of his students at Caltech, which appears to be based on my series of lectures on how different stereo microphone techniques affect the reproduced soundstage. Readers interested in acquiring this tape should contact Mr. Boyk at Performance Recordings, 2135 Holmby Avenue, Los Angeles, CA 90025-5915. Tel: (213) 475-8261.