Neutral, transparent, warm

One more observation:

JGH was particularly bothered by and critical of a particular type of coloration, one very common amongst loudspeakers. He even came up with a term for it: "Vowel coloration." He defined and explained the term in one early-70’s Stereophile speaker review I read, and I immediately understood of what he was speaking.

LIstening as much as I do to music containing harmony singing, my first test of a loudspeaker is in its’ ability to reproduce voices "accurately". Hearing voices as much as we do, it’s easy to hear when a speaker is adding coloration to singing voices; most do, to one degree or another. When I hear vowel coloration being added to voices, the speaker doing so is immediately crossed off my list of acceptable choices. I have established a very high bar in that regard.

In 1973-4 I made recordings of my wife and young son speaking, using a nice condenser microphone JGH had reviewed in Stereophile plugged straight into a Revox A77. I also recorded (with a pair of the mics) the Jump Blues/Swing band I was then playing in, both in a rehearsal space and live in a local bar. Upright piano, electric bass and guitar, tenor and baritone saxes, my Gretsch drumset and Paiste 602 cymbals, and male vocals.

Both recordings serve as excellent references when evaluating loudspeakers, better than almost all commercial recordings, most of which have been subjected---to one degree or another---to all kinds of electronic manipulation, rendering the "accuracy" of the recorded sound unknowable. What should they sound like? Who knows?!

One notable exception are the direct-to-disc LP’s on the Sheffield Labs label. Stunning lifelike sound: extremely transparent, with incredible immediacy, dynamics, and lifelike instrumental timbres. Get yourself some, and use them for your loudspeaker evaluations. If a speaker is adding coloration, reducing transparency, or both, you will immediately hear it.

Oh yeah, I forgot some of JGH's other analogies about transparency:

In addition to the term "veiling" (thanks for the reminder emrofsemanon!), he likened lack of transparency to a layer of "scrim" (must be a term from before my time, but I get it) being inserted between listener and source.

A quality important to me in the sound of reproduced music that is closely related to transparency is that of "immediacy"---the images being "palpable", as in "reach out and touch it". Another is "forward" vs. "recessed". I think that may be more a function of frequency response than transparency, but the two are not completely separate.

I don’t know if it’s still available, but at one time Stereophile offered a little pamphlet containing all the terms used (some coined) by the father of subjective reviewing, J. Gordon Holt.

Neutral and warm refer to frequency balance, transparent does not. Think of transparency like the pane of glass in a window between you and an object on the other side. If the pane of glass is absolutely transparent, removing it will in no way change your perception of the object. If you then install a not-completely transparent pane, the appearance of the object will be effected, to one degree or another. One effect can be the glass changing the color temperature of visual images passing through it. That is analogous to a loudspeaker being cold or warm---not neutral

A way to simulate the effect of transparency and lack thereof is to take a camera with an adjustable focus lens, and alternate between perfectly focused and just slightly out-of-focus. When perfectly focused the lens appears to be invisible---the image "tack sharp"; when slightly de-focused the image of the object becomes softer, a little "diffused" or smeared. In worst cases texture or grain will be added to the surface of the image. Also, the de-focussing can reduce your ability to see depth-of-field (front-to-rear layering, as in a symphony orchestra on a stage), and objects can be smeared together. All these visual terms, concepts, and observances apply equally to the high-fidelity reproduction of music.

If a loudspeaker isn’t perfectly ’neutral" (none are), it will change the "color temperature" of instruments and voices; it will change their inherent timbre. Since all loudspeakers are short of perfectly neutral, hi-fi consumers must pick the coloration they find least objectionable. That’s why loudspeaker preference is so subjective. Many audiophiles---while appreciating the transparency of ESL’s---find them a little "cold". ESL fans find dynamic speakers too warm. It’s been this way for a long time, and probably will for the remainder of our lifetimes.

In the early days of hi-fi (post-WWII and into the 1950’s)---when dynamic loudspeakers were really bad---audiophiles were astonished when they first heard an ESL design (the QUAD ESL hit the market in 1957). I know I was. The ESL’s sounded far, far more transparent than did boxed speakers (this was before Jim Winey in 1970 introduced his Magneplanar loudspeaker, itself a planar-magnetic design). Dynamic loudspeakers have been greatly improved over the past 6-7 decades, but ESL’s still sound more transparent (imo) than almost all box speakers. Magnepans are in the middle, still not as liquidly-transparent (a JGH-coined term) as ESL’s..

And then there are horns and ribbons. ;-)