Rich May of Sumo: An Audio Dynasty Page 5
May: And even the board layout is extremely critical. Minimizing the amount of loops within the grounding circuitrynot ground loops per se, but how the signal flows in the boardis a major problem. A fully differential amplifier, if well designed, is immune to things floating around on the ground because the amplifier is only measuring the differences between two inputs.
Atkinson: Professionals have worked balanced for a long time. Why is it only now that this is being worked into consumer products?
May: For professional applications, they throw a transformer in there. But we've got to do it actively. Actively and discretely. One of the biggest tasks that I face in doing that is finding a low-feedback, unity-gain inverter so that I can provide an inverted replica of the signal.
Atkinson: For LP playback, you can arrange to have a balanced output from your cartridge. You have both in-phase and anti-phase outputs from the cartridge.
May: You do have a handle on the two ends of the cartridge. Unfortunately, a moving-magnet is not well-balanced capacitively to ground. It is not a symmetrical signal. Now, on a moving-coil, yeah. I would very much like to come off a moving-coil cartridge differentially, and use a number of matched paralleled transistors to get the minimum possible noise; operate with relatively high currents and keep it differential all the way through the preamp and the power amp.
Atkinson: When it comes to listening to what you've designed, do you worry that you can find yourself liking something which is actually wrong? For example, if you add second-harmonic distortion to the sound without too much intermod, the sound actually gets rather fat and soft and blurry, which some people appear to like. How do you keep yourself on track?
May: You have to have a handle. Again, it's where you start correlating between what you measure and what you observe.
One of the things I'm very cautious about is that the vast majority of my listening is done on carefully selected big-band or classical material. Rarely do I listen to popular material. A very good friend of mine, Larry Philips, who was with JBLa superbly creative individualcame up with an absolutely beautiful analogy. Popular recording is an impressionistic art form. The monitor loudspeakers are your canvas, the microphones your paintbrushes. The equalizers, level controls, limiters, compressors, reverberators, clippers, or whatever, are your color palette. And any similarity between what exists in reality in the studio and what's laid down on the tape and presented on this acoustic canvas is entirely coincidental.
And it is so true. You look at the things engineers use, like Kepex, or Gain Brains, or 20:1 limiters, or multi-mikes. There is a line that drives me up the wall: "It sounds like hell now, but we'll catch it in the mixdown."
I have some big-band recordings that were done over at Capitol. Multi-miked: they are absolutely two-dimensional. Yet Creative World released a three-mike stereo recording of Stan Kenton in concert back in Ohio in 1959 that is so utterly unbelievable sonically, it's three-dimensional. Totally three-dimensional. In "September Song," a woman in the audience, it sounds like she's been smoking for 55 years, coughs. And people who are listening to this record whisper, "What the hell was that?" Talk about being captured live. Or Ed Green. When he was with MGM, he recorded Sinatra in quad, the special with Sinatra that Magnavox did sometime in the '70s. Ed's recording puts you about five rows back, with the audience behind you and the performance in front of you: you were immersed in the hall, and it was overwhelming.
I'm not as negative as I seem to be about rock; it's an art form. Certainly it's a money maker. But if you've got engineers who have come up in this art form with a philosophy of "We'll catch it in the mixdown," do they really appreciate or understand?
Atkinson: It's ironic that in an age when we have the technology to do just about anything we want, the intrinsic quality of recorded sound, as opposed to reproduced, seems to be getting worse.
May: I can't give a good answer to that. I posed a similar question to John Eargle: I asked why is it was that the Europeans had done all the research into microphone placement for two-channel stereo recording? [footnote 1] And John said, "Well, stop and think about it this way. They have more access to live music in good halls in Europe. Where does the average American interested in classical music go to hear a live performance?" Where do we go in southern California? The Dorothy Chandler Pavilion? The Ambassador Auditorium? The Hollywood Bowl, where they have a sound reinforcement system? We don't have the reference. We don't have the exposure on which to base our judgments.
Atkinson: So modern recording just chases 'round in circles, farther and farther from the real thing.
May: There is a classical recording which sticks in my mind. I have a Mercury original Nutcracker, Minneapolis Symphony in mono. I have access to the same recording in stereo. Three microphones, engineered by Bob Fine. I hear more inner detail in that orchestra in the mono recording than I do in any of the recent multi-microphone recordings. Absolutely without question. Now, I'm not saying that you don't hear technical limitations in the stereo recording. You hear the cutterhead, which had severe problems. But, oh my God, you want to listen to it. There was a Capitol recording back in the days of monoDances Sacred and Profane and Introduction and Allegrorecorded with a single Altec 21C microphone with the performers just circled around it. Absolutely flawless from an acoustical standpoint, from the point of listening to a performance. Even though, technically, you'd laugh it off now because of the inherent equipment limitations.
Atkinson: If you go into a record store and buy classical records at random, there's no correlation between the recording date and the quality. Though it is possible to make very fine recordings nowadays, the chances are that they won't be.
May: I've gone for two months now without buying a record. A sad commentary.
Footnote 1: One of the only exceptions being John Eargle.John Atkinson