The Stereophile Test CD Letters part 3

The Test CD results

Editor: I had as much fun toying with your first Test CD as I could see that you had in producing it. Ralph, the dog, sounds almost startlingly real as he barks from my speakers. And somehow, I did not expect your resident "Cheapskate" to have such a rich voice. Has he ever worked as a radio announcer/personality?

As to the various microphones, not only was I astounded at the striking differences between them, I was equally surprised to discover how bad some were! Of course, I have not heard J. Gordon Holt in person; but I could tell that the Shure SM-57 and Crown PZM were especially poor. I thought that most of the others sounded reasonable, but I preferred a few especially: the Sennheiser MD-441, B&K 4006, MILAB LC25, and EAR The Mic particularly impressed me. I found the EAR microphone to suffer too much from a rolled-off or shut-in top end; but it was otherwise at least as good as any of the others.

But my favorite—the one which nearly fooled me into thinking that I was listening to a live voice in the room, and not a recording--was the Neumann U67. It was perhaps just a bit forward-sounding; but otherwise it seemed to give me the closest peek at what JGH might sound like in person. Several microphones in the test (as a matter of fact, most of them) suffered from a squawky coloration, rather like a telephone, only to a slight degree. Only the MILAB, EAR, and the above-mentioned Neumann seemed free of it. It is that effect which immediately tells these ears that I am listening to a voice fed through a microphone, and not a live voice. My microphone preferences might also tell you something about the sound colorations in my stereo system...

On track 8, the change in absolute polarity appears to occur at 0:49 or 0:50. If I am correct, then the polarity would appear to be correct after the change. I thought that track 17, mastered with the Sony PCM-1630 ADC, was a bit "pinched" compared to track 16, mastered with the Chesky 128x-sampling ADC, and that the "stereo spread" was more restricted. But there was not a dramatic difference. Track 18, where the different ADCs are interspersed, was tougher to track, and I have no idea if I heard correctly or not. When I closed my eyes it was easier to hear minute differences; however, watching the time-counter on the CD player tended to distract me and make the job more difficult. Here, then, is what I thought I heard, more or less:

0:11: 128x to Sony
0:34: Sony to 128x
0:44: 128x to Sony
0:56: Sony to 128x
1:08: 128x to Sony
1:26: Sony to 128x
1:40: 128x to Sony
2:23: Sony to 128x
2:34: 128x to Sony
2:48: Sony to 128x

But I was not absolutely certain of it all, to say the least! I also thought I could hear changes at 0:26 and 3:45; however, going back to tracks 16 and 17 to compare only confused me. I am curious, however: did I get any of them right?—Harrison Pierce Reed III, Gloversville, NY

The background noise on some of the tracks is actually microphone hiss or pipe organ wind noise, Mr. Dudley, not analog tape hiss. Yes, Mr. Reed, Sam Tellig worked his way through college as a radio announcer. And for those who have tried to detect the differences in absolute polarity and the A/D converters used on our first Test CD, the absolute polarity inverts at 1:38 in track 8, the Ravel Chanson, though I have no idea which way 'round is correct. (The cynic would say that which the listener prefers, of course; I prefer the second half of the song.) The times where RH and I edited from one transfer to the other in track 18, Schumann's Third Op.94 Romance (all musically natural break points) are:

0:08: 128x to Sony, bar 2, final 8th note
0:19: Sony to 128x, bar 6, first note
0:36: 128x to Sony, bar 12, final 8th note
1:01: Sony to 128x, bar 20, final 8th note
1:22: 128x to Sony, bar 27, final 8th note
1:44: Sony to 128x, bar 34, final 8th note
2:06: 128x to Sony, bar 41, final 8th note
2:50: Sony to 128x, bar 55, final 8th note
3:29: 128x to Sony, bar 67, final 8th note

Mr. Reed therefore only correctly identified one change, that from the Chesky converter to the Sony at 2:50, although he got close to correct times and correct identifications of the direction of the ADC change in the first minute or so. Before you all leap to your feet to guffaw, one of the reasons I put this A/B track on the first CD, as well as the complete piece transferred with both converters, was to demonstrate how hard such an A/B test is.

As Mr. Reed points out, the difference is not dramatic; when you have to do another task at the same time—such as watch the CD elapsed-time indicator—it becomes almost impossible. I hope many readers did try this test, but my congratulations to Mr. Reed for having the "sand" (as we say in England) for being one of only two readers actually to send in his attempt for publication, the other being Mr. Bernard A. Engholm of Carlsbad, California.JA

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