A Moment of Truth and Epiphany

I will tell you straight out, I learned more about loudspeakers, listening and subjective measurement in one day of blind testing under Floyd’s kind and gracious supervision than I had in the previous decade! What was particularly interesting was that three of us, three-out-of-four partners in a fledgling little loudspeaker company, served as our own highly biased listening panel. We knew, before we even started, that our loudspeakers were superior. We had no doubts. So, we settled down to listen to our babies behind the black screens. We told ourselves. We filled out our test forms. We described quite convincingly to ourselves exactly in what ways and how it was that our babies, our lovely-looking cherry veneer ready-for-prime-time loudspeakers, sucked.

We told ourselves what was wrong, in comparison with a whole bunch of speakers, with our babies, our beloved prime-time babies. It was traumatic. It was an education. Nobody from NRC came into the room and said, “I’m sorry, Mr. Moulton. Your speakers didn’t make the grade.” I wouldn’t have believed them if they had. But I did it. It was me that said, “Hey, self! Your speakers aren’t competitive. Whaddaya think of them apples, eh?” And my partners all agreed. It wasn’t just me. When our speakers were named Speaker D, Speaker D just wasn’t very good. When they changed the name of our speakers to Speaker B, and located them elsewhere in the room (still behind the screen, of course), well, it was Speaker B that came up short.

What I learned that day was that blind subjective testing is a powerful, effective tool, a tool that cuts through the bullshit and wishful thinking very, very quickly and very, very effectively. And it’s important to keep in mind that, while we didn’t get the answers we either wanted or expected, we saved ourselves tens of thousands of dollars that day, maybe hundreds of thousands of dollars. It was an absurdly cheap lesson, however much it hurt!

Subjective Testing in Audio Classes

So, I returned to Berklee to continue my years of servitude. One of the things I did, inspired as I was by the effectiveness of that blind listening lesson, was to introduce my students to the virtues of blind testing of loudspeakers. Our tests weren’t very rigorous, but they sure were great teaching moments.

We’d set up four speakers on a table underneath a concealing layer of grill cloth, and I’d ask the class to rank the four speakers on a scale of 0 to 10, where 0 represented truly ugly reproduction, so ugly you couldn’t stand it, and 10 represented perfect reproduction, so good you couldn’t tell whether it was a loudspeaker or the source sound. We’d play four different recordings (one of them was pink noise) and have each student rank each speaker for each recording.

In one class, I remember that after the tests were over, and we had pulled off the grill cloth, one student exclaimed, “Oh, man! I can’t believe I have such terrible ears! I really down-rated B (a famous, highly regarded brand), while everybody knows it’s a great speaker!”

What a great example of group-think! What a clear example of brand prejudice! The student would prefer to choose speakers based on what his colleagues and trade-mag ads told him to choosing with his ears! And he blamed his ears for not going along with the party line!! He never even considered the possibility that maybe, just maybe, his ears were right!!!

We spent close to an hour that day discussing the implications of not using our ears, of relying on group-think and brand prejudice instead. We listened to the speakers again, while we could see them, to see if they still sounded the same (they did, sort of).

I did this sort of exercise for every class I taught, and I kept it up when I subsequently taught acoustics at UMass Lowell. And when I became a consultant again, I began to do it for money, having listening panels evaluate devices for manufacturers. Devices included loudspeakers, microphones, speaker cables and CODECs.

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