On Deciding Which Microphone To Buy

Note: Elsewhere in this issue, I’ve reported on a comparison test of eight different vocal microphones. I got a little ambitious with this test, and used a “blind” subjective listening panel to compare and rank the microphones. Because such tests are new to Home and Studio Recording, I felt it would be useful to discuss them, their background and their place in the Cosmos. I hope to continue using these test methods for future product evaluations for Home and Studio Recording. –Dave.

How do we really know what’s the best audio device? Who’s got the time, resources, connections, etc. to go out and actually test ‘n listen to every device, conclusively determining how it stacks up in the Cosmic Audio Device Sweepstakes? Not me. Probably nobody. Nonetheless, we need to know. None of us can afford to just keep buying all the different devices available until all our clients say, “There! That’s the one!”

The beginner’s way out of the dilemma is to just check out the spec sheets. Look at the response curves and pick the one that’s flattest. Or the one with the lowest noise, or highest distortion threshold, or most consistent polar plots. You makes your choice and you pays your money.

But if you’re like me, you wonder if you really made a good decision there.

Lack of knowledge leads to the process of using other people’s opinions, especially those of your peers and idols. This is a time-honored way of making decisions and so you read the trade mags. Who’s interviewed this month? What’d they use on their latest platinum record session? Such anecdotal stuff actually works, sort of. Unfortunately, it also congeals into mythology. This is why the manufacturers devote so much of their advertising budgets to product endorsements by Pros and Celebrities.

But this is all loose talk. What’s the real truth and how do you find it out? The answer is that you have to test, of course. But how? Do you simply replicate, at considerable expense, all the tests the manufacturers have conducted to see if they’re telling the truth? What else might you test for? What physical quantity could you select to represent the attribute “best?”

It turns out that the relationship between physical measurements and subjective qualities – “sounds cool,” for instance – is shaky. Correlations exist and you can make generalizations like “flatter is better” without getting into serious trouble. But you’d better remain skeptical. Just because we generalize that “flatter is better” doesn’t mean that “flattest is bestest.”

The best answer I know for this audio stuff is the subjective listening test. You listen to whatever devices you want to know about – passing music through them – and you make judgments about How They Sound.