Q. Can measurement mics be used for recording music?

By Hugh Robjohns

Earthworks' omnidirectional QTC1 mic might look like one of the company's measurement mics, but it produces excellent results in the studio.

Can you tell me if it's common practice to use measurement microphones for recording? I have access to a good selection of measurement mics, and on paper they all have much flatter frequency responses than conventional 'recording' mics. So would they be a better choice when trying to record something without colouring the sound?

SOS Forum Post

Technical Editor Hugh Robjohns replies: Measurement mics are not often used in music recording for a number of reasons. When selecting the right microphone for the job, there are many more factors to consider than frequency response alone. In this case I'd suggest that polar pattern and self-noise are likely to be critical areas.

Measurement mics are almost always omnidirectional, which limits their practical miking applications somewhat. Spaced omni mics can sound great in a simple stereo recording, but close miking with omnidirectional mics never really works.

For a variety of technical reasons, measurement mics also tend to have very small-diameter capsules (typically 12mm or less) which means they are inherently noisier than the small (around 16mm) and large (around 25mm) capsules more commonly used in music recording mics. In general terms, the electronics of measurement mics tend not to be particularly quiet, either, because low noise isn't usually a requirement in measurement applications — it is far more common to want to know how loud something is than how quiet!

Having said all that, despite being designed with a different purpose in mind, some measurement mics can actually muster a performance which is equal to or even exceeds some high-end studio mics — but this is rare.

Published December 2004