Mike Rivers wrote:

Bob Cain writes:


a Sony ECM-MS907


Hey, that's a great little mic if it is properly
compensated. I did anechoic impulse response measurements
on it to calculate appropriate compensating FIR's (magnitude
and phase) and the little thing became a monster. I'd use
it for damn near anything.


But does it SOUND good? It's been quite some time since I tried a Sony
single point stereo mic, but the one I tried (ECM-909 or something
like that, but then they're all something like that) sounded pretty
plastic, kind of like what electrets used to sound like when we could
only afford them but would really have preferred something else.

Yeah, it sounds great after I convolve the compensating
FIR's I calculate from measurements with the recordings.
The frequency magnitude response can be made very flat and
the group delay very coherent. It's self noise is low
enough to be generally useful and there's no distortion I
can hear even in pretty high SPL live situations. I've not
stuffed one down the throat of a sax yet but with a sax
distortion would be pretty hard to hear anyway. :-)

I've done enough experimenting with these measurement and
computational techniques that the time coherence in a stereo
mic is something that really stands out for me now. After
this kind of compensation, things are precisely located
rather than somewhere out there in the general direction
of... Of course, the absolute accuracy of any stereo image
depends on the overall directional nature of the
configuration but the relative location of anything within
that, perhaps warped, space is heard with less spatial smear
after compensation.

Something that makes a big difference with that mic is to
remove the two screws holding the outer, protective shroud
and sliding it off to more expose the capsules when in use.
With it in place, there is so much HF dispersion that the
time compensation is not nearly as effective. Even without
compensation, the HF response of the mic is improved
considerably by removal of that shroud.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein