Condenser (electret?) Gnraliste, prvu as pubs AT plutt for piano and brass. I use it for voice (interviews).
It is powered either by battery (1xAA) by phantom (9-52V)
Note that the MicroTrack from M-Audio has a phantom power to the lame ATM31a no problem

OVERALL OPINION

I have for 5 years now, and I used regulirement it became the standard companion of all my recording.

as:
Finish
The lack of sensitivity to handling noise (perfect for the interview by hand)
The high level output
Sound a little hot

minimum:
quite sensitive to plosives
lack of lightweight DEFINITIONS

I have not tried other smodles for the type of use I have
The price quality ratio is very well
I would do without hsiter (or plutt if j'hsiterais between 31a and an AT897)