From: sonicx <sonicx_(a)gmx.net>
i was wondering if it is possible,and usuable, to make
precise pressure
and frequency messurements using linux. ie. to test high-end speakers.i
somehow guess so,but what do i need? can i use my
mic+soundcard+alsa+somemeasurementproggi ?
This sort of measurement is as much of an art as a science; if I were you
and wanted to get pretty serious about it, I'd look into measurement mics
before I got too hung up on the software. Earthworks M30BX is about $900,
but there are some less expensive solutions. A Shure SM-81, while not
strictly a measurement mic, will work pretty well in lots of cases. I
haven't seen them used for much less that $400 lately. :(
You want the measurement mic to be the best thing in the chain -- a good
mic on a cheap soundcard is better than a great soundcard with a poor mic.
As to software, I don't know about preset solutions -- sorry. If you
really want to get into it, fftw, gnuplot, and octave are all tools for
rolling your own -- and it's a great way to really learn what you're
doing.
But be careful -- when your ears and your measurements disagree, go with
your ears.
Phil Mendelsohn
(former mastering engineer, AES member, and audio boffin.)
--
Dept. of Mathematics, 342 Machray Hall
U. of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2
Office: 446 Machray Hall, 204-474-6470
http://www.rephil.org/ phil at rephil dot org