[linux-audio-user] Re: professional audio measurement with linux???

[Phil Mendelsohn]

> From: sonicx <sonicx_ at 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