On Tue, Sep 17, 2013 at 12:46:06PM +0200, Jörn Nettingsmeier wrote:
> On 09/17/2013 04:37 AM, Eric Wong wrote:
The primary tools to measure an A/D or D/A (that's what it amounts
to, the rest just be pretty transparent in any recorder) are jaaa
and jnoisemeter. Both were explicitly designed for the job.
> but all these measurements either rely on reference gear to produce
I you have a good quality audio card it is perfectly possible to
use this as a signal source. First measure it separately, so you
have an idea of the limits of what you can do using it. For some
measurements you also need to calibrate it using a true RMS audio
voltmeter which you can beg, steal or borrow.
You may need some simple HW: passive attenuators (three resistors),
and plugs or test cables to short-circuit inputs. For the rest you
need to perfectly understand *what* you try to measure, and have
a very systematic approach to doing it.
> there's an old saying in german which unfortunately doesn't
99% percent of false results are due tp lack of understanding, and
failing to verify basic things such as levels.
A world of exhaustive, reliable metadata would be an utopia.
It's also a pipe-dream, founded on self-delusion, nerd hubris
and hysterically inflated market opportunities. (Cory Doctorow)
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