12 Mar
2010
12 Mar
'10
8:42 a.m.
On Friday 12 March 2010 15:20:33 fons(a)kokkinizita.net wrote:
Do you want a logarithmic *scale* or a logarithmic
*analyser* ?
In other words what exactly are you trying to do ?
How accurately you can measure certain things (or if
they will be visible at all) depends on the analyser
bandwidth and the levell of its sidelobes. For Jaaa
the BW is constant over the F range, and all sidelobes
are below -80 dB (and decreasing as you move away from
the center frequency). For Japa BW is function of F and
sidelobes are below -40 dB.
The idea (under discussing at some of russian DIY audio forum) is to use
multitone signal, compare it before and after audio amplifier and (having such
*multiple* results for *different* amplifiers) to try get some - at least
partially useful - correlation between results and subjective audio
perceptions (in particular, "clearance" - don't know an appropriate English
term; it's about how easy different instruments can be "separated" in
brain).
I'm not sure it is a right way, but would like to take participation in the
experiment (especially with my last SE-invention :-)).
Fellows (using appropriate software analyzers under MS win) show very clear
spectrum plots for original multitone signal (ten -20db tones in 20Hz - 20KHz
range). Having single-boot Linux, I'd want to get something the same :-)
Andrew