pfarrell;396922 Wrote: > Phil Leigh wrote: > > Pat - I mean discernible using the software+ears > > The software uses your soundcard to capture 2 versions of a > line-level > > signal and then aligns them precisely in time + level and lets you > hear > > the difference (or not) between them. > > Ah ha. Or you could use the old record two tracks, invert one, and > play > the sum. If its zero, there was no difference. > > If the result is all zeros, then there is no difference. Period, no > need > to waffle with "discernible" > > And if the difference is -100 dB down, its zero to me, even if its > numerically not zero > > For the math inclined, we could calculate an autocorrelation between > the > two signals, it automatically adjusts for slight delays > > But then I'm an engineer. And an audiophile. > > -- > Pat Farrell > http://www.pfarrell.com/
Pat, The "numerically zero" part works only in the digital domain. Once in analogue world we have the noise floor of the source and soundcard to contend with... plus the tiny drifting of the source sample clock... The software does a very sophisticated job of aligning the two signals in time, minimising any false "nulls". The software tells you in dB how far down in the mix any difference is. Listening to the difference - boosted by 60dB so you can actually hear it! - is interesting. Sometimes its just white noise - sometimes you can hear remnants of the music + noise... -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal... SB3 wired + Stontronics PSU - TACT 2.2X (Linear PSU) + Good Vibrations S/W - Altmann JISCO - MF Triplethreat(Audiocom full mods)- Linn 5103 - Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Townsend Supertweeters, Blue Jeans,Kimber & Chord cables Outdoors: Boom ------------------------------------------------------------------------ Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=60041 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/audiophiles
