krochat;478824 Wrote: > Phil, > > The definitive paper on this is > "Lipshitz, S. P., Pocock, M., and Vanderkooy, J., "On the Audibility of > Midrange Phase Distortion in Audio Systems," J. Audio Eng. Soc., vol. > 30, > pp. 580-595 (1982 Sep.)." > > I'm unable to find an online copy. They determined that absolute phase > was detectible at statistically significant levels under some > circumstances. > > You are correct that when multimiking or using phase-incoherent > speakers, there's not really any point. But when a single stereo > microphone pair is used with a phase coherent speaker (the researchers > used Quad 63's AFAIK) or headphones, changes in absolute phase can be > heard with some material. > > For Sine-wave like instruments (flute?), there's no difference. > Trumpets produce a highly asymmetric sound wave (see > http://www.audiomisc.co.uk/asymmetry/asym.html ) where changes in > absolute phase usually be detected at statistically significant levels. > > Try changing absolute phase with a Telarc recording of the Empire Brass > Quintet - my favorite is "Braggin' in Brass" ( see > http://www.empirebrass.com/cd-order.html ). Yes, I know Telarc uses 3 > microphones, but I still hear a difference when I switch polarity. > > Regards, > Kim
Kim, I'm familiar with this paper. It has issues (for me), one of which is that whilst they used speakers that are ostensibly dipole in nature they didn't repeat the test with the speakers physically turned through 180 degrees. This leaves open the possibility that there is an asymmetric component in the speaker reproduction that either emphasises or even creates the phase detection... Anyway, I will try and source that Telarc recoding you mention - thanks. -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal... SB Touch Beta (wired) - TACT 2.2X (Linear PSU) + Good Vibrations S/W - MF Triplethreat(Audiocom full mods) - Linn 5103 - Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Townsend Supertweeters, Blue Jeans Digital,Kimber Speaker & Chord Interconnect cables Kitchen Boom, Outdoors: SB Radio ------------------------------------------------------------------------ Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=69447 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
