Eric Seaberg wrote: > I've been in the recording business for 36 years and have worked in some > of the most prestigious facilities in the World... what you're talking > about isn't really 'phase' as much as it is 'time-alignment'.
Yes. Even though every mic pre and/or console has a Phase button, that is not really what they are worrying about. > There are phase-reverse > switches on consoles ONLY to be used if an improperly wired cable > creeps into the session, or for an obvious effect. The one other obvious use is when you mic both the top and bottom of a single snare drum, you have to switch "phase" on one to keep them working properly. > Remember that sound travels typically at 1100 feet/second, and the > amount of phase shift from two summed mics being 30+ feet apart on the > same instrument will NEVER approach a complete 180-degree phase shift. Well, a bass guitar low E is about 41 hz, or 20 feet. You could in theory get them out of sync if you recorded in an anechoic chamber, but all real recording spaces are not anechoic. In more normal ranges, near middle-C (about 261 Hz) and up an octave or so, you get wavelengths of 2 feet or so, so it is likely that any two distant mics are out of polarity/phase as the notes go up and down. Which is why spaced omnis are out of favor, replaced by M+S, ORTF, etc. > Considering > most instruments don't have a fundamental frequency above 5kHz, your > concern is really minor. Having a mic out-of-phase with the rest of > the mics in the room will cause MUCH greater disasters!! Very true. Most people don't understand that 5kHz is really high frequency. Fundamental frequencies of the human voice, and guitars (which were designed to accompany the human voice long before anyone knew what frequencies were) range from 200 Hz to the high hundreds, say 800 Hz. A serious opera soprano can sing to "high C" or C6, about 1046.50 hZ Its the overtones that make instruments and singers identifiable, but there really isn't that much up about 8kHz. Just reverb, decay, and room resonances, which are what make music sound like music. Thiel, the ancient Dahlquist D10s, Quads, and many other speakers try to address the very important issue of relative phase coherency. Its all relative, and important. But I don't see any point in worrying about absolute phase/polarity. IMHO, YMMV, etc. -- Pat http://www.pfarrell.com/music/slimserver/slimsoftware.html _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/audiophiles
