Sendt: 16 Maj 2009 kl. 22:59 | IP-adresse registreret
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In the 1970's Hafler promoted "passive pseudo-quadraphonics", an inexpensive method of recreating ambient sounds at the rear from ordinary stereophonic recordings. Known as the "Hafler hookup", this consisted of two similar additional rear speakers, connected in series (typically 8 + 8 or 16 ohms total) between the live feeds to the front speakers. The crosstalk or loss of stereo separation in the front speakers was generally less than 2 dB while the rear sound level in a typical recorded live performance was about 7 dB below the front, but clearly audible. This passive method was almost as good as any of the matrix decoders which attempted to reconstruct a surround sound field from a two channel recording. It has been observed that ambient sounds in a concert, such as applause or coughs from the audience, are generally received in a non-correlated phase by the stereophonic microphones, while sounds from the musicians are generally in a more or less synchronous phase. Thus, if rear speakers are fed with the difference between the stereo channels, audience noises and echoes from the auditorium can be heard from behind the listener. __________________ mvh sund,
Kun de der har noget at skjule ønsker begrænsninger.
De, der siger det er umuligt, skal ikke forstyrre dem der er igang med det.
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I'm only in it for the music.
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