Hope this is OK to post here. If not, please let me know. I found the thread on binaural / simulated stereo post-processing interesting. Seems like an area worth exploring. Did some reading. Good search terms are "simulated stereo", "haas delay", and { stereo "comb filter" }. As seen above, the two main techniques seem to be: 1. Haas delay, in which the mono signal is split into two identical channels with a little bit of each signal subjected to delay and mixed to the opposite channel. This simulates sound from a wide source hitting two ears at slightly different times. There are several parameters that can be tuned, e.g. to shift sources left or right on the "soundstage". These might be used to shift interfering signals' apparent positions in audio space, especially if combined with some differential EQ to shift tones left or right depending on their pitch. 2. Complementary comb filtering in which the mono signal is split as above and then routed to two comb filters with the combs' bandpass centers offset in complementary fashion on the two output channels. (e.g. the left channel gets 64 Hz, 1 kHz and 4 kHz bandpass centers, while the right channel gets 32 Hz, 500 Hz, and 2kHz). I heard a monaural Horowitz piano track played through a complementary comb filter once and it made the piano sound like it was 30 feet wide. The effect was fascinating, but not neccessarily preferable to the original. Still, it might be useful for separating two distinct CW tones in a contest type situation. There's a cheap ($8) analog kit to do complementary comb filtering: http://store.qkits.com/moreinfo.cfm/fk651 Also there are complementary comb filter and Haas delay plugins for all the major Windows and Macintosh digital sound editing packages. Obviously this would be the way to go if you wanted to experiment. No connection with the above vendor, except ordering the kit today. 73, Ken K3VV Coopersburg, PA _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
In message <[hidden email]>, K. Rice
<[hidden email]> writes >2. Complementary comb filtering in which the mono signal is split as >above and then routed to two comb filters with the combs' bandpass >centers offset in complementary fashion on the two output channels. >(e.g. the left channel gets 64 Hz, 1 kHz and 4 kHz bandpass centers, >while the right channel gets 32 Hz, 500 Hz, and 2kHz). This should sound interesting with a CW signal. ISTM that as you tune through the signal it will hop between left and right ears several times :-) Should the split not be around a fixed frequency; say about 500Hz ? Trev G3ZYY -- Trevor Day UKSMG #217 www.uksmg.org _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Free forum by Nabble | Edit this page |