On December 31, 2012 03:39:45 PM Charles Henry wrote: On Mon, Dec 31, 2012 at 3:17 PM, Neil <djdualcore@xxxxxxxxx> wrote: > On Mon, Dec 31, 2012 at 2:57 PM, Charles Henry <czhenry@xxxxxxxxx> wrote: > > At the ends of the frequency range, the group delay becomes significant and > > shifts some components of the signal more than others. > > > So, the wider the band, the less likely you are to hear the shifted > parts of the signal? > > > > Yes, in general. > > In the case we're describing, the top end of the passband is outside the range of hearing. The phase shifts might still be audible at the low end of the transducer's range. > > However, phase shifts aren't much of a problem by themselves--they're all over the place in any typical multi-driver system and placement in the room matters just as much. The loudspeaker crossover introduces the same effect. > > > Subwoofers are much more prone to phase shift problems. You notice it a lot when the bass seems to lag behind the beat--and this results from not having a continuous frequency response that goes down to 0 Hz (the ideal case) or bad resonance characteristics. > > > Really clean sounds have a lot to do with the tightness of the temporal response--but there are of course tradeoffs in any kind of design choice like these. > > > > Chuck > > Gabba gabba hey! Caught you off guard, eh? My my what a long thread... Happy new year y'all. Just an offside comment and question: I've repaired a lot of subwoofers. After repair we had to let them run by themselves with audio. I noticed a very strange phenomenon with all of them. When you listen to a subwoofer all by itself, the music which comes out of it seems to be noticeably off-key, until you turn up the rest of the audio system. For example, take oh, say the bass guitar in Ozzy's "Crazy Train". The bass would sound like it's playing in say G rather than F#. Then I would turn up the rest of the system, and all of a sudden everything sounded correct. At first I thought it was my proximity to the sub, or some kind of atmospheric effect similar to helium and the human voice. But it's weird that the effect instantly disappears when you turn up the rest of the system. Has anyone else ever noticed this? Cheers. Tim. Of the MusE project. _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
