ccrome2;468035 Wrote: > Thanks for the correct spelling. I found this > http://www.aes.org/e-lib/browse.cfm?elib=13285 (from Wolfson), among > other links. > > However, now that I re-read your original post, I see that you want to > reduce the pre-echo artifacts on 44.1 recordings. I'm not sure that's > possible. It's a little like removing echo from a recording -- you need > to know the impulse response you're trying to remove before can get > anywhere. Surely, and 44.1 recording you have has *many* impulse > responses, one for each microphone, recording track, processing step. > There's no way to fix that. > > -Caleb
In a modern recording studio all the mixing and mastering is done at a much higher sample rate relative to the 44.1kHz format of the release media (CDDA). Of course every D/A converter used to digitize a channel will have its bandwidth limitation to satisfy Nyquist for the sample rate used, but hopefully the sampling rate used will be high enough that the impulse response pre- and post-echos will be short. What I think could be worth addressing is the filter used in the final down-sampling to 44.1kHz in the mastering process. By having the Apodizing filter cut off a bit early it should be able to attenuate the pre- and post-echo tails (I guess this is the part where the feet get cut off causing the term Apodizing to be coined). It is also important that the upsampling filter should not add to the pre-echo, and should have should have a relatively short post-echo itself, hence the use of a Minimum Phase filter with a somewhat relaxed transfer function proposed here. -- dsdreamer ---------------------- "Dreamer, easy in the chair that really fits you..." ------------------------------------------------------------------------ dsdreamer's Profile: http://forums.slimdevices.com/member.php?userid=12588 View this thread: http://forums.slimdevices.com/showthread.php?t=69145 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/audiophiles
