adamdea wrote: > John could you help me with what a complex and simple filter means. By a > simple filter do you mean something like a [rectangular?] windowed sinc > function? I have been trying to read up to see what the standard way of > designing filters was and have been pointed in the direction of the > Parks-McClellan filter design algorithm. Is that what you had in mind > as a complex filter?
A windowed sinc is a simple filter. A complex filter is made by running the data through one filter, then running through a different filter, then running it through yet another. Most of the ones I see in chips have at least three separate filters cascaded together. This cascading of different filter functions SEEMS to be what is causing the audible issues. It MAY be something else like not having enough bit depth to handle those different filter type or something else all together. This cascading of simple filters is not anything new, I've been reading up on some discussions about the very first digital filters used in CD players and they did exactly the same thing. It's a time honored tradition! John S. ------------------------------------------------------------------------ JohnSwenson's Profile: http://forums.slimdevices.com/member.php?userid=5974 View this thread: http://forums.slimdevices.com/showthread.php?t=97881 _______________________________________________ discuss mailing list discuss@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/discuss
