Steve Harris wrote: >On Sun, Nov 02, 2003 at 10:49:17PM +0100, Tim Goetze wrote: >> the frequency response is mostly due to the oversampling filters; >> unfortunately i am at a loss for good realtime-compatible design >> methods for those. it would well be possible to recalculate them >> (chebyshev prototypes) but that would take quite a few cycles, and >> knowledge about how to move the ripple/s in a chebyshev design >> (anyone?). > >Have you tried polyphase filters? I've never used them but I've heard they >are good for oversampling.
i don't have any precise cycle-consumption figures (a good reason to try the polyphase filters one day) but i seem to remember having figured that they come at equal or bigger cost for comparable stopband attenuation. then, their peak at 2 - 3 kHz made me go with the current filters because it is a characteristic of the circuitry i investigated, and it comes for free. just seemed to fit so nicely, and i could use the tools i know best. though one day i'll try the polyphase design for some exact figures. >Nice plugin BTW, I've noot been able to play it myself (my guitars ill), >but the sample recording sounds great. thanks, it's lovely to hear that from 'Mr LADSPA'. :)) tim
