On Wed, Oct 19, 2011 at 10:37 AM, Fons Adriaensen <fons@xxxxxxxxxxxxxx> wrote: > The two issues are related. The FFT based EQ in Jamin uses a form > of block processing that leads to a filter that is not time-invariant, > it produces AM on some frequencies. In the first release that was very > obvious, you could actually hear it quite easily. Instead of changing > the algorthm to a correct one (which would be quite similar) the Jamin > devs chose to mitigate the effect by increasing the overlap between > successive blocks. IIRC there are now 32 overlapping blocks at any > time. This reduces the modulation to acceptable levels, but is also > what is responsible for the high CPU load. A correct implementation of > this type of EQ requires an overlap of half the FFT size, so it would > require much less CPU. My main concern with Jamin these days is whether or not it's being actively developed and/or supported... it hasn't been updated in quite a while (0.95 came out in 2005, right?). -- Brett W. McCoy -- http://www.electricminstrel.com ------------------------------------------------------------------------ "In the rhythm of music a secret is hidden; If I were to divulge it, it would overturn the world." -- Jelaleddin Rumi _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
