I am Paul, the author of an opensource (GPL) software synthesizer for Linux and Windows (it's at: http://zynaddsubfx.sourceforge.net). I am writing this mail to you because I have seen your program (Mammuth) and the way how it process the sound, by using long-term ffts.
I made a synthesis tehnique, that use longterm ffts (no windows) and is very intuitive, even for a musician. I implemented this ideea into my softsynth (as the "PADsynth" module) and it produces very good result and the ideea itself is very simple. To understand this and to use this intuitively, is very recomanded to read what I consider the "bandwidth of each harmonic" at http://www.kvraudio.com/forum/viewtopic.php?t=74129 . The base ideea of the bandwidth of each harmonic is that the harmonics of the sounds have larger bandwidths on higher frequencies. This happens in choirs, in detuned instruments, in vibratto,etc ; some ways to obtain the bandwidth are well known (but there are other ;-) ). Now, if I am considering the bandwith of each harmonic when I am using long term FFT synthesis, I will get a very beautiful sound and I can manage easily how is the enseble effect of the instrument. So the algorithm is very simple: 1) generate a long real array that contains the amplitude of the frequencies (it's graph looks like this http://zynaddsubfx.sourceforge.net/doc/paul1.png ) 2) convert this array to complex, by considering the phases random (this is the key: that phases are random) 3) do a long-term IFFT of the complex array 4) will result a perfectly looped sound that can be played at several pitches 5) enjoy of this beautifull sound obtained ;) As you see, this is very intuitively (even from musical perspective). Of course I made some variations of how I generate the array and I can make even non-musical sounds like noises, or metallic sounds. This is implemented in ZynAddSubFX and, because it's open source software, it can be studied (look in the src/Params/PADnoteParameters.C from the source code tree). Paul __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
