"Use Alternate FFT" ?

[Doug]

I was changing my preferences the other day and I noticed a check box in the preferences window under the general tab titled "Use Alternate FFT".
It doesn't mention it in the user manual - what does checking this box do?

[Craig Maier]

The Diamond Cut System uses ffts to do some of its work. The original fft routine was written by Diamond Cut itself. It worked fine, but was not otimized for speed, especially with some Intel processors. So, we obtained an fft from Intel otpimized for the latest generation of their processors and certain things became faster like the CNF. But, some processors crashed with the Intel fft. So, if that happens, you can go back to the original fft that we wrote a long time ago which seems to be universally compatable with all processors made by all manufacturers.

So, in short, the alternate fft is the one that we wrote a long time ago which is universally stable, but slower than the newer one.

[Doug]

ok, I had no idea about this. Does changing it impact on digital artifacts etc or sound quality in any way that you know of?

[Craig Maier]

No impact. The mathematical results producted by the original fft and the faster fft are precisely the same.

Craig

[Marc Hildebrant]

FFT From Intel

Craig,

I didn't know that Intel provides FFT's for their CPU's (I'm not much of a software person). Is the Intel software a "C" subroutine?

Regards,
Marc

[Craig Maier]

As I recall, it is an fft routine that Intel optimized for their processors and is written at the machine assembly level. The Diamond Cut (or Alternate fft) is written in C.

[Marc Hildebrant]

O.K. then, thanks Craig.

Regards,
Marc