[LAU] Subject: Albums under a label recorded and/or mixed with Linux

fons at kokkinizita.net fons at kokkinizita.net
Sat Sep 25 17:48:15 UTC 2010


On Sat, Sep 25, 2010 at 10:07:46AM -0700, Patrick Shirkey wrote:

> To clarify further, are you referring to the entire ui or specifically to
> the parametric eq ui which Jan designed? I think Jan would be the first to
> admit that he is not a dsp expert but was instead attempting to provide a
> user friendly interface for the specific plugin.

The confusion continues :-)

AFAIK Jamin does not have a parametric EQ. It uses an FFT-based
method with a graphical interface that makes it look either like
a combination of 'freehand' frequency response and parametric,
or as a 30-band 'graphic EQ'. But it's the same algorithm in all
cases, and it's not a plugin.

If works by taking the FFT of the input, multiplying in the
frequency domain by some precomputed values, and transforming
back using an IFFT. This modifies the frequency response of
course, but it is *not* a linear filter and produces side
effects (modulation). Jamin minimises this by 1) windowing,
which amounts to crossfading between processed blocks of
samples, and 2) processing much more overlapping blocks than
the minimum required to do crossfading (which would be 2).

The proper way to implement a filter of this type (with a FR
defined at all multiples of Fsamp / 1024) would be by using
linear convolution rather than cyclic. But as said, this is
not the right kind of filter anyway.

Ciao,

-- 
FA

There are three of them, and Alleline.



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