[LAU] [Sort of OT] Ringing in filters

[Folderol]

On Tue, 18 May 2010 22:56:44 +0200
Fons Adriaensen <fons at kokkinizita.net> wrote:

> On Mon, May 17, 2010 at 02:29:01AM -0700, Ken Restivo wrote:
> 
> > Well, Fons kind of sniffed at Jamin-- "you are mastering through a vocoder"
> 
> Well, that is not really what I wrote:
> 
> Responding to:
> 
> >> I was thinking about tearing into the code for
> >> something like Jamin to look at what's done there. Maybe there are
> >> better examples for me to use though?
> 
> I wrote:
> 
> > Jamin's FFT based filter is not really a filter, it's a vocoder
> > being used as a filter and it has side effects. 
> 
> Which is just true. It's also true that changing the window
> function and increasing the FFT overlap has reduced the
> artefacts to below -80..-90 dB w.r.t. the signal. But that's
> not a solution but a cover-up, coming at the expense of a lot
> of wasted CPU load - Jamin takes 35% on my 2GHz P4. For what
> it is doing 5% would be reasonable. And it doesn't help to
> bypass the EQ: it is *always* in circuit, even if the response
> is forced to flat when you enable the 'bypass' checkbox. Nor
> does it help to improve the atrocious type of responses that
> the 'HD' filter will generate if you are just a bit unlucky. 
> 
> Ciao,


This is rather disturbing. I had noticed that jamin was quite
processor heavy, but was unaware that this was unnecessary. Has this
been discussed with the devs? Mostly I like the way it sounds and works,
and the interface it presents (not that I have much to compare it
with). I would rather see it improved than dropped.

-- 
Will J Godfrey
http://www.musically.me.uk
Say you have a poem and I have a tune.
Exchange them and we can both have a poem, a tune, and a song.