[linux-audio-dev] [ann] guitar preamp plugin, v2

[Tim Goetze]

Florian Schmidt wrote:

>On Thu, 30 Oct 2003 11:39:09 +0100 (CET)
>Tim Goetze <tim at quitte.de> wrote:
>
>> hi all,
>> 
>> a new, completely redone version of my valve-inspired preamp plugin is
>> up. improvements over the predecessor include:
>> 
>> * smoother distortion; clipping kicks in veeery gently
>
>vvvvvery nice.. Are you artificially limiting the amount of
>available distortion? it could even be more for certain things ;)  

yes, the gain is arbitrarily limited. you can simply adjust the port's
upper bound in preamp.cc for more. another idea would be to scale
before taking exp2() when setting up the sample loop; the curve could
indeed do with a little more steepness. in this case, fader
adjustments won't suffer as much from coarseness as they do when
increasing the upper bound. tell me what worked for you, i'm inclined
to implement the scaling method one of these days.

>I also very much like the crunchy sounds with just a bit of
>distortion. Maybe it would be nice to have the frequency shelving
>adjustable..

the frequency response is mostly due to the oversampling filters;
unfortunately i am at a loss for good realtime-compatible design
methods for those. it would well be possible to recalculate them
(chebyshev prototypes) but that would take quite a few cycles, and
knowledge about how to move the ripple/s in a chebyshev design
(anyone?).

post- (and maybe pre-) EQ is probably more fruitful (steve's set has a
3-way parametric + shelving iirc, i don't use EQ myself). i admit for
a complete 'preamp' there should be EQ. otoh i haven't found a good
reason to include it if there already are plugins out there that do it
as well :)

glad you like it,

tim