[PD] rjdj, was : Re: [equalizer] / [lowshelf] / [highshelf] in purepd!

[cyrille henry]

hello

Frank Barknecht a écrit :
> Hallo,
> cyrille henry hat gesagt: // cyrille henry wrote:
> 
>> nice to see all of this good stuff in pure vanilla pd.
>>
>> i've got some questions : -why this is not available in pd-extended / in pd
>> svn?
> 
> The rjdj-svn is the canonical location for rj-lib, but of course as it's
> GPL/BSD it can be copied anywhere. For contributions we can only accept stuff
> that either is BSD or transfers copyright to Reality Jockey as we want to avoid
> legal problems as a distributor of rjlib to others ("others" currently includes
> Apple, so we have to be extra-extra cautious about this.) 
ok.

> 
>> -did you benchmark e_beequad~ regarding to bequad~ specially when cutoff /
>> band is change frequently)
> 
> Do you mean to "biquad~" or what is "bequad~"? biquad~ in Pd should be a lot
> faster, but I didn't benchmark it. 
yep, tipo, i mean biquad~.
of course biquad~ look faster, but i'm wondering how many times...
i'll have to look at performance when i'll have more time.
 
> 
>> -have you noticed that in svn/nusmuk/osc you can find lot's better bl saw
>> that you can use (ok, it use expr~, but you can easily remove it). this bl
>> oscillator use a personal enhancement of miller technique.
> 
> No, I hadn't seen this. It doesn't seem to need the [samphold~] which would be
> cool to avoid anyway. Could you elaborate the algorithm a bit and how it's
> better? 
it's sound lot's better!
isn't that the aim?
(i think it is almost perfect, and can easily be enhanced)
try to fft's it if you're not convinced.

i think  i would take me 1/2h to explain in french exactly what i made.
so i really can't explain it in a mail in english.

in miller algorythm, the quick transition of the saw is replaced with a softer transition.
this is fine.
but the switch from saw~ to the soft transition is causing problem.

in "my" algo the transition is based on sinus cardinal (is that the english name?) and last for a whole period of the waveform.

if you need more explanation, you'll have to ask some math geek. (mathieu maybe?)




> 
> I think, currently it's probably a bit slower because of the sin(), but maybe
> that could be put into a tabread~. 
i think the sin object is doing a linear interpolation in a 512 point table.
(don't know how it is done in expr~, but expr~ is not used for rjlib because of it's licence, right?)


Cyrille

> 
> Ciao