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sambean ·
Hi Peeps!
Just been working on a fractional delay module using first order interpolation (from JOS' website), though some of you may find it useful..
Here's an example of it inside the karplus-strong example (making it in-tune)
http://freespace.virgin.net/cc.lai/Frac ... rplus6.osm
may be useful for chorus, pitchshifter, physical modelling etc..
Have fun
sam
edit [module input name changed freq -> delay] edit [frac = 0 error fixed]
Shifrin ·
Cheers Sam 🙂
Shif.
rl ·
neat stuff Sam.
.. there seems to be a little bug:
... f = rndint(freq); frac = freq - f; frac = 0; ...
so frac is always 0.
sambean ·
🙂
just keeping you on your toes...
Anyway, fixed now
Cheers rl!
sambean ·
Hi again,
Just realised some of the maths I used for this is wrong! So it's not doing what it says...
It's on the right tracks I think, but I'm not calculating the coef properly in the allpass section
I also have some doubts about rndint(x), does it round down, or to the nearest?
I'll leave the link if anyone feels the desire to muck about (it's based on the fractional delays from jos' website)
I'll update any progress,
sorry peeps,
Sam
Shifrin ·
sambean wrote: I also have some doubts about rndint(x), does it round down, or to the nearest?
It truncates, i.e. rounds down to the nearest integer (afaik!) - so if you want it to round to nearest integer add 0.5 to the integer you're rounding (which I assume you know anways!) 🙂
Shif.
sambean ·
Ta Shif,
Hehe, didn't think of the easy way!
Was using comparisons and subractions..
Gonna see if I can get it working to-nite, also working on a delay line pitchshifter..
keep y'all posted
sambean ·
Got it working now..
It's only working on linear interpolation at the mo, so some fractional notes sound a little bit muted, this should hopefully be sorted soon
Just to highlight the effect, I've added a tremolo control which modulates the delay length slightly
http://freespace.virgin.net/cc.lai/Frac ... rplus6.osm
sam
sambean ·
only me!
Changed the delay again,...
Fixed the glitchyness, it now sounds smooth and can handle pretty heavy modulation
http://freespace.virgin.net/cc.lai/Frac ... rplus6.osm
going to have a shot at that SSE chrous now..
g'nite
sambean ·
Well here's the first stages of an SSE chorus..
the delay modulation has'nt been calibrated, I've not read up on it yet, but you get the idea, a 4 voice chorus, 2 voices left + right using SSE poly delay..
easily expandable into more voices, different modulation, etc, etc..
http://rapidshare.de/files/3219203/Chorus.osm.html
hope it's useful
Sam
Shifrin ·
Tried to d/l the updates you posted but having some trouble, will try again tomorrow 😉
Cheers,
Shif.
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