[music-dsp] R: R: R: Trapezoidal integrated optimised SVF v2

2013-11-10 Thread Marco Lo Monaco
Hi Andrew, you misinterpreted my words :) I know you are not intentionally hiding anything. The computation are intrinsically hidden themselves because of the nature of your approach (solving directly the differential eqs instead using the ABCD matrixes). All the coeffs involved in input, output

[music-dsp] Analog versus digital systems

2013-11-10 Thread Theo Verelst
Hi all, Of course I'm aware of it this work probably won't give m a (bit late) YUP existence in SanFrancisco or a well paid Berkeley professorship that I like, but at least I don't really run the risk of looking like a dumb-*ss when playing the unpaid professor a bit in this territory, and

Re: [music-dsp] R: R: Trapezoidal integrated optimised SVF v2

2013-11-10 Thread douglas repetto
Urs, I don't know if you're referring to music-dsp here, but this list is specifically not meant to be in the academic realm, but rather a place where people of all sorts with an interest in music and digital signal processing can chat. So I encourage you to share your results here! I'm

Re: [music-dsp] Analog versus digital systems

2013-11-10 Thread douglas repetto
Theo, please stop with the insults. On 11/10/13 9:55 AM, Theo Verelst wrote: Of course I'm aware of it this work probably won't give m a (bit late) YUP existence in SanFrancisco or a well paid Berkeley professorship that I like, but at least I don't really run the risk of looking like a

Re: [music-dsp] Trapezoidal integrated optimised SVF v2

2013-11-10 Thread Urs Heckmann
On 09.11.2013, at 01:57, Tom Duffy tdu...@tascam.com wrote: To paraphrase, all are good enough if the frequency is low ( pi/3); Simpsons is the best, but blows up above 0.8 pi Note that Andys approach uses trapezoidal integrators just as that - integrators. While the whole structure of the

Re: [music-dsp] Trapezoidal integrated optimised SVF v2

2013-11-10 Thread Urs Heckmann
Hi Douglas, No worries, I couldn't have started my business without this list, it was an important factor in my career - for the very reason that it isn't strictly academic. I would love to give back if it's of anybody's help. (if we ever find the time to write that damn paper ;-) Thanks, -

Re: [music-dsp] Time Varying BIBO Stability Analysis of Trapezoidal integrated optimised SVF v2

2013-11-10 Thread Ross Bencina
With reference to my previous message: It looks like there is a change of basis matrix T that can be used to satisfy Laroche's Criterion 2 (time varying BIBO stability at full audio rate), at least for k 0. T: [ 0, 1] [ 1, -1/1 ] This matrix requires k 1/1 but it seems

Re: [music-dsp] Analog versus digital systems

2013-11-10 Thread Ezra Buchla
i don't want to feed the troll, but... a) of course we all know about the sampling theorem and sync interpolation. truly! b) though i enjoy reading ASM synth code, i don't see anything here that is interesting. what am i supposed to look at? a character display? a phasor? an in-place filter or

Re: [music-dsp] Trapezoidal integrated optimised SVF v2

2013-11-10 Thread Ezra Buchla
as a longtime lurker, it's really nice to see this list heating up again, and to see mr. simper's comments finally make it through. cytomic is wonderful stuff and i for one certainly appreciate the sharing. there's a non-technical thread of discussion interleaved here, which is about education

Re: [music-dsp] Analog versus digital systems (Ezra Buchla)

2013-11-10 Thread Theo Verelst
... a) of course we all know about the sampling theorem and sync interpolation. truly! b) though i enjoy reading ASM synth code, i don't see anything here that is interesting. ... I'm sorry to say, but while of course I don't feel all too much of it, and of course that isn't a reason to use my

Re: [music-dsp] Analog versus digital systems (Ezra Buchla)

2013-11-10 Thread Ezra Buchla
i'm sorry mr. vereslt, i do apologize for insulting you. to be honest, i made a mistake with the e-mail and thought this was still under that other thread. and so i tried to read your code, [ which if course is very interesting and informative to me (since i am not nearly at your level as an

Re: [music-dsp] Analog versus digital systems (Ezra Buchla)

2013-11-10 Thread Ezra Buchla
or, oh! would you suggest that we stick to an analog design like the switched capacitors? but there are still lots of reasons to try and keep everything on DSP in terms of part count in a device. again, i think of this space as very informal discussion, s please no hard feelings, ezra b On Sun,

Re: [music-dsp] R: Trapezoidal integrated optimised SVF v2

2013-11-10 Thread robert bristow-johnson
On 11/8/13 5:20 PM, Andrew Simper wrote: On 8 November 2013 18:03, Marco Lo Monacomarco.lomon...@teletu.it wrote: ... What I would say more about this method is that , since it is intrinsicly a biquad, you not only have to prewarp the cutoff f0 but also the Q. In such Are you talking about

Re: [music-dsp] Trapezoidal integrated optimised SVF v2

2013-11-10 Thread robert bristow-johnson
On 11/8/13 6:47 PM, Andrew Simper wrote: On 9 November 2013 08:57, Tom Duffytdu...@tascam.com wrote: Having worked with Direct-Form I filters for half of my career, I've been glossing over this discussion as not relevant to me. It depends if you value numerical performance, cutoff accuracy,

Re: [music-dsp] Trapezoidal integrated optimised SVF v2

2013-11-10 Thread robert bristow-johnson
On 11/8/13 11:50 PM, David Reaves wrote: I think the distinction is that SCIENCE is open-minded. Scientists, OTOH, are only open-minded if they choose to be. But then, the closed-minded ones aren't really scientists, now are they? ;-) oh, c'mon. *anyone* can be close-minded. being skilled

Re: [music-dsp] R: R: Trapezoidal integrated optimised SVF v2

2013-11-10 Thread robert bristow-johnson
On 11/9/13 6:52 PM, Andrew Simper wrote: Marco writes: Well, of course the s = (T/2)(z-1)/(z+1) conversion comes from discretizing a differential equation. but remember, that's not the only way to convert s to z. that's the bilinear way to do it. ... What I would say more about this

Re: [music-dsp] R: R: Trapezoidal integrated optimised SVF v2

2013-11-10 Thread Urs Heckmann
On 11.11.2013, at 01:33, robert bristow-johnson r...@audioimagination.com wrote: but you cannot define your current output sample in terms of the current output sample. But that, with all due respect, is what has been done for quite a while. It isn't the major ingredient of great sound,

Re: [music-dsp] R: R: Trapezoidal integrated optimised SVF v2

2013-11-10 Thread robert bristow-johnson
On 11/10/13 5:12 PM, Urs Heckmann wrote: On 11.11.2013, at 01:33, robert bristow-johnsonr...@audioimagination.com wrote: but you cannot define your current output sample in terms of the current output sample. But that, with all due respect, is what has been done for quite a while. it's

Re: [music-dsp] R: R: Trapezoidal integrated optimised SVF v2

2013-11-10 Thread Ezra Buchla
i hope it's ok if i sum up the main themes here with background links, as i understand it. the thread is just such a mess... here is the state variable filter from hal chamberlin 1985 or so: http://t.co/SVJp7iAgqb pierre dutilleux wrote up a nice discretized and tuned version in dafx 1998:

Re: [music-dsp] R: R: Trapezoidal integrated optimised SVF v2

2013-11-10 Thread Ross Bencina
Hi Ezra, A few comments: On 11/11/2013 3:19 PM, Ezra Buchla wrote: there seems to be some concern about distortion introduced by the trapezoidal integration. i've tried the algo in both fixed 32 ands float, and it seems to sound and look ok to but i have not done a proper analysis either

Re: [music-dsp] R: R: Trapezoidal integrated optimised SVF v2

2013-11-10 Thread Ross Bencina
On 11/11/2013 12:21 PM, robert bristow-johnson wrote: but you cannot define your current output sample in terms of the current output sample. But that, with all due respect, is what has been done for quite a while. it's been reported or *reputed* to be done for quite a while. but when the