KVR Audio

Z1202 · Post by **Z1202** » Tue May 22, 2012 8:26 am

Hi all

[Edit: Nov 27, 2018 added link to ADC2018 presentation]

Here it is: The Art of VA Filter Design. It is based around the TPT (a.k.a. zero-delay feedback) filter design method. No preliminary filter design knowledge required.

Mirror:
https://www.discodsp.net/VAFilterDesign_2.1.2.pdf

Older revisions:
http://www.native-instruments.com/filea ... _1.1.1.pdf (NI website)
http://www.discodsp.net/VAFilterDesign_1.1.1.pdf (thanks to george for mirroring)

The book has been actually written in the last week of April, but there were some unforseen delays getting it published. In the meantime I replaced the originally used DF2 integrators with TDF2 integrators (thanks to mystran

). It's remarkable how at the very same time the same topic got extensively discussed on KVR

The book text hasn't been extensively proofread, so if you spot any mistakes, the feedback is welcome. Equally, I would appreciate the mirroring of the file, in which case please drop me a note, so that I can inform you of the updates.

The ADC2018 presentation of the 2nd revision of the book is here https://www.youtube.com/watch?v=zPzCLqkQnr0

Enjoy!

Regards,
Vadim

mystran · Post by **mystran** » Tue May 22, 2012 8:30 am

Your diode approach is interesting.

Specifically what I mean the signal flow graph of Figure 4.13; I never thought about it that way, even if I've written a derivation for the analog model here at some point (and at that point I remember noting that "this gives the same results as Stinchcombe" so it's not like I was the first one).

Your linear solution looks pretty much exactly as awful as mine.

Anyway, lots of useful content in there. Certainly explained very well and at least for me it looks like it should be reasonable easy to understand.

mystran · Post by **mystran** » Tue May 22, 2012 8:52 am

Z1202 wrote: The book has been actually written in the last week of April, but there were some unforseen delays getting it published. In the meantime I replaced the originally used DF2 integrators with TDF2 integrators (thanks to mystran ).

Oh, don't thank me. Thank neotec whose idea it was. I just stole it from him.

Z1202 · Post by **Z1202** » Tue May 22, 2012 8:57 am

mystran wrote:
Z1202 wrote: The book has been actually written in the last week of April, but there were some unforseen delays getting it published. In the meantime I replaced the originally used DF2 integrators with TDF2 integrators (thanks to mystran ).
Oh, don't thank me. Thank neotec whose idea it was. I just stole it from him.

But it was you who drew my attention to that subject. Probably I should credit neotec too (do you happen to know his actual name?)

discoDSP · Post by **discoDSP** » Tue May 22, 2012 9:12 am

As requested I have mirrored the PDF at http://www.discodsp.net/VAFilterDesign.pdf

antto · Post by **antto** » Tue May 22, 2012 9:15 am

No preliminary filter design knowledge required.

are you saying that there is even a small chance that i might understand something if i attempt to read this?

discoDSP · Post by **discoDSP** » Tue May 22, 2012 9:19 am

antto wrote:are you saying that there is even a small chance that i might understand something if i attempt to read this?

the book wrote:The prerequisites for the reader include familiarity with the basic DSP concepts, complex algebra and the basic ideas of mathematical analysis.

antto · Post by **antto** » Tue May 22, 2012 9:20 am

then nope..

mystran · Post by **mystran** » Tue May 22, 2012 9:32 am

Z1202 wrote:
mystran wrote:
Z1202 wrote: The book has been actually written in the last week of April, but there were some unforseen delays getting it published. In the meantime I replaced the originally used DF2 integrators with TDF2 integrators (thanks to mystran ).
Oh, don't thank me. Thank neotec whose idea it was. I just stole it from him.
But it was you who drew my attention to that subject. Probably I should credit neotec too (do you happen to know his actual name?)

No, I was wondering about it in "my own" thread.

mystran · Post by **mystran** » Tue May 22, 2012 9:35 am

george wrote:
antto wrote:are you saying that there is even a small chance that i might understand something if i attempt to read this?

the book wrote:The prerequisites for the reader include familiarity with the basic DSP concepts, complex algebra and the basic ideas of mathematical analysis.

From quickly glancing through the text, I don't think that's as bad as it sounds. He explains everything he does quite clearly. So I think there's a chance that anyone that can write code can probably figure it out. In fact, it looks like it's easier to read than most books on traditional digital filters.

jupiter8 · Post by **jupiter8** » Tue May 22, 2012 9:49 am

antto wrote: then nope..

Just in case you didn't know,Complex Algebra doesn't mean "really really hard" Algebra,it just means Algebra with complex numbers which isn't that hard if i recall correctly (been a few years since i read it). I've yet to discover what you use it for and what it got to do with audio but i'm sure someone will tell me.

Urs · Post by **Urs** » Tue May 22, 2012 9:52 am

Looks very cool - many thanks for sharing! When did you have the time to write all this

thevinn · Post by **thevinn** » Tue May 22, 2012 9:53 am

NICE BOOK!

Thanks for adding this to the body of DSP literature!!!!

Ichad.c · Post by **Ichad.c** » Tue May 22, 2012 10:35 am

antto wrote: then nope..

Hey Annto, I agree. Personally I've learn't more about filters by practical examples and comments by mystran and neotec and andy_fx, than I did reading that pdf. That being said though; I'm glad I read it - because the 30% that I understood was quite enlighting. Just looking at that diode-ladder block diagram makes me

mystran wrote: In fact, it looks like it's easier to read than most books on traditional digital filters.

That I fully agree with.

Regards
Andrew

antto · Post by **antto** » Tue May 22, 2012 10:53 am

i looked at it
once again i realize that my brain is just incompatible with such matters
there are things i understand, and things i don't (like math)

oh well.. maybe after ~20 years.. naah

Book: The Art of VA Filter Design 2.1.2