Zero Delay Feedback Filter (How to test if your synth has a )- Xils-Lab White Paper -

[ariston]

edit: ach, I'm done with it.

[vurt]

BTW the release of Diva seemed to have another "side-effect" to the discussions here on KVR. as Diva is supposed to be the "holy grail" of VA synths now (which could be right) the discussions about other synths get mostly very aggressive end end up with "Diva is better and that other synth is crap" which is really unfair and like i already mentioned in another thread slowly starts to annoy me.
Ingo

why let it annoy you? theyre just opinions, everyone is entitled to their own opinion, and you are entitled, to agree, disagree or even ignore.
its not like someone is disrespecting your mother or anything, its just subjective discussion and opinions

Because besides having participated in the public beta and factory sound design for Diva i am also involved with both Xils Labs (especially Synthix, parts of the last expansion soundbank are from me) and Tone 2 (especially Saurus, doing sound design for it currently and joined the Tone2 beta team, also for ElectraX). And no, i am not directly employed at any of those companies, i got all of those synths with a normal purchase.
I have also beta tested the LeMasque Delay from Xils and will maybe participate in other tests too.
Maybe based on all that you could understand that i do not just ignore those discussions. BTW i am usually quite honest and i have also written a few critical words about the test presented at the OP of this thread.


Ingo

i didnt suggest you ignore the discussion, i suggested you ignored others opinions, theres a difference.
you cant expect everyone to agree with youre opinion, and you certainly cant expect everyone on a forum to be lets say "diplomatic" when voicing their own opinion. therefore sometimes its just best to leave that alone and just get on with your own thing
it makes one own life easier not to worry too much about such things.

[Ingonator]

The quote you used for your reply was more an observation i made based on several threads at KVR than a specific complaint.
Of course everyone is free to agree, disagree or just ignore that observation and of course it is also totally subjective...


Ingo

[mystran]

I suspect it's related to the thing they call "stiffness" actually. This is interesting to me, since given a fixed CPU budget, one might have to choose between "smooth" vs. "accurate".

True. Don't worry about cpu budget. Take pride in cycles and concentrate on sound. Why else would one bother?

Well, I think for practically every plugin I've released, someone has complained about the CPU use. I just try my best to spend most of it on whatever methods appear to give the best bang for the buck.

When we started doing numerical solvers for delayless feedback we honestly thought 1 voice per core. This has changed ever since, but we wouldn't have got there had we been afraid of cpu budget.

You're just looking at it from a different angle. You are saying: method A gives quality a(x), for some CPU cost x which we should not worry about, if a(x) is high enough.

Meanwhile I'm thinking: if I'm going to spend as much CPU as method A requires for quality a(x), can I find a method B that gives quality b(x) > a(x) for some sufficiently large value of x.

See how the discussion of actual CPU cost is orthogonal here.

[pdxindy]

BTW the release of Diva seemed to have another "side-effect" to the discussions here on KVR. as Diva is supposed to be the "holy grail" of VA synths now (which could be right) the discussions about other synths get mostly very aggressive end end up with "Diva is better and that other synth is crap" which is really unfair and like i already mentioned in another thread slowly starts to annoy me.

Ingo

This is not true... That is not where the discussion ends up. A couple people may say that and various others do not and your characterization is not accurately reflecting the range of opinions. And if a few people feel that Diva is simply better, then they are also stating their opinion and have a right to say it just as you have a right to disagree.

[pdxindy]

t i really hope that the situation here at KVR will get a bit more friendly than it is currently and that people accept that there are other good synths besides Diva and other good developers besides U-He...


Ingo

What people are you talking about? I think you should stop spreading this false idea. How many people in this or other recent threads think there are not other good developers and other good synths? Very few or none! You are making a false characterization.

[braj]

I also find it unfortunate to characterize any controversy in a thread as the fault of 'Diva users'. This does not take into account that the spectrum of personalities and motivations on all sides of a discussion contribute to the tone of the conversation. You make your bed and have to lay in it why be a baby about that?

[Ingonator]

t i really hope that the situation here at KVR will get a bit more friendly than it is currently and that people accept that there are other good synths besides Diva and other good developers besides U-He...


Ingo

What people are you talking about? I think you should stop spreading this false idea. How many people in this or other recent threads think there are not other good developers and other good synths? Very few or none! You are making a false characterization.

My statement in that quote might not be 100% correct and i already commented it on the last page but it's also dangerous to take a single sentence out of context. I have written at least two long posts (and several shorter ones) in the last pages which give a more complete picture about what i really wanted to point out. If all those together don't show what i really wanted to say it does not really make sense for me to comment it further as by my experiences at KVR this would lead only into more trouble.
BTW i avoided to give names like you asked for in your reply as first my remark was made in a more general manner and second i did not want to start a personal flame war here like others like to do sometimes.

I also find it unfortunate to characterize any controversy in a thread as the fault of 'Diva users'. This does not take into account that the spectrum of personalities and motivations on all sides of a discussion contribute to the tone of the conversation. You make your bed and have to lay in it why be a baby about that?

We two had a few problems/discussions in other threads recently and i really don't want to continue that here so i hope you understand if i don't further comment your reply.


It was proposed by someone that i should calm down and ignore the comments others do here on KVR so why others could no just do the same about mine. Instead they start quoting and discussing about single sentences of my in some cases quite long posts here so everything slowly starts to get out of context.


Ingo

[_leras]

As the technical discussion wore on, it became clear that this was a topic for experts.

You don't need to be an expert to realize that the digital filter designer may have put code in to adjust the resonance level across the cutoff range.

Since you have no way of knowing what's been done here, if anything, you can't make any assumptions based on measurements of the resonance peak levels across the cutoff range.

It's as simple as that. There's myriad other issues as well, but the show stopper is right there at that first assumption -- that they know how the filter is designed. As I've already pointed out, if you know how the filter is designed you don't NEED to test if it's zero delay feedback because you already know.

Oops, I was supposed to be done with this. But it just won't die as the OP and his phantom sponsor won't give it up.

Perhaps Xils only have the code for one generic filter type and don't have the chops to see things in different ways...

[pdxindy]

t i really hope that the situation here at KVR will get a bit more friendly than it is currently and that people accept that there are other good synths besides Diva and other good developers besides U-He...


Ingo

What people are you talking about? I think you should stop spreading this false idea. How many people in this or other recent threads think there are not other good developers and other good synths? Very few or none! You are making a false characterization.

My statement in that quote might not be 100% correct and i already commented it on the last page but it's also dangerous to take a single sentence out of context.

Ingo

I'm not asking for names... But how many people? I am not taking your comment out of context. It is a definitive self contained comment that stands clear enough on its own. You say that you hope that people accept that there are other good synths and developers. That implies that some number of people feel that way. So how many people are saying Diva is the only good synth and Urs the only good developer? How many people are saying that?

If you are going to make such a claim, back it up with something or please stop making it if you cannot.

[braj]

Illusion: something that deceives by producing a false or misleading impression of reality.

[Ingonator]

I'm not asking for names... But how many people? I am not taking your comment out of context. It is a definitive self contained comment that stands clear enough on its own. You say that you hope that people accept that there are other good synths and developers. That implies that some number of people feel that way. So how many people are saying Diva is the only good synth and Urs the only good developer? How many people are saying that?

If you are going to make such a claim, back it up with something or please stop making it if you cannot.

I already gave a hint that you also check my other posts at the last 2 pages, especially the 2 long ones.

This one should explain my post from the quote you posted in other words:

I think the forum is just about right. You're targeting users, not developers. What's odd is the timing. You should have posted this or something similar when your first product deploying this technology came out.

Hi Urs,

to be fair i am quite sure it was Diva that started the whole discussion (like i mentioned in my last long post). Then Tone2 followed the discussion or "blurb" with the release of Saurus and i'm quite sure they would not have discussed this without Diva being already released.
Later someone did not believe that the Xils synths have a 0df filter design (which obviously Xils Lab did not find really important before that discussion started recently) and so this thread is the logical consequence, no matter if it really makes sense or not or if the provided test is correct or not.

BTW the release of Diva seemed to have another "side-effect" to the discussions here on KVR. as Diva is supposed to be the "holy grail" of VA synths now (which could be right) the discussions about other synths get mostly very aggressive end end up with "Diva is better and that other synth is crap" which is really unfair and like i already mentioned in another thread slowly starts to annoy me.

As i use and like the 3 Xils synths (which i got before Diva and Saurus) and also both Diva and Saurus (for different reasons) i am feeling a bit uncomfortable in the current discussions and feel a bit like "sitting between the chairs" (not sure if i translated this correctly...). Anyway it would also not feel right if i just ignored those discussions and stay quiet. I hope you understand my point and as far as i know you i'm sure you do (but some others maybe not).


Ingo

This was my first long statement:

I'd be interested to know whose marketing blurb and bla-bla you're referring to, by the way. Tread carefully, though.

This is easy too. It was first started with Diva, before nobody including me didn't care about zero delay feedback filters. Later that as that "blurb" seemed to get more popular it was "adapted" by Tone2 for Saurus. I am quite sure Tone2 would have not mentioned it without the "blurb" produced by the release of Diva.

AFAIK this thread was done as someone here at KVR (hakey ?) stated that the Xils synths did not feature a 0df filter design which seemed to be wrong.

I appreciated that someone finally started to post a kind of test for this feature and another thank you goes to AQ for his own test (after i asked for another way to test this as the first one does not seem to be 100% safe).

It also seems to be the case that filters with high oversampling rates could get a similar behavior than 0df designs. Which could be nicely tested with AQ's test and PolyAna when using different quality settings.

Anyway personally i am not a really big friend of such technical discussions as first filters without 0df design are not bad per se and second there are many more facts that make a filter sound bad or good which seems to be the case for Diva too.
The settings which you need to detect the 0df behavior are settings which will not be used for most of the "usual" presets/sounds anyway. It's mostly about having quite high resonance at a quite high Cutoff frequency which would maybe apply to e.g. emulations of TB-303 like bass sounds. For "typical" analog sounds like e.g. Synth Strings or Synth Brass sounds you need only a small or no amount of Resonance so the 0df filter design is useless for those.
What makes the special sound of e.g. Diva is more about authentic behavior of the filter and Osc modules and about a good low end of the sound which to my knowledge is not based on the 0df filter design alone.

So while i own synths like the 3 Xils synths, Saurus, Diva and also PolyAna and like them all my opinion is that we did not really need this discussion about zero delay feedback design at all, incuding this thread. On the the hand like already mentioned it was NOT Xils Lab who started this discussion.

I also agree that none of the tests provided here are 100% foolproof but they give an idea about what happens with the resonance of certain filters which is also interesting for sound design purposes so maybe finally it has a use/sense at least for me anyway.

Just my 2 cents...


Ingo

BTW i was willing to stop the discussion here as someone (vurt to be precise) said i should cool down so i hope you understand that i will not repeat everything that i said just with other words. Your question about how many people i was talking about also doesn't matter for me as that was not part of my point.


Ingo

[braj]

To lighten the mood, some great use of synths here:

"It's the world of illusions
and Zero the Hero
is up to his ears
in the mysteries ...
No solution to speak of ...
round & round & round &
round & round
that's Zero going round again ... "

[Lotuzia]

To lighten the mood, some great use of synths here:

"It's the world of illusions
and Zero the Hero
is up to his ears
in the mysteries ...
No solution to speak of ...
round & round & round &
round & round
that's Zero going round again ... "

Nice music. We have a nice quote of Tim Blake, from Crystal Machine, about Xils emulation of the EMS he loves. Btw he used to be the very talented former Gong keyboardist

[braj]

Again, its a shame you use a dongle aint gonna happen for me until that is history.