KVR :: Instruments » Zero Delay Feedback Filter (How to test if your synth has a )- Xils-Lab White Paper - [View Original Topic]
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Lotuzia - Thu May 10, 2012 4:19 am
Zero Delay Feedback Filters A very simple test
The delay feedback problem in synthesis software emulation was first pointed out and named by Vadim Zavalishin, of Native Instruments back in 2008, but it was also mentioned some years before, under different names in several other papers.
What really matters is the effect on the sound. This is most apparent in how it alters the relationship between the filter frequency and the filter resonance (or emphasis)
In hardware analog synthesizers, the filter frequency and its resonance are almost independent. When one of them is being modified the other remains almost the same. Adding a delay in digital filter means computing the output of the filter with an input and the previous output creates a link between the cutoff frequency and the emphasis so modifying the frequency also modifies the emphasis.
Here is a simple test that you can make to figure out if you favorite soft synthesizer has a zero-delay-feedback filter. Apply a Mid Emphasis to the filter and sweep the filter through the full range.
With a 0df, the emphasis will keep almost the same value. In a filter design that does not manage the digital delay, the emphasis will increase as well as the frequency increases.
A commonly held belief is that non-0df filters are unable to produce sounds with rapid onset transients, like percussion because of the delay introduced. This is incorrect, the 1 delay lag is not perceived by the ear. The 0df filter problem affects sounds at more or less mid resonance settings, when the filter frequency is varying (when is generally the case).
For those who want to go find out more, and really get your geek on go here for a more scientific description of the 0df filter case.
The Test: You'll need a synthesizer (software of hardware) with a self-oscillating filter and a noise generator.
1. Open the noise generator level and mute the oscillators.
2. Set the filter frequency to a very noticeable value (500 Hz for instance)
3. Set the emphasis to a mid value (not to high, but enough to be noticeable)
4. Sweep the filter frequency toward the highest value.
In Zero Delay Feedback filters, the emphasis will remain the same, but in filters that do not manage this delay, the emphasis will grow until the filter self-oscillates.
Here you can see this test:
http://www.youtube.com/watch?v=AuR5haBJYss
Yes, It's "that" simple !
Final Note: Synths that are not equipped with 0df filters are definitely NOT "bad" synths. They have their own character, filters, etc, and in a lot of situations, you wont be able to tell the difference. The same applies to synths equipped with 0df filters: They COULD sound bad, as this is only ONE aspect of all the overall character of a synth.
At Xils-Lab we're always trying to better our algorithms, and the 0df part is no exception. There are several possibilities and approaches to achieve 0df filters in the digital world, and we hope that our own way to do things will continue to evolve and will allow us to keep on offering beautiful musical instruments in the future.
We hope that this test will be useful and fun for you.
LtZ
hakey - Thu May 10, 2012 4:56 am
Howard - Thu May 10, 2012 5:12 am
Lotuzia wrote:
In Zero Delay Feedback filters, the emphasis will remain the same, but in filters that do not manage this delay, the emphasis will grow until the filter self-oscillates
...(snip)
Yes, It's "that" simple!
Oh really? That test may be an indication, but it is not foolproof - cutoff and resonance can be linked by other means, resulting in a similar response ...(snip)
Yes, It's "that" simple!
Echoes in the Attic - Thu May 10, 2012 5:21 am
Read the in-depth article, good read. Now ditch the dongles and you might have a sale or two.
(You do realize that almost no synth plug-ins use dongles anymore...)
Acid Mitch - Thu May 10, 2012 5:25 am
Why wouldn't we just read the synth specs/marketing blurb instead of doing tests ?
It seems like it's the latest thing for devs to boast about, so they are bound to mention it. If it doesn't say "zero delay feedback filter "in the specs then it mostly likely doesn't have it.
Bronto Scorpio - Thu May 10, 2012 5:27 am
Ohh Cthulhu, KVR is a funny place these days.
I'll prepare my popcorn
Cheers
Dennis
hakey - Thu May 10, 2012 5:29 am
Going by that test, Zebra's XMF filter exhibits zero-delay-feedback behaviour!
Howard - Thu May 10, 2012 5:36 am
hakey wrote:
Going by that test, Zebra's XMF filter exhibits zero-delay-feedback behaviour!
(well, maybe not so shocked) Echoes in the Attic - Thu May 10, 2012 5:43 am
hakey wrote:
Going by that test, Zebra's XMF filter exhibits zero-delay-feedback behaviour!
Actually the question becomes, just what filters out there aren't 0df now? I don't htink I have any! Horray, all my synths just got even better!
mystran - Thu May 10, 2012 5:47 am
Lotuzia wrote:
In hardware analog synthesizers, the filter frequency and its resonance are almost independent. When one of them is being modified the other remains almost the same.
This is NOT true in general. It is true for certain specific topologies implemented in certain specific ways, but there are tons of examples where this is NOT the case (ie the analog originals are NOT well-behaved in such a sense). Further, many analog designs that have significantly non-linearities can further have dependencies between input signal levels vs. frequency and/or resonance.
Further, even if you took a specific analog topology that does have this independence property, you can still screw it up even with zero-delay design. Likewise you can make a non-zero-delay design appear to have this independence as far as the user is concerned, at least in simple tests.
It is true that when you model a "well-behaved" analog topology (eg OTA 4-pole cascade or SEM-style SVF or whatever) with zero-delay techniques, you will probably end up preserving the "well-behaved" nature of the original. Now take a transistor ladder instead, and the analog-original is unlikely to be very well-behaved to begin with (though you can rather easily model the resulting behavior as well, whether you're using zero-delay or not). There are also analog designs that don't have such independence even in their linear model.
I'm not against zero-delay design; it does generally do a better job in time-varying cases and it even in time-invariant cases it generally saves you from having to do some magic (=fancy math) to fix the independence (or dependence) properties, where as a zero-delay design usually preserves whatever it is that the original does.
hakey - Thu May 10, 2012 5:47 am
Echoes in the Attic wrote:
Actually the question becomes, just what filters out there aren't 0df now? I don't htink I have any! Horray, all my synths just got even better!
Indeed. Happy days!
mystran - Thu May 10, 2012 5:48 am
Echoes in the Attic wrote:
hakey wrote:
Going by that test, Zebra's XMF filter exhibits zero-delay-feedback behaviour!
Actually the question becomes, just what filters out there aren't 0df now? I don't htink I have any! Horray, all my synths just got even better!
You probably have tons. They just use some other methods to get the independence properties. It's not like you need to make a naive model even if there's some extra delays in the feedback paths. The whole thread is a joke.
izonin - Thu May 10, 2012 5:52 am
Lotuzia wrote:
Synths that are not equipped with 0df filters are definitely NOT "bad" synths. They have their own character, filters, etc, and in a lot of situations, you wont be able to tell the difference. The same applies to synths equipped with 0df filters: They COULD sound bad, as this is only ONE aspect of all the overall character of a synth.
LtZ
LtZ
When researching for an adequate filter for my Stargate project, I ported Vadims filter from Reaktor to SM. It didn't sound better than the stock one. The non-linearities are far more important for the character and the quality.
Bronto Scorpio - Thu May 10, 2012 5:55 am
Since a certain competitor has released a certain synth some developers seem to get a bit paranoid. I, and many others, will judge the sound with their ears. Pretty videos and pictures won't help here.
The saddest thing really is that XILS synths are really good! There is really no need for stuff like this.
The *really* sad thing is that the whole thing is a lie though! This is no accurate test. I don't have synth1 installed at the moment but I'm sure this test would show that it has 0-delay-whatever-latestmarketingphrase-0df filters. Which it doesn't and it sounds great nontheless.
Cheers
Dennis
hakey - Thu May 10, 2012 6:02 am
izonin wrote:
When researching for an adequate filter for my Stargate project, I ported Vadims filter from Reaktor to SM. It didn't sound better than the stock one. The non-linearities are far more important for the character and the quality.
Doesn't make sense. The whole point about 0DFb filters is that they do a better job of reproducing nonlinear (=feedback) behaviour.
Echoes in the Attic - Thu May 10, 2012 6:05 am
mystran wrote:
Echoes in the Attic wrote:
hakey wrote:
Going by that test, Zebra's XMF filter exhibits zero-delay-feedback behaviour!
Actually the question becomes, just what filters out there aren't 0df now? I don't htink I have any! Horray, all my synths just got even better!
You probably have tons. They just use some other methods to get the independence properties.
Ya I was joking.
toitoi - Thu May 10, 2012 6:05 am
Le Lotus Bleu Strikes Back
izonin - Thu May 10, 2012 6:07 am
hakey wrote:
izonin wrote:
When researching for an adequate filter for my Stargate project, I ported Vadims filter from Reaktor to SM. It didn't sound better than the stock one. The non-linearities are far more important for the character and the quality.
Doesn't make sense. The whole point about 0DFb filters is that they do a better job of reproducing nonlinear (=feedback) behaviour.
My point is that Diva's filters in non-zero (draft) mode sound a lot better than Vadim's zero-delay-feedback one. So 0DFb is no guarantee for good sound.
awol9000 - Thu May 10, 2012 6:11 am
SNORE............
braj - Thu May 10, 2012 6:24 am
I second the dongle as being the reason I avoid XILS synths.
vaisnava - Thu May 10, 2012 6:34 am
+1 ditch your dongle and I will stand in line.
Lotuzia - Thu May 10, 2012 7:23 am
toitoi wrote:
Le Lotus Bleu Strikes Back
Finally someone did get it
Else :
There are already some non dongled Xils synths ( Xils3 LE and PKBII Advanced player .)Be assured there will be more in the future.
These tests ( there are more tests in the advanced page, as there's more detailed information ) are not only for Xils synths, the interesting thing is that you can do them with all your synths, including your real analog ones. I did them with my 7 HW analog synths, and all did exhibit the same exact behaviour. Then some soft synths were tested, but well, you can now try them and do the same with your synth(s) That's all we provided, along with some explanations, only for those who like to read some ( as a poster stated, you dont need to perform these tests, there are infomercial blurbs )
Ltz
toitoi - Thu May 10, 2012 7:34 am
Is it the right guess? I like Tintin world a lot.
Lotuzia - Thu May 10, 2012 7:58 am
toitoi wrote:
Is it the right guess? I like Tintin world a lot.
Yes it is, I'm a fan too, and Lotuzia was the name of my 1rst Sorceress in Diablo II hardcore mode a long time ago, she never died, though Blizzard must have erased it by now, so I thought it might be a good idea to offer her some after life
I like magical names Richard_Synapse - Thu May 10, 2012 10:36 am
mystran wrote:
This is NOT true in general. It is true for certain specific topologies implemented in certain specific ways, but there are tons of examples where this is NOT the case (ie the analog originals are NOT well-behaved in such a sense). Further, many analog designs that have significantly non-linearities can further have dependencies between input signal levels vs. frequency and/or resonance.
Yep exactly. It pretty much reduces to a few well-behaved designs such as the Moog, and even that isn't 100% constant-Q. Besides constant-Q digital filters exist since ages. The interesting part is when the filters become nonlinear, such as in Diva. The 0df linear case seems somewhat overrated to me, after I experimented with that for a while. In Dune 2 we'll definitely employ nonlinear designs instead.
Richard
Bronto Scorpio - Thu May 10, 2012 10:40 am
Richard_Synapse wrote:
In Dune 2 we'll definitely employ nonlinear designs instead.
Nice
Can't wait to hear the results
Cheers
Dennis
pdxindy - Thu May 10, 2012 11:10 am
braj wrote:
I second the dongle as being the reason I avoid XILS synths.
Me too... I quite like them sonically... but no dongles for me!
Kriminal - Thu May 10, 2012 11:18 am
Lotuzia wrote:
blah blah blah...
Here is a simple test that you can make to figure out if you favorite soft synthesizer has a zero-delay-feedback filter...
blah blah blah
Here is a simple test that you can make to figure out if you favorite soft synthesizer has a zero-delay-feedback filter...
blah blah blah
just ask the developer, much less hassle
Kriminal - Thu May 10, 2012 11:19 am
braj wrote:
I second the dongle as being the reason I avoid XILS synths.
yes, thats one of the reasons
xavier - Thu May 10, 2012 11:19 am
Richard_Synapse wrote:
mystran wrote:
This is NOT true in general. It is true for certain specific topologies implemented in certain specific ways, but there are tons of examples where this is NOT the case (ie the analog originals are NOT well-behaved in such a sense). Further, many analog designs that have significantly non-linearities can further have dependencies between input signal levels vs. frequency and/or resonance.
Yep exactly. It pretty much reduces to a few well-behaved designs such as the Moog, and even that isn't 100% constant-Q. Besides constant-Q digital filters exist since ages. The interesting part is when the filters become nonlinear, such as in Diva. The 0df linear case seems somewhat overrated to me, after I experimented with that for a while. In Dune 2 we'll definitely employ nonlinear designs instead.
Richard
Hi,
I will explain a little deeper because it seems that something was misunderstood.
_ Take a non constant-Q hardware topology. Reproduce it with the needed delay(s) in the digital world. The links between the Q and the frequency you will get with this digital filter won't have nothing to do with the relation between the Q and the frequency of the hardware model.
_ Take a constant-Q digital filter which doesn't self-oscillate. A simple test can show that even the Q is independent of the frequency, the spectrum, due to the digital delay, is warped (here is an other consequence of the delay which is managed by the 2-poles XILS 3 filter).
But we are not talking here such a filters, but self-oscillating filters.
What was stated is that a self-oscillating digital filter which does need a non-linearity in its internal part (otherwise it would output infinite numbers) must compute the input and the output at the same time.
In the digital world, a delay is needed for this. Either you manage it and it doesn't change the filter characteristics, either you don't and the result won't be the same than the analogue model (what ever its topology).
Now this non-linearity can be done in very different way, giving very different sound and results. But this doesn't change the mathematics rules.
I hope this is a little more clear (despite my poor English)
Best regards
Xavier
Lotuzia - Thu May 10, 2012 11:54 am
Kriminal wrote:
Lotuzia wrote:
blah blah blah...
Here is a simple test that you can make to figure out if you favorite soft synthesizer has a zero-delay-feedback filter...
blah blah blah
Here is a simple test that you can make to figure out if you favorite soft synthesizer has a zero-delay-feedback filter...
blah blah blah
just ask the developer, much less hassle
Just dont read this thread, much less hassle for you.
We propose some test process, you dont need it, its ok, some other posters found it interesting, and its probably merely for this kind of people that this kind of threads might be usefull.
ariston - Thu May 10, 2012 12:09 pm
My new Grundig vacuum cleaner has a zero-delay feedback filter. It's a real blessing for those with allergies. Inexplicably, it failed this test, though.
This leaves only two possibilities: either the test is bogus, or Grundig lied about their product. Either way, a filter sweep with full resonance sure sounds sweet on it, but only on parquet flooring. On carpet, it tends to lose too much volume, and the transients are a bit muffled. Haven't tried it on the leather couch yet, but I'm optimistic.
My old Panasonic sure as hell couldn't get that sound, not even with 800W oversampling.
JoeCat - Thu May 10, 2012 12:15 pm
+1 ditch the dongle!
Kriminal - Thu May 10, 2012 12:19 pm
Lotuzia wrote:
Kriminal wrote:
Lotuzia wrote:
blah blah blah...
Here is a simple test that you can make to figure out if you favorite soft synthesizer has a zero-delay-feedback filter...
blah blah blah
Here is a simple test that you can make to figure out if you favorite soft synthesizer has a zero-delay-feedback filter...
blah blah blah
just ask the developer, much less hassle
Just dont read this thread, much less hassle for you.
We propose some test process, you dont need it, its ok, some other posters found it interesting, and its probably merely for this kind of people that this kind of threads might be usefull.
you mean stupid people?
What exactly is this thread about....trying to ptove xils has zdf and that 'other' companies dont?
Looks to me like very unsubtle trolling....
Bronto Scorpio - Thu May 10, 2012 12:23 pm
ariston wrote:
My new Grundig vacuum cleaner has a zero-delay feedback filter. It's a real blessing for those with allergies. Inexplicably, it failed this test, though.
This leaves only two possibilities: either the test is bogus, or Grundig lied about their product. Either way, a filter sweep with full resonance sure sounds sweet on it, but only on parquet flooring. On carpet, it tends to lose too much volume, and the transients are a bit muffled. Haven't tried it on the leather couch yet, but I'm optimistic.
My old Panasonic sure as hell couldn't get that sound, not even with 800W oversampling.
You need to buy the nonlinear analog summing engine for it to perform better on carpets.
This leaves only two possibilities: either the test is bogus, or Grundig lied about their product. Either way, a filter sweep with full resonance sure sounds sweet on it, but only on parquet flooring. On carpet, it tends to lose too much volume, and the transients are a bit muffled. Haven't tried it on the leather couch yet, but I'm optimistic.
My old Panasonic sure as hell couldn't get that sound, not even with 800W oversampling.
Cheers
Dennis
ariston - Thu May 10, 2012 12:32 pm
Bronto Scorpio wrote:
ariston wrote:
My new Grundig vacuum cleaner has a zero-delay feedback filter. It's a real blessing for those with allergies. Inexplicably, it failed this test, though.
This leaves only two possibilities: either the test is bogus, or Grundig lied about their product. Either way, a filter sweep with full resonance sure sounds sweet on it, but only on parquet flooring. On carpet, it tends to lose too much volume, and the transients are a bit muffled. Haven't tried it on the leather couch yet, but I'm optimistic.
My old Panasonic sure as hell couldn't get that sound, not even with 800W oversampling.
You need to buy the nonlinear analog summing engine for it to perform better on carpets.
This leaves only two possibilities: either the test is bogus, or Grundig lied about their product. Either way, a filter sweep with full resonance sure sounds sweet on it, but only on parquet flooring. On carpet, it tends to lose too much volume, and the transients are a bit muffled. Haven't tried it on the leather couch yet, but I'm optimistic.
My old Panasonic sure as hell couldn't get that sound, not even with 800W oversampling.
Cheers
Dennis
Really? Damn, it was already expensive... and very taxing on the electrical supply, but as long as we only run one instance, it's okay.
At least we only have one small carpet in the house, so it's no biggie. I'll just vacuum around it.
Lotuzia - Thu May 10, 2012 12:32 pm
Bronto Scorpio wrote:
Since a certain competitor has released a certain synth some developers seem to get a bit paranoid. I, and many others, will judge the sound with their ears. Pretty videos and pictures won't help here.
The saddest thing really is that XILS synths are really good! There is really no need for stuff like this.
The *really* sad thing is that the whole thing is a lie though! This is no accurate test. I don't have synth1 installed at the moment but I'm sure this test would show that it has 0-delay-whatever-latestmarketingphrase-0df filters. Which it doesn't and it sounds great nontheless.
Cheers
Dennis
The saddest thing really is that XILS synths are really good! There is really no need for stuff like this.
The *really* sad thing is that the whole thing is a lie though! This is no accurate test. I don't have synth1 installed at the moment but I'm sure this test would show that it has 0-delay-whatever-latestmarketingphrase-0df filters. Which it doesn't and it sounds great nontheless.
Cheers
Dennis
First : The really sad thing imho is that we did not wait that Saurus ( I can give names if you're too shy ) was released for saying that Xils-Lab synths have 0df filters, just fyi.... So your statement "since a certain competitor .... " is just false from the beginning.
Then : And as for beeing accused to be lying , we're waiting for your Synth1 tests ( because you said you were sure of that ). Then we'll see ........
Its curious like when some other people are mentioning 0df filters for other synths its the alpha and omega of superiority, and when we just say " hey we have some little tests to allow you to see if your synths have it, and btw there are other synths than the ones always mentioned by certain people " we get flamed this way.
Its was very interesting in this regard to see that the Saurus thread just began like this : same people expressing "more than doubts" on the fact they could have done a 0df filter. " Mamma mia did they dare ? they must be lyers " So i dont know who is afraid of "competing products" but eventually these are definitely not people like us
Btw I should not have to say it, but as Richard mentioned this I think I could add some info as well : Of course Xils synths have non linear behaviour.
Then the test is valid for selfosc LPF filters, this is clearly mentioned in the beginning of the OP (not Biquad filters for example ) Even if its very simple, one has still to observe a few minimal rules to run it.
Nielzie - Thu May 10, 2012 12:43 pm
Hmmm another thread seems to get derailed from proper gentle discussions.
Shouldn't this just be a normal discussion about how to measure a zdf in digital synths?
Such agressive "anti-marketing" going on these days, why?
Lotuzia - Thu May 10, 2012 12:46 pm
Kriminal wrote:
Lotuzia wrote:
Kriminal wrote:
Lotuzia wrote:
blah blah blah...
Here is a simple test that you can make to figure out if you favorite soft synthesizer has a zero-delay-feedback filter...
blah blah blah
Here is a simple test that you can make to figure out if you favorite soft synthesizer has a zero-delay-feedback filter...
blah blah blah
just ask the developer, much less hassle
Just dont read this thread, much less hassle for you.
We propose some test process, you dont need it, its ok, some other posters found it interesting, and its probably merely for this kind of people that this kind of threads might be usefull.
you mean stupid people?
What exactly is this thread about....trying to ptove xils has zdf and that 'other' companies dont?
Looks to me like very unsubtle trolling....
Who did mention stupid people ? Just you. SO I'll leave you this statement.
Ours was that people who might be interested in this problem could find some information, together with some audio tests. Use it, dont use it, its beyond us.
So The purpose of this test is to determine if any synth ( with the filter type specidied ) has a 0df filter. You can also make this test with real analog gear btw.
Any synth. ........
Nielzie - Thu May 10, 2012 12:49 pm
I want the old KVR (until 2011) back!
ariston - Thu May 10, 2012 12:49 pm
Did anyone mention yet that this thread and its devious little intentions are utterly repugnant?
And the sad fact is, most consumers couldn't care less about the tech behind the scenes. We have ears, and we have experience, and no amount of thinly-veiled sand-kicking or pseudo-scientific testing will change that.
Respect to Xavier for his great work, I would very likely already own all three Xils synths were it not for ye dongle (no, I don't appreciate cut-down versions, I want the real deal). But maybe he should get someone else to do his "marketing" here, this boatload of half-digested crap must be hurting the business by now.
Kriminal - Thu May 10, 2012 12:57 pm
Lotuzia wrote:
Ours was that people who might be interested in this problem
what problem is that exactly???
Lotuzia wrote:
So The purpose of this test is to determine if any synth ( with the filter type specidied ) has a 0df filter. You can also make this test with real analog gear btw.
Any synth. ........
and? your point is? do you really think everyone is going to rush out and test all their synths ??? to what benefit exactly?
funny how you/xils never mentioned this until another company released a synth with zdf.....
too many saurus/diva threads for you recently????
Kriminal - Thu May 10, 2012 12:58 pm
ariston wrote:
Did anyone mention yet that this thread and its devious little intentions are utterly repugnant?
And the sad fact is, most consumers couldn't care less about the tech behind the scenes. We have ears, and we have experience, and no amount of thinly-veiled sand-kicking or pseudo-scientific testing will change that.
Respect to Xavier for his great work, I would very likely already own all three Xils synths were it not for ye dongle (no, I don't appreciate cut-down versions, I want the real deal). But maybe he should get someone else to do his "marketing" here, this boatload of half-digested crap must be hurting the business by now.
And the sad fact is, most consumers couldn't care less about the tech behind the scenes. We have ears, and we have experience, and no amount of thinly-veiled sand-kicking or pseudo-scientific testing will change that.
Respect to Xavier for his great work, I would very likely already own all three Xils synths were it not for ye dongle (no, I don't appreciate cut-down versions, I want the real deal). But maybe he should get someone else to do his "marketing" here, this boatload of half-digested crap must be hurting the business by now.
hakey - Thu May 10, 2012 1:05 pm
Lotuzia wrote:
The purpose of this test is to determine if any synth has a 0df filter.
And it's a flawed test (as was pointed out almost immediately).
ChiTown24 - Thu May 10, 2012 1:06 pm
dalor - Thu May 10, 2012 1:09 pm
Most of us here work (entirely) in the digital domain. With new faster computers, we get new algorithms that seemed impossible years ago. And for some reason there seems to be resistance to move along to understand it. Maybe it comes across more like marketing instead of technology?
Lotuzia - Thu May 10, 2012 1:21 pm
ariston wrote:
Did anyone mention yet that this thread and its devious little intentions are utterly repugnant?
And the sad fact is, most consumers couldn't care less about the tech behind the scenes. We have ears, and we have experience, and no amount of thinly-veiled sand-kicking or pseudo-scientific testing will change that.
Respect to Xavier for his great work, I would very likely already own all three Xils synths were it not for ye dongle (no, I don't appreciate cut-down versions, I want the real deal). But maybe he should get someone else to do his "marketing" here, this boatload of half-digested crap must be hurting the business by now.
And the sad fact is, most consumers couldn't care less about the tech behind the scenes. We have ears, and we have experience, and no amount of thinly-veiled sand-kicking or pseudo-scientific testing will change that.
Respect to Xavier for his great work, I would very likely already own all three Xils synths were it not for ye dongle (no, I don't appreciate cut-down versions, I want the real deal). But maybe he should get someone else to do his "marketing" here, this boatload of half-digested crap must be hurting the business by now.
Its not a marketing thread, and we carefully checked and wrote together each word of both test pages, with Xavier, knowing that we would be attacked by the thought police, whose main task is accusing people to lie, to be utterly repugnant, etc. So your accusation of pseudo scientific testing will go straight to Xavier's heart. We're waiting for more.
Btw you dont know who I am : I developped some UI concepts, some GUI modules, some audio concept modules, as well as many other things with Xils-Lab, and also manages the sound design department. You can read the manuals if you're interested into that. I talk on Kvr mainly because my english might be just a bit better than Xavier's one.
Btw people are not stupid, and the honnest reader will know in a flash who show their cool face in this threadn and who is trolling, for obvious reasons.
Whatever the trolling in this thread, people who want it have now access to some information about 0df filters, you can say its useless, and that people dont care ( I know you like to speak as if you were all the people in one person ) but my opinion is that people are smart enough to make their own decisions : We propose, and they take it or leave it ( its a bit like democraty, if you know what I mean )
PS ; And keep your vacuum cleaner preciously, maybe in 20 years you'll sell it at the better price than an Xpander
LtZ
Lotuzia - Thu May 10, 2012 1:33 pm
And then I will not answer to trolls; especially people asking the same question that were already answered two posts before ( like "funny how you/xils never mentioned this until another company released a synth with zdf..... ") I have evidences of all that, but its useless.
So dear reader, feel welcomed if you find this thread interesting, and want to discuss it sincerely, OR feel welcomed if you are not interested in this thread, its only for information, and/or feel even welcomed if you intend to troll and trash this thread like you did with so many other ones. ( but I cant answer to you in this case.....
)
LtZ
ariston - Thu May 10, 2012 1:42 pm
Lotuzia wrote:
Btw you dont know who I am : I developped some UI concepts, some GUI modules, some audio concept modules, as well as many other things with Xils-Lab, and also manages the sound design department. You can read the manuals if you're interested into that. I talk on Kvr mainly because my english might be just a bit better than Xavier's one.
Thanks for the info. I'll be sure to remember that the next time you claim not to be closely affiliated with Xils (and, thus, your opinions and posts are purely personal ones, bat eyelids innocently nudge nudge shrug). Remember that, or do I have to do a search and post it here?
I have to admit that I'm sad about aggravating Xavier's heart by praising his work unto the high heavens. Maybe the shock of it all will make him drop the dongle.
kmonkey - Thu May 10, 2012 1:51 pm
Some really really weird individuals with weird intentions here. I don't get it. OP clearly stated what this thread is about. I am bad at english but even i could get it.
I for once i am interested to know about this stuff a little bit more. I found this interesting. What is wrong with that?
Half year ago we had aliasing hunters yet noone accused anyone for "unsubtle trolling" or trying to make marketing or whatever.
Like i said before it is cruel point of time for plugin developers(well it is only on KVR actually). Just with the moment some dev post something there are dozen of ego trippers trying to fire up some kind of conspiracy...It makes you wonder about some people..
For the second time in my life i am reaching for "mute" option..
Lotuzia - Thu May 10, 2012 1:54 pm
Echoes in the Attic wrote:
Read the in-depth article, good read. Now ditch the dongles and you might have a sale or two.
(You do realize that almost no synth plug-ins use dongles anymore...)
(You do realize that almost no synth plug-ins use dongles anymore...)
Thanks Echoes,
Yes there will be some dongleless synths. Atm there are already some, the Xils3 LE is a full modular synth for .... 39$ .....
But there will be more.
raikard233 - Thu May 10, 2012 1:56 pm
kmonkey wrote:
Some really really weird individuals with weird intentions here. I don't get it. OP clearly stated what this thread is about.
I for once i am interested to know about this stuff a little bit more. I found this interesting. What is wrong with that?
I for once i am interested to know about this stuff a little bit more. I found this interesting. What is wrong with that?
Indeed.
Lotuzia - Thu May 10, 2012 2:11 pm
kmonkey wrote:
Some really really weird individuals with weird intentions here. I don't get it. OP clearly stated what this thread is about. I am bad at english but even i could get it.
I for once i am interested to know about this stuff a little bit more. I found this interesting. What is wrong with that?
Half year ago we had aliasing hunters yet noone accused anyone for "unsubtle trolling" or trying to make marketing or whatever.
Like i said before it is cruel point of time for plugin developers(well it is only on KVR actually). Just with the moment some dev post something there are dozen of ego trippers trying to fire up some kind of conspiracy...It makes you wonder about some people..
For the second time in my life i am reaching for "mute" option..
I for once i am interested to know about this stuff a little bit more. I found this interesting. What is wrong with that?
Half year ago we had aliasing hunters yet noone accused anyone for "unsubtle trolling" or trying to make marketing or whatever.
Like i said before it is cruel point of time for plugin developers(well it is only on KVR actually). Just with the moment some dev post something there are dozen of ego trippers trying to fire up some kind of conspiracy...It makes you wonder about some people..
For the second time in my life i am reaching for "mute" option..
Simple Thank You Kmonkey,
I'm glad you could find some usefull info.
Aiynzahev - Thu May 10, 2012 2:44 pm
kmonkey wrote:
Some really really weird individuals with weird intentions here. I don't get it. OP clearly stated what this thread is about. I am bad at english but even i could get it.
I for once i am interested to know about this stuff a little bit more. I found this interesting. What is wrong with that?
Half year ago we had aliasing hunters yet noone accused anyone for "unsubtle trolling" or trying to make marketing or whatever.
Like i said before it is cruel point of time for plugin developers(well it is only on KVR actually). Just with the moment some dev post something there are dozen of ego trippers trying to fire up some kind of conspiracy...It makes you wonder about some people..
For the second time in my life i am reaching for "mute" option..
I for once i am interested to know about this stuff a little bit more. I found this interesting. What is wrong with that?
Half year ago we had aliasing hunters yet noone accused anyone for "unsubtle trolling" or trying to make marketing or whatever.
Like i said before it is cruel point of time for plugin developers(well it is only on KVR actually). Just with the moment some dev post something there are dozen of ego trippers trying to fire up some kind of conspiracy...It makes you wonder about some people..
For the second time in my life i am reaching for "mute" option..
I have to concur. Though I wouldn't say the individuals are weird, but there is a lot of strange undercurrent.
There are a few things we need to look at with KVR. I often ask myself what I think I will find here. In reality KVR has been a nice place to read about what I have interests in and it has even sparked new interests for me. Speaking with other enthusiasts and professionals has been a benefit.
On the other hand there are the developers and those who have something to sell. For a while I considered not posting information about my own future releases as I feel the KVR has been overwhelmed with advertising lately.
After thinking about it some more I have noticed there either is not as much going on here as there used to be or I have lost some of the interests I had previously. Either way, advertising has benefited me also to some degree as I would not have heard about many of the synths, or known much about them, if it were not for the discussions here. So that side of it is useful also.
All that said, it takes away from the usefulness when threads are diverted so much. If I do not care about a topic, I either don't view it or I don't post. That keeps the "noise" pollution down so people can get on with the information.
If you disagree with the facts, that's another thing altogether and it fits, but I think "following" people around and taking jabs at them on every other corner really does nothing for anything.
I am not seeking to belittle anyone, but just think about it logically.
zvenx - Thu May 10, 2012 3:08 pm
raikard233 wrote:
.....
Indeed.
kmonkey wrote:
............ OP clearly stated what this thread is about.
I for once i am interested to know about this stuff a little bit more. I found this interesting. What is wrong with that?
I for once i am interested to know about this stuff a little bit more. I found this interesting. What is wrong with that?
Indeed.
+1
rsp
xx JPRacer xx - Thu May 10, 2012 4:04 pm
Richard_Synapse wrote:
In Dune 2 we'll definitely employ nonlinear designs instead.
ETA? xh3rv - Thu May 10, 2012 7:33 pm
Lotuzia wrote:
Its curious like when some other people are mentioning 0df filters for other synths its the alpha and omega of superiority
It's too simple to say just emulating analog gear is superior, but two related statements I think are valid. First, the better s-plane filter simulation with all other things being equal sounds better; second, there are characteristics of analog technology that sound good. Ultimately there are quantitative differences between the output of one filter technology versus another that I think eventually correlate to these pretty uncontroversial statements.
I'm much less certain how much these two overlap - what is it about emulating better is also sounding better. Somewhere in the overlap I think is really promising stuff, I think we'll find out over time and there should be *lots* of great sounding stuff along the way from many developers.
aciddose - Thu May 10, 2012 8:14 pm
problem with zero-delay filters is they don't solve the aliasing issue. it still requires massive over-sampling of about 8x-16x to get anywhere near where you want to be. by that time the filter is so expensive you might have considered using an analog one instead.
that said, technology advancements are good. the fact we have some insignificant advancement isn't insignificant itself - it could lead to significant advancements in the future.
crappy waveform wave-tables lead to the concept of minblep tables and minblamp tables which have replaced all previous technologies. the only reason older technologies exist is the difficulty of properly implementing the new ones. so blit integrators still exist in major commercial products for example even though the technology is completely obsolete.
http://www.togo.dejavuandcompany.com/Trippix/11%20Paris/16%20wooden%20plow.jpg
http://www.tomsihantiquetractors.com/4%20bottom%20plow.jpg
when you go from one basic technology to a more advanced and refined one, you drop most of the unskilled producers. audio software was once produced easily by amatures. in a few years that will no longer be possible and only very few skilled in the art will remain.
http://www.dmiblog.com/archives/Shovel%20ready.jpg
http://www.foxheavyequipmentoperator.com/images/excavator1.jpg
izonin - Thu May 10, 2012 9:40 pm
aciddose wrote:
when you go from one basic technology to a more advanced and refined one, you drop most of the unskilled producers. audio software was once produced easily by amatures. in a few years that will no longer be possible and only very few skilled in the art will remain.
Good synths can still be produced by amateurs from high quality modules. With minBLEP osc's and decent filter modules for SE or SM, I don't see the problem.
ariston - Thu May 10, 2012 10:34 pm
kmonkey wrote:
Some really really weird individuals with weird intentions here. I don't get it. OP clearly stated what this thread is about. I am bad at english but even i could get it.
The problem is not the content of the message, it is the intention. This is a "thing" that has been festering over several threads for months now, and if you haven't caught up with that then I appreciate you not knowing what "it" is all about. I won't rehash it now, the individual in question knows what "it's" about, and methinks he doth protest too much. But if you like to be fooled by that, then go ahead.
Once again, I'm not debating the content. Now let's hear some audio examples of your tests.
carrieres - Fri May 11, 2012 12:30 am
you are just pretending that we are fooled, we need your help to see the true !
instead of insulting everyone, the poster and people agreeing, you should make more music, you will see all the love around
aciddose - Fri May 11, 2012 12:48 am
izonin wrote:
aciddose wrote:
when you go from one basic technology to a more advanced and refined one, you drop most of the unskilled producers. audio software was once produced easily by amatures. in a few years that will no longer be possible and only very few skilled in the art will remain.
Good synths can still be produced by amateurs from high quality modules. With minBLEP osc's and decent filter modules for SE or SM, I don't see the problem.
there won't be one as long as someone is willing to produce those modules. more likely they'll become commercial in the future with only low tech modules available for free. once in a while you'll find someone willing to produce the good stuff but as the time investment increases we'll need to see more open-source reference implementations if we ever hope to maintain free software.
you'll start to see patents on this stuff soon.
ariston - Fri May 11, 2012 1:14 am
carrieres wrote:
you are just pretending that we are fooled, we need your help to see the true !
I never mentioned "truth", I'm just giving my POV; I'm sure you don't need my help for anything. You don't see it my way, I'm fine with that. I see BS, I call BS. Simple.
Last post in this thread, promise. I'll let you get on with your fascinating technical discussion - may it help you make better music. I also solemnly vow never to post anything regarding Mr. Shrug or his dealings here ever again. Best for all concerned, I'm sure.
SadPuppyBlues - Fri May 11, 2012 1:17 am
aciddose wrote:
there won't be one as long as someone is willing to produce those modules. more likely they'll become commercial in the future with only low tech modules available for free. once in a while you'll find someone willing to produce the good stuff but as the time investment increases we'll need to see more open-source reference implementations if we ever hope to maintain free software.
you'll start to see patents on this stuff soon.
you'll start to see patents on this stuff soon.
This seems less like a scenario where only the very skilled are putting out stuff, than only those with the most buying power.
carrieres - Fri May 11, 2012 1:20 am
thank you, it's fine, i just felt that you were a bit rude or harsh, it's obscuring your goal, but i appreciate your POV
izonin - Fri May 11, 2012 1:22 am
aciddose wrote:
izonin wrote:
aciddose wrote:
when you go from one basic technology to a more advanced and refined one, you drop most of the unskilled producers. audio software was once produced easily by amatures. in a few years that will no longer be possible and only very few skilled in the art will remain.
Good synths can still be produced by amateurs from high quality modules. With minBLEP osc's and decent filter modules for SE or SM, I don't see the problem.
there won't be one as long as someone is willing to produce those modules. more likely they'll become commercial in the future with only low tech modules available for free. once in a while you'll find someone willing to produce the good stuff but as the time investment increases we'll need to see more open-source reference implementations if we ever hope to maintain free software.
you'll start to see patents on this stuff soon.
But the very creators of SynthEdit and SynthMaker are advanced producers. Those modules will ship with the future versions of the software, once the technology becomes common.
Lotuzia - Fri May 11, 2012 1:43 am
SadPuppyBlues wrote:
aciddose wrote:
there won't be one as long as someone is willing to produce those modules. more likely they'll become commercial in the future with only low tech modules available for free. once in a while you'll find someone willing to produce the good stuff but as the time investment increases we'll need to see more open-source reference implementations if we ever hope to maintain free software.
you'll start to see patents on this stuff soon.
you'll start to see patents on this stuff soon.
This seems less like a scenario where only the very skilled are putting out stuff, than only those with the most buying power.
Its a bit of an off topic discussion, but I think that freeware developpers will also benefit of such technical points debated as the ones discussed in this thread. Its probably more easy to solve a problem when you're aware that there is a problem, and when it is documented.
Otoh, a synth developement cycle for us is around one year long, sometimes more. So its true that even for very dedicated freeware developers, it might be a bit hard to spend so much time and work on a project. This said overskilled/genius developers can exist in both worlds, freeware or commercial, maybe the commercial way allows them to better their ideas and refines them over time in a less painless way. I can only speak for myself, but I dont have the same POV on VSTI than I had years before, and its just because I was able to spend a lot of time to think about them ( of course I'm not including myself in the genius category ) and this time was autorised to me by the fact that I could get paid for the time I used to think about new concepts, new approaches of the modulation schemes, of the musical gesture etc when I was doing soundbanks for various manufacturers. Spending 8 hours a day on synths for some years is not a bad experience.
LtZ
JimmiG - Sun May 13, 2012 3:15 am
Maybe people who don't really understand DSP programming (me included) originally read a bit too much into the term zero-delay-feedback filters and attributed too much of DIVA's sound to this particular feature.
Here's the blurb from DIVA:s page (emphasis by me)
Quote:
The oscillators, filters and envelopes closely model components found in some of the great monophonic and polyphonic synthesizers of yesteryear. Modules can be mixed and matched so you can build hybrids, but what sets DIVA apart is the sheer authenticity of the analogue sound. This comes at the cost of quite a high CPU-hit, but we think it was worth it: Diva is the first native software synth that applies methods from industrial circuit simulators (e.g. PSpice) in realtime. The behaviour of zero-delay-feedback filters when pushed to the limit clearly demonstrates the advantages of this groundbreaking approach.
It doesn't say anywhere that DIVA is the first or only synth that uses zero-delay-feedback filters. It doesn't even say that this particular feature is what causes the high CPU usage or produces the great sound quality.
The way I interpret this text, is that the big feature, is the implementation circuit simulations in realtime. Then it goes on to mention the behavior of zero-delay-feedback filters (used as a general term, not as a feature unique to DIVA) as a great way to demonstrate the advantage of the technology described in the previous sentence (which doesn't even mention ZDF-filters at all).
So here's how I read the text:
1. DIVA applies methods from industrial circuit simulators. This gives it excellent sound quality, but also a high CPU usage.
2. The behavior of its ZDF-filters is a great way to demonstrate #1.
@midnight - Sun May 13, 2012 5:31 am
Does anybody know if Fabfilter's filters are zero delay feedback? I'm assuming not since they've been around since about 2004.
nineofkings - Sun May 13, 2012 5:44 am
@midnight wrote:
Does anybody know if Fabfilter's filters are zero delay feedback? I'm assuming not since they've been around since about 2004.
Why don't you test it?
Arksun - Sun May 13, 2012 5:49 am
My idea of a good filter, I press a note on the keyboard, I hear the sound, it sounds good to my ears. That's a good filter.
It sounds unpleasent to my ears, its a bad filter.
xh3rv - Sun May 13, 2012 6:30 am
Draft mode is 1-delay filters, so that gives some sense of how Diva's filters trades CPU cycles for sound quality/qualities.
The filter technology is necessary for certain sonic properties, but OTOH not necessary or sufficient for a more casual, less definable sonic 'goodness'.
izonin - Sun May 13, 2012 6:36 am
Arksun wrote:
My idea of a good filter, I press a note on the keyboard, I hear the sound, it sounds good to my ears. That's a good filter.
It sounds unpleasent to my ears, its a bad filter.
It sounds unpleasent to my ears, its a bad filter.
Do some tests with Diva in draft and divine mode. Might notice something you weren't aware of before. The z-1 draft has this comic/cartoony quality to it, while the zdf divine sounds more audio-realistic.
Arksun - Sun May 13, 2012 7:07 am
izonin wrote:
Arksun wrote:
My idea of a good filter, I press a note on the keyboard, I hear the sound, it sounds good to my ears. That's a good filter.
It sounds unpleasent to my ears, its a bad filter.
It sounds unpleasent to my ears, its a bad filter.
Do some tests with Diva in draft and divine mode. Might notice something you weren't aware of before. The z-1 draft has this comic/cartoony quality to it, while the zdf divine sounds more audio-realistic.
I am very aware of the difference in sound of the filter in Diva at different quality settings, particuarly the difference between draft - fast/great/divine. No additoinal tests required
My point is that for me personally I really don't care what goes on under the hood, unless its part of a bug solving thing for example if there was say a DC offset issue with a synth I might analyse n try and help the developer get to the root of the problem.
I will also go one step further and say that for some particular types of sounds, draft mode in Diva works can work better than the higher quality modes. And by better I mean in getting a particular kind of sound suited to genre and taste, not authenticity to some old vintage piece of equipment.
One mans awesome bright trance lead is anothers horrible plasticy lifeless sound, and vice versa. To argue that one particular way is the 'correct' way when it comes to something as subjective as sound and music in this instance is a bit silly. Maybe something as obvious as hideous amounts of aliasing sure, but this is different in my view.
For example, BigTones presets were designed in draft and thus to work at their intended filter response ideal in draft mode .But again its a matter of taste, we have the choice, of multiple quality settings, which is a nice touch.
There are times I want a really organic filter sound that sounds like its running through big chunks of hardware, and there are times I want a glassy pure filter sound, or a very resonant sharp filter sound, or a warm but very smooth analog/digital hybrid sound, or a very bright digital filter sound. Depends what mood I'm in, what I'm trying to accomplish, how I feel it'll suit a sound in a particular mix. No right or wrong way here.
Got nothing against marketing, its part of business, and it works, I'm just saying for me personally, I just play, I just listen, if I like the sound of it, thumbs up from me.
TheoM - Sun May 13, 2012 7:41 am
vaisnava wrote:
+1 ditch your dongle and I will stand in line.
just like to add on the flipside,
i only buy stuff now that HAS dongles, for ease of use with installation, and protection for my investment from the warez kiddies (at least i get to use it for a much longer time before it's "hacked")
TheoM - Sun May 13, 2012 7:46 am
Kriminal wrote:
ariston wrote:
Did anyone mention yet that this thread and its devious little intentions are utterly repugnant?
And the sad fact is, most consumers couldn't care less about the tech behind the scenes. We have ears, and we have experience, and no amount of thinly-veiled sand-kicking or pseudo-scientific testing will change that.
Respect to Xavier for his great work, I would very likely already own all three Xils synths were it not for ye dongle (no, I don't appreciate cut-down versions, I want the real deal). But maybe he should get someone else to do his "marketing" here, this boatload of half-digested crap must be hurting the business by now.
And the sad fact is, most consumers couldn't care less about the tech behind the scenes. We have ears, and we have experience, and no amount of thinly-veiled sand-kicking or pseudo-scientific testing will change that.
Respect to Xavier for his great work, I would very likely already own all three Xils synths were it not for ye dongle (no, I don't appreciate cut-down versions, I want the real deal). But maybe he should get someone else to do his "marketing" here, this boatload of half-digested crap must be hurting the business by now.
That is absolute and utter BS and it is members like the two of YOU who are derailing the thread.
There was no hidden meaning or trouble making here, it was simply an informational service to explain what these filters are all about and how you can test if your synth has them.
it is THAT simple...
everyone ELSE is turning it into a lotuzia hate fest and i am f**king tired of it.
Totally un called for behaviour.
Thanks for the information Lotuzia
Don't know whether it's correct or not as i am not technically minded like this but i did find it interesting nevertheless
TheoM - Sun May 13, 2012 7:48 am
ariston wrote:
kmonkey wrote:
Some really really weird individuals with weird intentions here. I don't get it. OP clearly stated what this thread is about. I am bad at english but even i could get it.
The problem is not the content of the message, it is the intention. This is a "thing" that has been festering over several threads for months now, and if you haven't caught up with that then I appreciate you not knowing what "it" is all about. I won't rehash it now, the individual in question knows what "it's" about, and methinks he doth protest too much. But if you like to be fooled by that, then go ahead.
Once again, I'm not debating the content. Now let's hear some audio examples of your tests.
there is no hidden intention other than the one you are creating.. and i have read ALL the back stories and topics related to what you are insinuating.. So please STOP trolling an information thread!
hakey - Sun May 13, 2012 7:53 am
Disinformation thread.
TheoM - Sun May 13, 2012 7:54 am
ps thanks for the reminder, just bought synthix, 20 seconds after i posted. What a great friggin synth! I am so glad i managed to sell a few things so i could get this! and Xavier provides amazing support and communications.
LONG LIVE THE DONGLE!
ariston - Sun May 13, 2012 10:30 am
ttoz wrote:
there is no hidden intention other than the one you are creating.. and i have read ALL the back stories and topics related to what you are insinuating.. So please STOP trolling an information thread!
Well, someone's lost his pacifier and is a bit cranky, it seems.
FYI: I did stop. You dragged it back up, days later I might add, and obviously felt that your opinion was so desperately needed that it required two posts. How does it feel to troll and obscure an information thread by accusing someone else of trolling? Can you spell "hypocrite"?
You don't see a hidden intention, I do. You can unclench your butt cheeks now, it's only a difference of opinion.
edit: Damn, broke my promise. See what you made me do? Well, back to anger-management classes.
TheoM - Sun May 13, 2012 10:45 am
I didn't see that it was days ago, in that case i am sorry. I honestly just saw fresh posts and did not think to look at your particular posting date. That is no BS, that is true.
Peace.
I do really feel Laurent was only at least trying to be helpful though..,
ok, going back to enjoy my synthix.. wow
ariston - Sun May 13, 2012 11:04 am
ttoz wrote:
I didn't see that it was days ago, in that case i am sorry. I honestly just saw fresh posts and did not think to look at your particular posting date. That is no BS, that is true.
Peace.
I do really feel Laurent was only at least trying to be helpful though..,
Peace.
I do really feel Laurent was only at least trying to be helpful though..,
Okay, fair enough, no harm done.
I still don't quite see the point of it all, beyond the fact that we've only been talking about 0 delay FB filters ever since you-know-who released you-know-what. It has been remarked that this proposed test is far from conclusive; I tend to agree. By this test, Z3ta2 has 0dfbfs. Does that even mean anything? The only software filters I've heard so far that are even close to you-know-what are the audio demos of the upcoming The Drop.
And, in the end, it's all about the sound. I might be curious as to the tech (just so I can bore my wife with the details), but it's all just numbers, innit? Isn't that why we pay talented devs like Urs and Xavier, so we don't have to worry about it?
rod_zero - Sun May 13, 2012 11:16 am
The point here is very simple:
Does the test can prove with 100% accuracy that a synth use zero delay filters?
If not, why?
Was the test designed to prove synths using one method and discriminate others?
Or, how many ways are there to "pass this test" using other methods?
hakey - Sun May 13, 2012 11:38 am
rod_zero wrote:
Does the test can prove with 100% accuracy that a synth use zero delay filters?
No. It's next to useless - many standard, non-0df filters will "pass" the test.
kv331 - Sun May 13, 2012 11:40 am
aciddose wrote:
problem with zero-delay filters is they don't solve the aliasing issue. it still requires massive over-sampling of about 8x-16x to get anywhere near where you want to be. by that time the filter is so expensive you might have considered using an analog one instead.
I havent played with ZDFs yet, but if they will still require high oversampling rates (>= x4), then in that case why would I use them? Because if there's oversampling (>=x4), then that'll compansate for the z-1 delay/phase errors to a certain extend, as nyquist frequency is divided by the oversampling factor... Please correct me if I am wrong guys!
Bulent
kv331 - Sun May 13, 2012 11:50 am
hakey wrote:
rod_zero wrote:
Does the test can prove with 100% accuracy that a synth use zero delay filters?
No. It's next to useless - many standard, non-0df filters will "pass" the test.
Yes, as long as they are designed correctly.
hakey - Sun May 13, 2012 11:55 am
kv331 wrote:
I havent played with ZDFs yet, but if they will still require high oversampling rates (>= x4), then in that case why would I use them? Because if there's oversampling (>=x4), then that'll compansate for the z-1 delay/phase errors to a certain extend, as nyquist frequency is divided by the oversampling
When you say ZDFs are you thinking about zero delay filters or zero delay *feedback* filters?
From what I understand, in the second case 0-delay makes a considerable difference as the effect of nonlinearities (=feedback) can be more accurately modelled.
kv331 - Sun May 13, 2012 11:59 am
hakey wrote:
When you say ZDFs are you thinking about zero delay filters or zero delay *feedback* filters?
From what I understand, in the second case 0-delay makes a considerable difference as the effect of nonlinearities (=feedback) can be more accurately modelled.
I think (!) meant zero delay feedback filters, where you get rid of z-1 in the feedback loop.
hakey - Sun May 13, 2012 12:11 pm
From what I understand, the problem is that in a real electrical circuit any feedback between input and output is instantaneous.
However, a digital model with 1-sample delay feedback uses the output from the last iteration as the input for feedback in the current iteration - ie it fails to model the effect of instantaneous feedback.
In contrast, a 0-DFb filter effectively uses the output from the current iteration as the input for feedback in the current iteration, and so models instantaneous feedback.
brok landers - Sun May 13, 2012 2:06 pm
Arksun wrote:
izonin wrote:
Arksun wrote:
My idea of a good filter, I press a note on the keyboard, I hear the sound, it sounds good to my ears. That's a good filter.
It sounds unpleasent to my ears, its a bad filter.
It sounds unpleasent to my ears, its a bad filter.
Do some tests with Diva in draft and divine mode. Might notice something you weren't aware of before. The z-1 draft has this comic/cartoony quality to it, while the zdf divine sounds more audio-realistic.
I am very aware of the difference in sound of the filter in Diva at different quality settings, particuarly the difference between draft - fast/great/divine. No additoinal tests required
My point is that for me personally I really don't care what goes on under the hood, unless its part of a bug solving thing for example if there was say a DC offset issue with a synth I might analyse n try and help the developer get to the root of the problem.
I will also go one step further and say that for some particular types of sounds, draft mode in Diva works can work better than the higher quality modes. And by better I mean in getting a particular kind of sound suited to genre and taste, not authenticity to some old vintage piece of equipment.
One mans awesome bright trance lead is anothers horrible plasticy lifeless sound, and vice versa. To argue that one particular way is the 'correct' way when it comes to something as subjective as sound and music in this instance is a bit silly. Maybe something as obvious as hideous amounts of aliasing sure, but this is different in my view.
For example, BigTones presets were designed in draft and thus to work at their intended filter response ideal in draft mode .But again its a matter of taste, we have the choice, of multiple quality settings, which is a nice touch.
There are times I want a really organic filter sound that sounds like its running through big chunks of hardware, and there are times I want a glassy pure filter sound, or a very resonant sharp filter sound, or a warm but very smooth analog/digital hybrid sound, or a very bright digital filter sound. Depends what mood I'm in, what I'm trying to accomplish, how I feel it'll suit a sound in a particular mix. No right or wrong way here.
Got nothing against marketing, its part of business, and it works, I'm just saying for me personally, I just play, I just listen, if I like the sound of it, thumbs up from me.
this summs it up rather nicely, imo.
also, i don't know, but i assume that the difference between draft and the higher quality modes in diva are not only the zero delay fb-mode, but way more enhancements, so i don't know if the comparsion between draft an the high q-modes fits clothes... i could be wrong on this though...
@midnight - Sun May 13, 2012 2:53 pm
Does anybody know how the Fabfilter filters stack up?
mystran - Sun May 13, 2012 3:34 pm
kv331 wrote:
aciddose wrote:
problem with zero-delay filters is they don't solve the aliasing issue. it still requires massive over-sampling of about 8x-16x to get anywhere near where you want to be. by that time the filter is so expensive you might have considered using an analog one instead.
I havent played with ZDFs yet, but if they will still require high oversampling rates (>= x4), then in that case why would I use them? Because if there's oversampling (>=x4), then that'll compansate for the z-1 delay/phase errors to a certain extend, as nyquist frequency is divided by the oversampling factor... Please correct me if I am wrong guys!
First of all, 4 times oversampling is hardly enough to fix a "classic" filter on it's own, and you still need quite a bit of fudge-factoring and you still have wrong phase relationships all over the place. Sure it helps, but not that much unfortunately (in practice the fudge-factoring helps a lot more).
That's not relevant for zero-delay though. The only real reason to oversample these is to get rid of aliasing (the BLT frequency warping gets fixed as a by-product). How much you need to oversample depends on how much you want to overdrive your filters, but 4 times oversampling can actually work quite well in practice (for quite a bit of saturation already). However, the filters would work perfectly fine (except for aliasing) without any oversampling whatsoever.
That said, there's not a whole lot of reason not to do it; in a modulated synth situation they don't even use meaningful additional CPU (on paper they use slightly more, but in practice it seem possibly to pipeline a bit better, so it kinda equals out). [edit: the main CPU cost is if you actually want to solve non-linearities in some fancy way; then you can throw as much CPU at it as you want.. but comparing apples to apples, doing non-linearities as cheap wave-shapers, it's pretty much the same]
aciddose - Sun May 13, 2012 5:04 pm
kv331 wrote:
I havent played with ZDFs yet, but if they will still require high oversampling rates (>= x4), then in that case why would I use them?
remove the "then in that case" and examine the "why would i use them?" question before you do anything. odds are you don't want to bother. which issues do they fix? if you're going from stable configuration A to zero-delay configuration B some have claimed there is an audible difference. i've never seen this demonstrated and my own tests only show an extreme cycles per sample increase.
xh3rv - Sun May 13, 2012 7:17 pm
Dunno if these links help but they're on topic.
I remember Urs linked this quite a while ago, before Diva was out: http://www.uaudio.com/blog/moog-multimode-filter-design - I don't remember the article so much but that it linked to this massive chunk: https://ccrma.stanford.edu/%7Estilti/papers/TimStilsonPhDThesis2006.pdf
Mostly over my head
At the very least the 'Gallery' appendix at the end of the PDF has some pretty pictures .
I think the root locus stuff suggests some things about oversampling versus different forms of computing the filter as a system, how filter attributes sort of become a fluid, chaotic s-plane phenomena inside a feedback loop. This is why 0dfb+bells&whistles becomes advantageous over z-plane filters. But, as far as doing this digitally - the uaudio.com blog post really does some hand-waving here, Stilson's thesis suggests several approaches. I have a pretty cursory familiarity with some of the mathematical tools that might work for solving something like this off-line, but on-line with low computational costs sounds like a *lot* of experimenting. So, I'm not able to speculate further (or as much as I have already
), but I did feel like these links were of interest.
As far as a test for 0dfb filter-ness, I think having just the filter to pass signals into might vastly simplify things ... I wonder if it ends up requiring analysis of a set of outputs from a carefully constructed set of inputs.
mcnoone - Sun May 13, 2012 8:27 pm
I get something close to 0 delay feedback, whenever I post my music noodling tracks in the music cafe.
I just call it 0 feedback though.
If there is any feedback, it's usually the delayed kind.
JoeCat - Sun May 13, 2012 8:42 pm
mcnoone wrote:
I get something close to 0 delay feedback, whenever I post my music noodling tracks in the music cafe.
I just call it 0 feedback though.
If there is any feedback, it's usually the delayed kind.
I just call it 0 feedback though.
If there is any feedback, it's usually the delayed kind.
Don't care 'bout 0DF. I want Rich, Corinthian Leather side panels
kv331 - Mon May 14, 2012 3:08 am
mystran wrote:
First of all, 4 times oversampling is hardly enough to fix a "classic" filter on it's own, and you still need quite a bit of fudge-factoring and you still have wrong phase relationships all over the place. Sure it helps, but not that much unfortunately (in practice the fudge-factoring helps a lot more).
Of course, one needs to use some tables, etc. to minimize the delay/phase errors, as mentioned in the following famous paper:
https://ccrma.stanford.edu/~stilti/papers/moogvcf.pdf
So, if they are used properly, and if you use >= x4 oversampling, ZDF wouldnt be necessary, that is my argument.
izonin - Mon May 14, 2012 3:22 am
kv331 wrote:
So, if they are used properly, and if you use >= x4 oversampling, ZDF wouldnt be necessary, that is my argument.
There's logic in that, but how do you explain the fact that Diva's filters sound different in draft and divine mode. Urs said that draft equals the highest setting in Ace, which is at least x4 oversampled.
kv331 - Mon May 14, 2012 3:37 am
[quote="izonin"]
kv331 wrote:
There's logic in that, but how do you explain the fact that Diva's filters sound different in draft and divine mode. Urs said that draft equals the highest setting in Ace, which is at least x4 oversampled.
Right now I cant
Once I dive into the topic, which is hopefuly this fall, I'll have something concrete to say
Urs - Mon May 14, 2012 3:43 am
izonin wrote:
kv331 wrote:
So, if they are used properly, and if you use >= x4 oversampling, ZDF wouldnt be necessary, that is my argument.
There's logic in that, but how do you explain the fact that Diva's filters sound different in draft and divine mode. Urs said that draft equals the highest setting in Ace, which is at least x4 oversampled.
Draft is 2x oversampled, Fast too (it equals ACE' highest quality setting in cpu usage and sound, I can elaborate about that elsewhere if needed). Draft and Fast are identical codewise, but Draft uses a z-1 solver while Fast uses an iterative zero-delay solver for the feedback with 12 bits accurracy. Fast is much better than Draft for fast modulations and of course you can easily hear how the resonance volume goes completely out of whack. All filters and modes are of course tuned so that self oscillation is in scale.
As for this discussion I'd happily add some insights, but I need to know for the OP first if this is a XILS thread or if it is open for other developers to join.