About filter sweeps

Gonzo · Mar 12, 2003, 07:50 PM

Hello everybody:
First let me say that I know I'll be asking something that maybe isn't exactly at the top of your priorities at this time... but I consider it very important, (even more important than some fancier stuff) for those of us who are striving to obtain more professional results with our (admittedly) cheap SBLive's.
Well the fact is:
I'm extensively using the PhatEQ an LowPass filter to make filter sweeps taking advantage of KX Automation via midi, but I've found that there is a lot of zipper noise on fast sweeps, even on the highest midi resolution I can send to it.
I would like to know if you are aware of it, and if is it any cure other than using VST filters directly in the hosts.
I've read somewhere that good VST filters use some kind of interpolation between values to obtain a smoother sound (or something like this, I'm in no way a technically aware person), and I would like to know if it is possible to make at least a good sounding low pass filter that implements something like it.
I feel that we are very, but very close, to be able to compete with much more expensive cards, (at least in DSP features if not in sound), but this kind of tiny details are sometimes what puts apart professional solutions from well...ehem...toys...:-)
Please understand that I'm not implying that the LowPass filters doesn't sounds good to me, in fact I believe it's a nice sounding one, just that I would love to be able to treat it more like an analog unit where sweeps are so smooth...
It's a pity that until we can have a solution to this problem, we can only use the filters for static applications.
Anyway, I want to give my sincere thanks to the developers, I realize you've made a hell of a job just to get to were we are.

Gonzo
Uruguay

Max M. · Mar 12, 2003, 08:14 PM

this is thing "developers" know... yes, "fast sweeps" REQUIRE dsp interpolation of filter coefficients... So the special variants of filters should be made (with approx. twice bigger code inside)...

---
hehe, did anyone say that existing filters ARE optimized for use with kx automation?

---

anyway, thank you for "warning"....

Mar 12, 2003, 07:50 PM	#1
Gonzo DriverHeaven Junior Member Join Date: Feb 2003 Location: Uruguay Posts: 57 Rep Power: 0	About filter sweeps Hello everybody: First let me say that I know I'll be asking something that maybe isn't exactly at the top of your priorities at this time... but I consider it very important, (even more important than some fancier stuff) for those of us who are striving to obtain more professional results with our (admittedly) cheap SBLive's. Well the fact is: I'm extensively using the PhatEQ an LowPass filter to make filter sweeps taking advantage of KX Automation via midi, but I've found that there is a lot of zipper noise on fast sweeps, even on the highest midi resolution I can send to it. I would like to know if you are aware of it, and if is it any cure other than using VST filters directly in the hosts. I've read somewhere that good VST filters use some kind of interpolation between values to obtain a smoother sound (or something like this, I'm in no way a technically aware person), and I would like to know if it is possible to make at least a good sounding low pass filter that implements something like it. I feel that we are very, but very close, to be able to compete with much more expensive cards, (at least in DSP features if not in sound), but this kind of tiny details are sometimes what puts apart professional solutions from well...ehem...toys...:-) Please understand that I'm not implying that the LowPass filters doesn't sounds good to me, in fact I believe it's a nice sounding one, just that I would love to be able to treat it more like an analog unit where sweeps are so smooth... It's a pity that until we can have a solution to this problem, we can only use the filters for static applications. Anyway, I want to give my sincere thanks to the developers, I realize you've made a hell of a job just to get to were we are. Gonzo Uruguay

Mar 12, 2003, 08:14 PM	#2
Max M. h/h member-shmember Join Date: Dec 2002 Location: Evil Empire Posts: 2,639 Rep Power: 69	this is thing "developers" know... yes, "fast sweeps" REQUIRE dsp interpolation of filter coefficients... So the special variants of filters should be made (with approx. twice bigger code inside)... --- hehe, did anyone say that existing filters ARE optimized for use with kx automation? --- anyway, thank you for "warning".... __________________ Last edited by Max M.; Mar 13, 2003 at 06:01 AM.