Antialiased oscillator?

Nov 16, 2013 at 12:43pm

Antialiased oscillator?

Hello,

I’m using different oscillators in Max: cycle~, tri~, saw~,..
Although they are antialiased, I still get very weird noises in the upper range. Does anyone else have this problem too?

I uploaded a short .wav on wetransfer to state the problem:

https://www.wetransfer.com/downloads/0fac246eb0f67fe5ac4fa1c733fb0a4620131116202348/e4fdc5a8a0403b6aef5b8efcb9185bda20131116202348/2c2d88

tri~, an antialiased oscillator is used. The problem in the high register is also audible in the tri~ help file.

#271404
Nov 16, 2013 at 1:19pm

it… sounds very different from what it sounds like on my system.

How did you record it? What’s your Max audio settings? Which other objects are in the audio path?
It sounds really boosted in the low end, and the high notes are really hard to hear. On my system I *do* get banding going up there, at around 4khz I hear one really clearly, and at 8khz there’s some somewhat loud sidebands as well, and going upwards from there it gets worse…but never as problematic as in your sound, and never as low-pitched.

#271408
Nov 16, 2013 at 2:01pm

I’m sorry…I forgot to eliminate the low-pass filter. The problem is however even more clear without it:

https://www.wetransfer.com/downloads/f549cf7e2f4cb35b85af911bfa8c41ea20131116214943/c53edb15c9c127ef4f5396eaacddec7e20131116214943/5bf5f1

Probably there is something wrong in my patch, the tri~ help patch does sound better, but still with banding as you mention. Is there a way to solve this?

#271412
Nov 16, 2013 at 3:16pm

share your patch, otherwise no one can really help you without guessing a whole lot. This also sounds different than on my machine… Audiofiles aren’t a help beyond stating that you have banding in your sounds.

#271415
Nov 16, 2013 at 3:17pm

actually, I take that back: it sounds like you’re overdriving your output.

#271416
Nov 16, 2013 at 5:30pm

yes, actually my patch isn’t the issue. I will be able to solve the problem.
The “real” problem is the fact that the Max oscillators have sidebands at around 4 Khz.

there is probably no solution for this..?

#271423
Nov 17, 2013 at 9:11am

while cycle has interpolation, it is _not bandlimited like the other two you mentioned.

#271462
Nov 17, 2013 at 11:19am

The “real” problem is the fact that the Max oscillators have sidebands at around 4 Khz.

Well, no, I’m saying tri~ sounds nothing like your sample on my machine – it honestly does sound like you’re introducing odd harmonics, **which is why I asked about your patch**.

you can also see the sidebands in the tri~ help comparison thing.
And have you tried hipass-filtering below your fundamental?

Also, have you read about nyquist yet? tri~ generates very high frequency harmonics if you set your fundamental to 4khz, of course those will fold to some degree.

#271467
Nov 19, 2013 at 9:57am

Hello again, I didn’t notice your reply up till now. I know there was a problem in my patch. The “official” tri~ helppatch does sound very good, but even there I can still hear weard things in the high register, although of course not as obvious as my patch.

I’m not at home at the moment, I will do some research about nyquist and get back to you this evening, thanks for your help!

#271706

You must be logged in to reply to this topic.