Strange portamento behaviour

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Ortseam
Posts: 25
Joined: 24 Jan 2019 13:44

Strange portamento behaviour

Post by Ortseam » 26 Jan 2019 21:29

This picture shows pressed MIDI keys and Karma's OSC frequency graph sharing the same time scale.

At the left side of the picture the one can see nice analog-like curve which you could expect from a real synth. If there's enough tіme for frequency to reach the new note value it behaves absolutely okay.

But when the new note changes earlier than the frequency fіnishes the portamento movement the one can see (and hear) the sudden jump to the frequency of just released note. The next portamento starts from this new point as shown at the right side of the picture.

I find this a bit frustrating. It's not what you'd expect from analog synth, which produces continual tone change without jumps in portamento mode.

Image

Could you please clarify what was the reason behind that or it can be considered as some kind of imperfection?

Thank you! Sorry for being so nagging. Maybe I'm a perfectionist...
Last edited by Ortseam on 26 Jan 2019 22:06, edited 2 times in total.

Ortseam
Posts: 25
Joined: 24 Jan 2019 13:44

Re: Strange portamento behaviour

Post by Ortseam » 26 Jan 2019 21:46

That's how other instrument acts with the same MIDI:
Image
I think it's more natural. New portamento always starts from the point where previous portamento stopped.

karmafx
Site Admin
Posts: 1162
Joined: 07 Mar 2005 16:37

Re: Strange portamento behaviour

Post by karmafx » 29 Jan 2019 21:38

Sounds like a bug to be honest. :oops: So don't feel bad btw.. Please keep "nagging" :D
The portamento works differently in mono vs poly modes. However, that said, it should not reset on release. That just sounds wrong.
If this happens on any patch I will look into it, otherwise please send me the repro steps.

Ortseam
Posts: 25
Joined: 24 Jan 2019 13:44

Re: Strange portamento behaviour

Post by Ortseam » 29 Jan 2019 22:09

Seems it happens at any patch but I'll check it out tomorrow. In any case I'll come back with the result.

karmafx
Site Admin
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Re: Strange portamento behaviour

Post by karmafx » 30 Jan 2019 07:28

Great! Thanks!!
EDIT: Meanwhile I will try to repro too.

Ortseam
Posts: 25
Joined: 24 Jan 2019 13:44

Re: Strange portamento behaviour

Post by Ortseam » 30 Jan 2019 16:07

Seems it's a global portamento problem. It's present an mono and legato modes, fixed and auto, linear and range-scaled.

karmafx
Site Admin
Posts: 1162
Joined: 07 Mar 2005 16:37

Re: Strange portamento behaviour

Post by karmafx » 01 Feb 2019 09:14

Yeah..I've reproed the bug.
Also found the offending line in the code.
So looks like this fix will be in v1.20. :lol:
That code was pretty old. So I'm surprised that this has gone unnoticed for so long.:oops:
The code was unique for mono/legato modes. So just to be sure, you did not encounter this issue in poly(phonic) modes, right?

I will need to test it some more though. If you would like a v1.20 beta, just let me know. :wink:

Ortseam
Posts: 25
Joined: 24 Jan 2019 13:44

Re: Strange portamento behaviour

Post by Ortseam » 01 Feb 2019 11:05

That's so nice that my report helped!
karmafx wrote:
01 Feb 2019 09:14
you did not encounter this issue in poly(phonic) modes, right?
I've never used portamento at poly mode, but I'll try today :)
UPD: tried it. Though I don't understand completely the logic of portamento behaviour in poly mode, I can safely say that there's no tone 'jumps' at note releases.
karmafx wrote:
01 Feb 2019 09:14
If you would like a v1.20 beta, just let me know.
I would be so much pleased to help Karma as beta tester. Feel free to send me your betas any time the testing is needed.

karmafx
Site Admin
Posts: 1162
Joined: 07 Mar 2005 16:37

Re: Strange portamento behaviour

Post by karmafx » 03 Mar 2019 11:30

Cool! I will get you a beta. 8)

Ortseam
Posts: 25
Joined: 24 Jan 2019 13:44

Re: Strange portamento behaviour

Post by Ortseam » 03 Mar 2019 21:36

Great! Thank you!

karmafx
Site Admin
Posts: 1162
Joined: 07 Mar 2005 16:37

Re: Strange portamento behaviour

Post by karmafx » 06 Mar 2019 22:41

:D 8)

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