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Author Topic: Possible bugs?  (Read 388 times)


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Possible bugs?
« on: February 05, 2021, 06:58:24 pm »
Hello Arturia!

I'm a happy owner of a new Polybrute (3 days now). I have noticed some behaviour that I find strange and I want to ask if this is something to worry about:

1. After editing a patch that includes FM 2 > 1, then either initializing a fresh patch or loading a "Default" template from page 5 (symptoms will be the same), the FM 2 > 1 parameter jumps to the value of the patch before after about 2-3 seconds. Or maybe to the position where the knob was left physically.
This happens in about 1 out of 3 times. I'm not sure if any other parameters jump values but for the FM parameter I'm certain.

2. The calibration of the Steiner filter of 2 voices doesn't want to stay very long. I have used the calibration routine about 8 times now, in cold and warm situations. It will be in tune for about 10 minutes, then one will slowly start drifting and then the other one as well, but less. The other 4 stay ok. The one voice that drifts more will drift out of audible range to the point where I first thought I had a dead filter, but really it's just so far drifted.
I test this by listening to the filter resonance and playing the keyboard with 100% tracking, VCO's turned off, no Brute factor.
Ladder filter is always ok.

Looking forward to reading your advice!


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Re: Possible bugs?
« Reply #1 on: February 15, 2021, 10:53:55 am »
Hello Ergoton,
sorry for the delay, i also saw your posts on Gearslutz in the meantime :)

Regarding your issues, could you please confirm that you are able to reproduce these with latest firmware

for your unexpected FM 2>1 parameter jump, i tried to reproduce it but without any success so far.

regarding calibration, i can tell that the calibration routine is way more solid than the one which was embedded on fw (which was the embedded firmware on first polybrute units received by customers so far). So i would suggest to perform another VCF calibration after having updated your unit to if not already done yet.

Looking forward to read you,


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