OB6 LFO bleed

OB6 LFO bleed
« on: June 05, 2023, 11:49:07 PM »
Hi,
After a new OB6 arrived, I can hear the LFO without hitting any note. Can be reproduced by initializing a patch, increasing the LFO frequency to audio rate and dialing in the LFO amount (either by initial amount or the modwheel). Changing the LFO shape is audible as well.

After executing the calibration all is fine, but as soon as I power the synth off and on, it again appears. I flushed the temperature table and ran the calibration several times. Also resettled global settings.

My firmware is 1.7.6 and since I cannot see this version available for download, I donít want to try downgrading.

Hopefully itís just a firmware bug. Anyone any other ideas?

Re: OB6 LFO bleed
« Reply #1 on: June 06, 2023, 06:14:23 AM »
On my OB-6 at full volume with the lfo on square wave I can only hear the lfo very faintly and only when the filter mode button is engaged. It's certainly nothing that I would have noticed otherwise.

Re: OB6 LFO bleed
« Reply #2 on: June 08, 2023, 01:41:05 AM »
Thanks for investigating. Actually for me as well it's when the filter mode is on, correct. Also I hear a tone, when X-Mod/VCO2 is on and Norm<->BP or Filtermode is enabled (e.g. patch 511 or 571).

When the LFO is a sawtooth and the mod wheel or Initial Amt is fully open it's very loud. I attached a file which demonstrates the init patch volume against the lfo filter mod volume, which is very noticable. I'd like to understand if this could be a bug and/or fixed by firmware or if it is a mechanical issue. Are you on firmware 1.7.6? Is the ratio between init patch and this tone the same for you?


Thanks and regards,
Dennis
« Last Edit: June 08, 2023, 01:47:14 AM by dennis1710 »

Re: OB6 LFO bleed
« Reply #3 on: June 20, 2023, 06:55:52 AM »
Thanks for investigating. Actually for me as well it's when the filter mode is on, correct. Also I hear a tone, when X-Mod/VCO2 is on and Norm<->BP or Filtermode is enabled (e.g. patch 511 or 571).

When the LFO is a sawtooth and the mod wheel or Initial Amt is fully open it's very loud. I attached a file which demonstrates the init patch volume against the lfo filter mod volume, which is very noticable. I'd like to understand if this could be a bug and/or fixed by firmware or if it is a mechanical issue. Are you on firmware 1.7.6? Is the ratio between init patch and this tone the same for you?

No, mine is very quiet. I have headphones and I'm having to push the OB-6 up to uncomfortably loud levels to hear anything from the lfo. It sounds like you have an issue.


Thanks and regards,
Dennis

Re: OB6 LFO bleed
« Reply #4 on: June 20, 2023, 07:03:34 AM »
No, mine is very quiet. I have headphones and I'm having to push the OB-6 up to uncomfortably loud levels to hear anything from the lfo. It sounds like you have an issue.
I'm on os v1.7.4 and I won't upgrade unless new functions are added.

W07

Re: OB6 LFO bleed
« Reply #5 on: August 15, 2023, 04:13:08 PM »
Not sure about the xmod thing, but have you also tried recalibrating the pitch and modwheel? i remember my out of the box P6 was slightly detuned and i could always hear a slight lfo modulation. Just recalibrating the wheels fixed that for me.

Re: OB6 LFO bleed
« Reply #6 on: August 29, 2023, 09:45:47 AM »
Yes, I tried calibration the wheels. Doesnít help. Sequential support says that the behavior occurs on all OB6s they tested in the lab. Not sure how it can be, that some people canít reproduce the issue.