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LFO's out of sync (with WAVE RESET ON)

LFO's out of sync (with WAVE RESET ON)
« on: May 11, 2020, 08:41:31 AM »
My Pro 2's LFO's are out of sync.

I figured out that the problem lies within the "wave reset" function of the LFO's. If that is on, the LFO misses a few milliseconds in the first cycle. I need it to be ON to make the LFO's sync to another clock.
I can clearly see this bug in recorded audio. The midi note is on the beat, then the first LFO cycle is a bit too short so when the following cycles start they're all too early on the grid (but have a correct timing when moving the audio).

I contacted Sequential, and this is confirmed as a bug.
My question is if anyone knows if this is currently being fixed for the next firmware update?
Is there anybody able to sync his Pro 2 LFO's to another clock so they start correctly in time?
Because of this bug, the LFO misses some milliseconds and all the cycles of a wave are too early.

I just can't use my Pro 2 like this and I'm seriously thinking of selling it because of this. Do the Pro 3 or Pro 12 have this problem too?

Re: LFO's out of sync (with WAVE RESET ON)
« Reply #1 on: May 11, 2020, 01:26:28 PM »
I CAN use my Pro 2 like this evidently,  as I never even noticed it ;)  In all seriousness though, depends how you are recording, but you could add some latency purposefully.
DSI Equipment: Poly Evolver Keyboard, Evolver desktop, Prophet 8,  Pro-2, OB6, P-12

Re: LFO's out of sync (with WAVE RESET ON)
« Reply #2 on: May 12, 2020, 01:30:56 AM »
Nope. Adding Latency doesn't work because of two reasons:
it's only the first cycle of the LFO's that is too short.
the MIDI notes will move together with the LFO.

In the image below you can see this problem. LFO is set to Filter Cutoff, wave reset ON.
The note starts on the beat at 1.3, but because the first cycle is too short with wave reset on, the second cycle of the LFO (8ths speed) comes in too early (the highlighted part).
All the other cycles are in the correct tempo (but shifted in time because of that first cycle) and because of that there's even a 5th cycle starting (at the end, before midi bar 2) before the following midi note drops.

The timing doesn't feel right, you can clearly hear this. Try sequencing your Pro 2 from another sequencer, DAW or hardware doesn't matter. Set up some 4th or even longer 1/2 notes exactly on the beat and assign a sawtooth LFO to cutoff with 1/8ths speed. Make sure Wave Reset is ON, you want to start the LFO exactly together with the note. Maybe add a little Envelope attack to the filter to accentuate the start of the note. You can hear double attacks of the filter because the LFO speed is shifted (remember the first cycle being a little bit too short) and it will already start another unwanted cycle just before the next note comes in. Because of the Envelope to the filter, you can hear this clearly when the note starts. Layer this with another synth doing the same, or record it if you really can't hear this. It's more than obvious and feels very sloppy and ... well just un-synced.

« Last Edit: May 12, 2020, 01:46:09 AM by Sarrova-Q »


Re: LFO's out of sync (with WAVE RESET ON)
« Reply #3 on: May 12, 2020, 08:58:14 AM »
After reading your post i tried it for myself and yes, there is some inconsistency on my LFO sync as well.
I did a simple 1 note sequence, with a saw lfo (wave reset on) modulating the filter cutoff 1/8th note as well as a fast attack env.
While the first bar is fine, the second bar gets sloppy - see here: