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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
 

https://Soundcloud.com/wavescape-1

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 »

mosen

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:



Re: LFO's out of sync (with WAVE RESET ON)
« Reply #4 on: May 29, 2020, 09:42:45 AM »

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?

Can't speak for the Pro-3 but I can confirm that the Prophet 12 has this bug, see here: https://forum.sequential.com/index.php/topic,2011.0.html

It basically makes syncing LFOs useless, and really prevents it from doing any rhythmic LFO stuff. I find that setting the LFO phase to ~105 is sort of a workaround. Of course there is an artifact when first triggering the note, since it's starting at the wrong point of the cycle, so it's a pretty crummy workaround, but works okay for things like long sustained sample+hold patches.

I doubt this is being fixed but I really hope it will be, it's an obnoxious bug.

Re: LFO's out of sync (with WAVE RESET ON)
« Reply #5 on: October 12, 2020, 07:46:33 AM »
Okay, now that the Pro 3 is out for a while, can anyone confirm if the problem still exists on the 3?

I'm interested in the 3 but if it can't reset the LFO wave sync start correctly to the MIDI clock (like the Pro-2 does now), I will not buy it. I need my synths to have LFO's that always start correctly and in sync (so no just BPM sync, but also a saw LFO starting ON the beat every time the MIDI clock starts). If the 3 doesn't do this, I'm more interested in the Peak to be honest as that one doesn't have this annoying bug.

Honestly, I don't understand why there not more people commenting on this? It's bugging me so much.
How do you deal with this? Or do you only use un-synced LFO's? The internal sequencer doesn't have this problem so that's the only solution. It's just impossible to have a 1/4th LFO with saw / square / ... wave to beat in time with MIDI clock. Yes, the speed is correct but it's just impossible to also have the start point of the saw wave to start correctly on the beat.
A modern synth should be able to have LFO's beating in sync and in time (so starting in time) with MIDI clock, no?

« Last Edit: October 12, 2020, 07:49:33 AM by Sarrova-Q »

Re: LFO's out of sync (with WAVE RESET ON)
« Reply #6 on: October 15, 2020, 10:46:16 AM »
Sarrova,  Its a valid question why nobody is noticing,  but maybe there's only a small percentage of the users using in the fashion that you are?  I mean,  I never noticed it, but I'm more likely to let LFOs go free running for the kind of stuff I like doing.  But then again I'm like always in a fog apparently when it comes to discovering bugs.   Like when you read the bug reports on updates, I'm like , hey, never noticed any of that  ; ???
DSI Equipment: Poly Evolver Keyboard, Evolver desktop, Prophet 8,  Pro-2, OB6, P-12
 

https://Soundcloud.com/wavescape-1

Re: LFO's out of sync (with WAVE RESET ON)
« Reply #7 on: October 16, 2020, 01:21:27 AM »
Sarranova, a while back i also struggled with this. I wanted to use the pro 2 as a metronome using a short lfo pulse to mute and unmute the level of an oscillator. I tried setting the phase different, delaying it with an envelope and so on, but it never quite worked the way i wanted! So i feel you. I also posted about it on this forum. Cant quite remember how the conversation went there, but yeah.... The post was called "using the pro 2 as a metronome" or something like that.