Time synched FX, placed correctly on the beat?

Dr. Dipwad

Experienced
I'm convinced that the Axe FX II is what I need, and am waiting on my coupon link.

That said, I wonder: Does even the Axe FX II solve the problem of keeping time synched modulation effects properly placed within the beat?

What I mean is this: Let's say you have a song played at tempo 120, and you want a saw-wave tremolo (or something) where you hold down a chord and hear the highest point of every wave form perfectly in synch with the hi-hat.

This will generally work for the first few beats, but then a subtle difference in tempos between your (perfectly robotic) FX unit and your (excellent, but only human) drummer will cause a bit of drift. (It's not that the drummer changed tempos; he's still at 120, but maybe he was at 121 for a split second because he rushed a fill or whatever.)

Before you know it, the top of your saw-wave is hitting at the midpoint between your hi-hat strikes. Musical badness results. Yet the problem is not that your tremolo is at the wrong tempo: It's at 120; the drummer is at 120; but the cycle is now starting at the wrong point relative to the downbeat of a measure.

So there isn't any misunderstanding: I'm not asking about mere tap tempo. I know how that works; I'm asking about something that would help the Axe II adjust where the start of a tremolo cycle (or arpeggio pattern, or whatever) falls.

As I await my Axe FX II, I'd like to know...

Does the Axe II have anything to help the guitarist keep adjusted to the drummer? Like, I dunno...detecting strums and using that to figure out where the beat is, and automatically keep the tremolo in synch with that?

Or is this something even the Axe II technology can't make easier?

(Sorry if this is a dumb noob question; I tried searching the forums but wasn't sure what search terms to use for such a complex and specific question.)
 
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A switch or ADSR can restart the control menu LFOs with each press/trigger. With the switch method you could have a separate switch or (possibly more helpful) set the tap tempo switch to also restart LFOs.
 
This is only an issue if your FX never decay. There may be some cases where that's what you want, but IMO it's extremely rare (and it clutters the mix in a hurry). If your FX decay at all, there will be no cumulative timing error.

On the other hand, if your drummer's any good, he'll be listening to the guitar's automated tempo, and he'll adjust if things start to go astray.
 
A click doesn't really address what he's asking about, unless you send it from a DAW/sequencer along with CCs to reset the Axe LFO occasionally.

Consider playing with no click and activating a quarter-note square tremolo in the middle of a song. By tapping the reset/tempo switch a few times before engaging the effect you'll get the correct tempo & LFO phase. Not doing that could mean the pulse you want on the beat ends up on the upbeat or anywhere else. Matching the tempo alone isn't enough because the LFO alignment will be random.
 
a little different approach, but conceivable with the Axe would be to use it as the infamous pumping Techno compressor.
feed it a signal from the drumkit (kick?) and assign this to the sidechain of the compressor.
set the compressor really aggressiv sounding (fast, hard and lots of gain reduction).
now everytime the kick comes in, the guitar signal gets squeezed.
by finding musical sounding attack and release times you'd get some type of time synced duck effect.
always in time, since the drummer controls it.

p.s.
I just remembered that there was no way to mute the sidechain signal (Gen1) was this changed?

p.p.s.
could a signal from the drumkit somehow be used to re-trigger the LFO/sequencer?
 
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I use the same approach as bakerman. I have an LFO that is set to trigger with an envelope.
so it resets it when I breifly mute the strings or start a sections.

This ensures that you start the lfo in the same place every time as well.
 
A click doesn't really address what he's asking about, unless you send it from a DAW/sequencer along with CCs to reset the Axe LFO occasionally.

Consider playing with no click and activating a quarter-note square tremolo in the middle of a song. By tapping the reset/tempo switch a few times before engaging the effect you'll get the correct tempo & LFO phase. Not doing that could mean the pulse you want on the beat ends up on the upbeat or anywhere else. Matching the tempo alone isn't enough because the LFO alignment will be random.

Bakerman is spot on here, as usual :)

That's exactly how I do it:
1. Patch one, clean guitar, tempo set to global. Approaching the end of the given song part, I set the tempo by tap footswitch
2. Patch two, Recto with tremolo in 16th note pulse, global tempo - so it keeps the tempo I tapped in from the prior patch. The tremolo is sync'ed to LFO1 (which is set to 16th notes) and the LFO "run" is tied to the envelope controller; this makes the LFO start at the first strum, so the pulse is in time with the beat.

As said, if envenlope/ADSR is not an option, you can always retrigger the LFO by a switch.
 
I'm about to start reading through the replies, but before I got into the weeds asking follow-up questions, I wanted to say up front:

Thanks, everyone, for responding!
 
Okay, initial responses-to-responses:

1. Zonk: Let's say I want the tremolo to produce one saw-wave per 16th note at tempo 120. I think if I tried to rock the volume manually with an expression pedal that fast, my foot would fall off! (And tremolo was only an example; I'm looking for a solution that would apply equally to sequenced arpeggiation and filter effects.)

2. Bakerman:
That sounds like it might be what I need...if I understand you correctly. I think I need to read up on it, but it sounds like you're saying that:

(a.) I can have modulation controlled by an LFO;
(b.) I can have the LFO synched to the global tap tempo (at some note-value subdivision; say, dotted eighths)
(c.) I can have a footswitch set to restart an LFO;
(d.) If the LFO is running a little fast or slow relative to the drummer, a single tap on a downbeat should restart its cycle, thus re-synching it with the down-beat;
(e.) I can even make the tap-tempo footswitch double as the LFO-starter, so that my last tap will determine the start of the cycle going forward.

Did I get that right? And, regarding (e.), if things start getting out-of-synch a few measures later and I press the tap-tempo footswitch once to get the cycle start-time back in synch, don't I risk the tempo changing unintentionally?

3. Rex: Well, the drummer's good, but that doesn't mean the onstage monitor mixes are consistently worth a frog's fat fanny. I get the impression he can barely hear me when I'm on a rhythm patch, half the time.

As for whether the effects decay...am I missing something? That doesn't seem, to me, to solve the problem....

Let's say that I strum a chord at the moment that the drummer arrives at the down beat, at tempo 120. Meanwhile the LFO is churning away at tempo 120. I might be lucky and find that my downstrum, and the drummer's downbeat, happen to arrive at the same moment that the LFO's cycle is at the very beginning. So I let it decay...but four bars later, when the drummer's downbeat hits again and I downstrum again, I find that the LFO is now no longer quite in synch, and my downstrum now lines up a bit later than the start of the cycle. It might, for example, be in the "trough" of a saw wave tremolo, instead of at the "peak." The result will be a sort of whup-whup-whup effect instead of a pow-pow-pow effect, because they're out of synch.

So, in fact, the decay of my strum is part of the problem: As the sound gets softer and softer over a couple of measures, the ability of the drummer to hear it in the monitors grows less and less, and by the time the next strum comes around, it's been too soft for him to hear for awhile, and he may now be slightly ahead of or slightly behind the LFO.

4. Matt R: Yeah, sorry, a click is not really an option here, and wouldn't matter anyway unless it was coming from a sequencer that could simultaneously feed a MIDI timecode or some such stuff into the Axe II, to ensure the LFO is perfectly in sync with the click.

5. Bakerman: Oh, lookit that, you just said exactly what I just said to Matt R. Maybe I should have read the whole thread of responses in detail before I started replying to them in order!

6. DonPetersen: Huh. Not really what I was looking for, but an interesting thought. I didn't know you could do that.

7. JavaJunkie: Got it. More validation of the Bakerman solution, which looks like the best approach.

8. Sebastian: Aaaaand yet more validation of the Bakerman solution.

It looks as if I need to go spend some time with the Axe II FAQ section on ADSR and LFO stuff, to wrap my brain around what Bakerman said a bit better. And I'm sure practice makes perfect; once I actually have my Axe II, I'll need to try it for myself and figure out how to really program this into a patch.

Thanks again, everyone, for your input!
 
it sounds like you're saying that:

(a.) I can have modulation controlled by an LFO;
(b.) I can have the LFO synched to the global tap tempo (at some note-value subdivision; say, dotted eighths)
(c.) I can have a footswitch set to restart an LFO;
(d.) If the LFO is running a little fast or slow relative to the drummer, a single tap on a downbeat should restart its cycle, thus re-synching it with the down-beat;
(e.) I can even make the tap-tempo footswitch double as the LFO-starter, so that my last tap will determine the start of the cycle going forward.

Did I get that right? And, regarding (e.), if things start getting out-of-synch a few measures later and I press the tap-tempo footswitch once to get the cycle start-time back in synch, don't I risk the tempo changing unintentionally?

Yes to all. For (e.) a single tap won't change the tempo if it's been more than 2 seconds since the previous tap. It's assumed to be the start of a new series, and the next tap would change tempo. The Axe averages times between up to 10 taps (or maybe it's 11 taps, 10 total intervals) if you keep tapping. So if you find there's often a need to resync soon after setting one tempo, a better approach would probably be tapping throughout those few measures. That way you wouldn't risk having a scenario like setting one tempo, realizing drummer settled into a slightly different tempo, noticing LFO drifting & wondering if it's been 2 seconds yet. You could also have the LFO reset on both the tap switch plus another switch by itself, if your controller allows more than one CC per switch.
 
I think Bakerman is closer to the solution you're looking for than I am.
 
Ok, I'm trying to set up something like this right now but I'm running into trouble. Not sure if I'm doing it right.

I want to have an "auto-wah" that is synced to the tempo (8th notes). I want to be able to restart the lfo cycle via the envelope controller. Right now I have LFO 2A set to control the "Controller" parameter of the wah block. So good so far. Then in the LFO 2 controller itself I have the Envelope controller controlling the Run controller.

Now, the envelope controls RUN just fine. The problem is that when RUN stops, the LFO stays at whatever position it stopped at. Then when it starts again, it starts from that same position that it stopped at. I want it to reset to zero when it stops (or starts) so that it always starts at the beginning of the cycle.

Can anyone tell me what I'm missing? Is this possible? Should I do this a different way? I could really use this effect for a bunch of songs.
 
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(Bump)

I bet Bakerman understands this one. He seems to have this part of the axe well within his understanding. Bakerman? Anyone?
 
From the description in the manual, the Run and Tempo parameters seem to conflict. It doesn't come right out and say so, but each seems to want to do different things to the LFO waveform, depend on what's going on at a specific time.

Also from the manual:
Tip: An LFO that is locked to tempo can still “drift” from another system or device. To stay locked to “song position,just stop and restart periodically from your DAW/sequencer with a quick pair of OFF/ON messages sent at regular intervals.

Reading between the lines again, it would seem that if you can program your MIDI pedal to send a rapid Off-On command sequence, you may be able to keep the LFO in time with an occassional tap of a footswitch.
 
Now, the envelope controls RUN just fine. The problem is that when RUN stops, the LFO stays at whatever position it stopped at. Then when it starts again, it starts from that same position that it stopped at. I want it to reset to zero when it stops (or starts) so that it always starts at the beginning of the cycle.

Can anyone tell me what I'm missing? Is this possible? Should I do this a different way? I could really use this effect for a bunch of songs.

This doesn't happen on the Ultra. Did you verify that the wah ctrl dot is actually stopping at various positions? Not just something different from what you're expecting--for example, the "A" version of a sine LFO begins on the rise from 50%.
 
@Rex, yeah, I couldn't see a clear way to do this based on those docs. I guess I'm just hoping it's possible.

@Bakerman, yes I did see the dot stopping at random locations. So maybe this does work differently on the Ultra. This would be such a killer feature, I'm surprised no one else is using it on the Axe-II.

Thanks so much for the replies. I love this forum.
 
@Rex, yeah, I couldn't see a clear way to do this based on those docs. I guess I'm just hoping it's possible.

@Bakerman, yes I did see the dot stopping at random locations. So maybe this does work differently on the Ultra. This would be such a killer feature, I'm surprised no one else is using it on the Axe-II.

Thanks so much for the replies. I love this forum.

I think it must have changed - bug or intentional. I'm pretty sure it was working when I set my boulevard of broken dreams patch up. It certainly isn't now. IMO is should restart the LFO, that was the main point of it when we asked for the feature.
 
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