Slow down Voyager LFO and other tricks

parallel98 · Post by **parallel98** » Sun Feb 29, 2004 5:23 pm

Hi, here's some tricks and questions:

---Slow down the Voyager's LFO by modulating it with itself:

1) Connect the LFO output on VX351 to the back panel Mod2 input
2) Mod one bus: LFO modulates Filter or Pitch, full amount
3) Mod two bus: on/Mod2 modulates LFO
4) LFO Rate .8HZ or below
5) Wheel up

The LFO is now much slower and good for very slow filter sweeps, etc. This modulation routing may also be possible with the new Pot Mapping function in OS2, but I haven't tried it. Also if you use a mult and send the triangle LFO output to both the LFO rate input and MOD2 input you can get even slower frequencies that are barely noticeable. Also notice the frequency of the LFO increases the farther it rises above zero, and decreases the lower it gets below zero. Can anyone explain why? I can't.

---Speed up LFO to audio frequencies

Same setup as above, but unpatch VX351 from the back panel, turn LFO rate to 12 HZand above

---Staircasse modulation:
The manual implies you need the VX and CP for this, but I found you can modulate the LFO with the sub-audio pulse wave of OSC 3 to get a nice staircase modulation:

1) Mod 1 bus: LFO triangle modulates Filter cutoff
2) Mod 2 bus: Osc3 modulates LFO
3) Osc 3: lo freq, 32', thin pulse wave
4) mod wheel up
5) experiment w/amount on both mod busses and Osc 3's wave form to get a really nice staircase mod. Thin pulse yeilded the best results for me. Also, once you get it the way you want, adjust the spacing so one side is a step ahead or behind the other side.

The above examples make me wonder exactly how the LFOs are interacting? On my Sidstation I can "lace" one LFO with another to get complex wave forms, and I can also "add" LFOs together. What's the difference? What does the resulting waveform look like if you mix 2 LFOs on the CP's CV mixer?

Another question regarding the Voyager's newfound ability to send MIDI CCs:

When I apply a CV to the MOD 2 input on the Voyager's back panel, the Voyager starts sending MIDI data. The data appears to be in sync with the CV (for example, when I apply the LFO CV from the VX's LFO output), but it also seems to disappear when the CV swings below 0. At first I thought that the OS2 Voyager would automatically send the CC data of whatever control was being modulated by a CV, but when I recorded the CC data it appeared not to match the new MIDI CC spec. For example, I found that when I modulated the pitch with the LFO, the Voyager sent CC4 and CC36. 4 is the CC# on which Voyager receives LFO rate info, but neither 4 or 36 are supposed to be sent by the Voyager according to the new OS manual. Any ideas?

chihuahuaphile · Post by **chihuahuaphile** » Mon Mar 01, 2004 4:54 am

There is another way to slow down or speed up the LFO rate without the use of the xpander or pot mapping.here is how.

To slow the LFO rate down:

1. set the petal/on bus source to OSC3.
2. set the petal/on bus destination to LFO/PGM (make sure that the LFO RATE in the edit/petal dest. menu is selected)
3.set the petal/on bus amount knob fully clockwise
4.turn all the OSC3 knobs fully clockwise.
5.flip the 3KB CONT switch to "OFF"
6.flip the 3 FREQ switch to "HI"

To speed the LFO rate up:
use the same settings as above except turn the OSC3 WAVEFORM to square wave.

For added control over LFO rate use an EP-1 Expression Pedal into either the MOD1 or LFO rate jack on the rear panel. you can also of course use this same set up on the mod wheel bus and use the mod wheel to control the rate.

Randy

parallel98 · Post by **parallel98** » Tue Mar 02, 2004 9:04 pm

This works really well but I don' t understand why. It's basically modulating the LFO with a very high freuquency pulse wave, correct?

chihuahuaphile · Post by **chihuahuaphile** » Wed Mar 03, 2004 4:37 am

i only have a rough theory as to what is actually happening.
i believe that ,in this case, the pulse wave is interupting the LFO's rate.thus slowing it down.you get different effects with different waveforms against certain octaves.i've made some unbelievible staircase generators to really crude arppegiators modulating the LFO with different sources.very fun stuff! i can't imagine what i will do when i finally get ahold of the CV Xpander.

Randy

parallel98 · Post by **parallel98** » Wed Mar 03, 2004 1:45 pm

Yeah, that seems like a feasible theory. The interesting part is that as you turn the octave of OSC 3 to lower frequencies, the LFO rate increases. Also your patch does not make the LFO frequency increase as it rizes above zero, which makes it very useful. I've also tried to modulate the LFO w/Osc 3 a lot and get very unpredictable effects that I can't quite rationalize.

I have to CV outs and they're great, but honestly the OS2 Pot Mapping functionality (which is esseintially a powerful modulation matrix) makes them kind of obsolete unless you are patching to other analog gear. I am looking into the fooger control processor for the extra LFO.

Geoff

jamirokid · Post by **jamirokid** » Sun Jun 24, 2007 7:37 am

How would you slow the LFO down with potmapping? I have 3.1.
Josh

GregAE · Post by **GregAE** » Sat Jun 30, 2007 12:47 pm

jamirokid wrote:How would you slow the LFO down with potmapping? I have 3.1.
Josh

In Pot Mapping, I suppose you could assign the Pitch or Mod Wheel to the LFO Frequency (Rate) parameter, and set the direction to Inverse and the Amount to a non-zero value. This would give you dynamic control of the LFO frequency via the wheels (slowing the frequency as the wheel position was raised), but I don't know how useful this configuration would be in practice. Also, it would not slow the LFO below its normal range if that's what you're trying to do. You'd need to apply an external CV to do that.

On a somewhat related note, there are some CV routing diagrams available on MoogSpace that illustrate how to mess with the LFO Rate using feedback techniques (using a Voyager and VX-351). This technique actually warps the shape of the LFO wave by playing with the rate. You can find these diagrams (and some sample audio) here:

https://www.moogmusic.com/members/?sect ... ile_id=268

https://www.moogmusic.com/members/?sect ... ile_id=263

https://www.moogmusic.com/members/?sect ... ile_id=269

- G

jamirokid · Post by **jamirokid** » Mon Jul 02, 2007 3:23 pm

Thanks Greg. If I got the CP-251 could I use the invert on there to slow the LFO down slower than the knob fully CCW? Is that what a signal iverter would do or am I missing the point?
Josh

GregAE · Post by **GregAE** » Tue Jul 03, 2007 4:45 am

jamirokid wrote:Thanks Greg. If I got the CP-251 could I use the invert on there to slow the LFO down slower than the knob fully CCW? Is that what a signal iverter would do or am I missing the point?
Josh

Hi Josh,

An inverter simply inverts the phase of a signal, nothing more. An inverter would have no effect on the LFO other than flipping the waveform by 180 degrees.

The inverter in the CP-251 is actually part of the Mixer module. Although the inverter can't reduce the speed of the LFO, the Mixer features an Offset control that can be used for this purpose. The Offset control provides a steady state CV at the Mixer output, and this CV can be positive or negative. If you route the Mixer's output to the Voyager's LFO Rate jack, you can use the Offset control to provide a negative voltage that would slow the LFO rate below the lowest setting of the Voyager's LFO Rate control. (Note: The CP-251 also has an LFO, and you can use the same Offset configuration to make it run VERY slowly.)

Yet another reason to own a '251.

--G

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Slow down Voyager LFO and other tricks

Slow down Voyager LFO and other tricks

why does this work?