LFO Question

[lesmizzell]

I'm currently working on a set of self-running drones. As I dig deeper into things...

A LFO is basically MONO, correct? So, if you set this up:

LFO1(square wave)--->OSC1 (freq)

...and then play a chord, all the notes will "march in sync" with each other, even if you stagger when you hit each note. Hopefully I'm not being an idiot here...

If you set everything on the LFO page up to basically make it a free running LFO, I was hoping that it would be "polyphonic" - each note played being modified from the LFO from a different starting position in the LFO wave. But, nope, all notes sync regardless.

The only way I've found around this so far is to add a small amount of key-track--->LFO1(freq). Just enough (around 10%) to make it slightly faster at the top of the keyboard and slightly slower at the bottom. Then all notes don't sync up, which is a totally different sound than everything being together.

Any other ideas here? Seems like a lot of trouble to have to add a mod routing to get a poly LFO. Or, am I blind and have just missed something somewhere?

[Hollow Sun]

lesmizzell said:

A LFO is basically MONO, correct?

No! There are separate LFOs for every voice

lesmizzell said:

So, if you set this up:

LFO1(square wave)--->OSC1 (freq)

...and then play a chord, all the notes will "march in sync" with each other, even if you stagger when you hit each note. Hopefully I'm not being an idiot here...

What is the RETRIGGER parameter set to?

If is set to NONE, then all voices will be affected equally as you describe (in this case, even though you have an LFO per voice, they are all behaving as on 'master' or 'mono' LFO). However, if you set it to KEY DOWN, the LFOs will retrigger for each note you play. That said, if you play a chord with all notes in it starting at the same time, they will be pretty much in sync. Also....

Even set like this, it's all to easy for you to pick up on the 'rhythm' of the modulation and play in sync with the LFO so it will appear that the LFOs are in sync. Try and avoid that temptation and deliberately play out of time with the LFO rhythm and you will have 'tumbling' LFOs with different notes going in different directions.

lesmizzell said:

If you set everything on the LFO page up to basically make it a free running LFO, I was hoping that it would be "polyphonic" - each note played being modified from the LFO from a different starting position in the LFO wave. But, nope, all notes sync regardless.

It will. If you have set it to be a free running LFO, it will (effectively) be mono and so all voices will be modulated in sync equally. The different notes may start at different points in the LFO's cycle but the mod will be uniform and synced.

If you want 'tumbling' LFOs, you should set KEY DOWN for RETRIGGER... but they will all be at the same rate.

lesmizzell said:

The only way I've found around this so far is to add a small amount of key-track--->LFO1(freq). Just enough (around 10%) to make it slightly faster at the top of the keyboard and slightly slower at the bottom. Then all notes don't sync up, which is a totally different sound than everything being together.

Yes. If you want 'tumbling' LFO that are asynchronous and running at different rates per voice, this is a way to achieve that (or you could use velocity)

lesmizzell said:

Any other ideas here? Seems like a lot of trouble to have to add a mod routing to get a poly LFO. Or, am I blind and have just missed something somewhere?

No - you're on the right track.

It might seem a palava but it's ultimately more flexible in the long run as YOU can dictate exactly how asynchronous you want the LFOs to be. Akai samplers (and other products) had an LFO DESYNC that did something similar with a switch but you had no control over it - it was either on or off. When ON, each voice's LFO ran at a slightly different rate to the others (subtle - hard to hear).


Steve

[lesmizzell]

[quote} However, if you set it to KEY DOWN, the LFOs will retrigger for each note you play. That said, if you play a chord with all notes in it starting at the same time, they will be pretty much in sync.

<...snip...>

Steve[/quote]

Yea - found it. Wasn't immediately obvious to me at first. But, it's working now.

Thanks!

I like to set up lots of little cross modulations in patches, even if they're just *barely* modifying something, to keep things from gettig too static. The LFO's running together were driving me nuts!

[Hollow Sun]

Glad to have helped


Steve

[lesmizzell]

admin said:

Glad to have helped


Steve

Thanks!

Now find me a way to modulate the arpeggiator clock rate through the matrix and we're cooking in aleatoric heaven!

[Hollow Sun]

lesmizzell said:

Now find me a way to modulate the arpeggiator clock rate through the matrix and we're cooking in aleatoric heaven!

Ha

No can do on that but for aleatoric mayhem, you should try employing the Sample+Hold - the rate of that can be modulated by anything in the matrix.... including its own source LFO so that as well as random pitch/tone/amplitude/pan, the rate is also random.


Steve

[mps]

admin said:

lesmizzell said:

Now find me a way to modulate the arpeggiator clock rate through the matrix and we're cooking in aleatoric heaven!

Ha

No can do on that but for aleatoric mayhem, you should try employing the Sample+Hold - the rate of that can be modulated by anything in the matrix.... including its own source LFO so that as well as random pitch/tone/amplitude/pan, the rate is also random.Steve

For the explanation of what the heck these guys are talking about I found it here...
en.wikipedia.org/wiki/Aleatoric_music

And so Steve is quite correct about the sample+hold ( now that I know what aleatoric means) .

That is one of the things I love about the Club. I learn something new here nearly every day.

[lesmizzell]

... but for aleatoric mayhem, you should try employing the Sample+Hold

If any of you have experience with a real modular, then you know the cool stuff you can do with a S&H module.

In its most basic form, a modular S&H has a "sample" and a "clock" input, and a single output. When a trigger signal is received at the "clock" input, the circuit "samples" the voltage level at the "sample" input, and holds that voltage until the next clock trigger is received. This voltage is present at the "output" jack.

Most of today's KorYamaland keyboard synths use a dumbed down version of S&H. The "sample" input is fixed at noise - so the output is just a random signal that changes at the clock rate.

But, a S&H can do far far more than generate random signals, and the Fusion has gotten it right, since the input signal can be any waveform coming from a LFO.

Here's some fun stuff to experiment with for starters:

Set the S&H to control "pitch" so you can clearly hear what's happening. Once you get it down, you can use this to modify a ton of different things.

If the LFO wafeform is set to random (noise), then you get the classic "random" series of notes. Fun controlling pitch, filter cutoff...

But...

If the input LFO waveform is a slow sine wave, careful adjustment of the S&H clock rate will yeild a steady up/down scale. Varying the LFO rate and S&H clock rate will give you all sorts of different scales to play with.

Change the LFO to a saw wave, and you can generate an ascending scale...and so forth.

Get the S&H clock ratio just right to the LFO rate, and you can generate all sorts of parellel scales, chordal cascades of notes...

Since the Fusion will allow you to modulate the S&H rate clock, you can really get creative stuff like scales that speed up as they rise in pitch, wild random rhythmic structures ... and once you get into higher clock rates, really strange noises, weird filter responses and all sorts of stuff!

...and I haven't even looked into using a table to modify the S&H response yet!!

My only "wish" here would be to have *any* sample in the Fusion available as a LFO waveform. Can't have everything though, huh?

Maybe a future update? While they're at it, maybe they'll add granular functions to the OSC's and let me use the sampled waveforms in the FM section as well. (Fingers crossed)

Meanwhile - happy tweaking!

[Hollow Sun]

lesmizzell said:

If any of you have experience with a real modular, then you know the cool stuff you can do with a S&H module.

For anyone interested in Lez's description of S&H, this is covered in detail in the Alesis analogue synth tutorial - 'Introduction To Analog Synthesis' HERE.

Lez is spot on - most other synths offer very little in the way of S&H weirdness (unless silly cliched computer noises are your bag!). Fusion's implementation of S&H approaches (and maybe exceeds) that of the big, old modulars and much fun can be had if you are into true electronica.

Good to see some fellow 'aleatorists' here!!!


Steve

[Hollow Sun]

mps said:

For the explanation of what the heck these guys are talking about I found it here...
en.wikipedia.org/wiki/Aleatoric_music

And so Steve is quite correct about the sample+hold ( now that I know what aleatoric means) .

I am a huge fan of aleatoric or 'stochastic' music - where there is a random element beyond your control.

A lot of music is made using pre-ordained rules. Classical music in particular prescribes to rules (no consecutive 5ths, few consecutive thirds, relative key modulations, end in a cadence, whatever). As does blues-derived rock music ... the use of the I, IV, V chord progression, for example, that is the basis of much of rock and pop ... or the I, relative minor, IV, V as almost defined in Pachelbel's 'Cannon'. Both of these are the backbone of -- I reckon -- 80% or more of popular music these days.

But people break away from this ... Debussy's 'Claire De Lune' is very 'modal' with it's heavy use of consecutive 5ths and, I suppose, Jazz is aleatoric and stochastic in that the composer provides the basic framework and the musos blow over this. Later, of course, in the extended guitar, etc., solos of rock music.

Of course, serendipity is also a major force behind music creation - i.e. going from one chord to another that kind of shouldn't be allowed or is a mistake but sounds good and is exploited.

But electronics takes all this into a whole new area. You (the composer/programmer) set some basic parameters but the interaction of those parameters sets 'the machine' off in directions you might not have imagined creating evolving and undulating patterns that you (as 'composer') could never have imagined or forecast. As the 'composer', you have some control over the amount of stochasticism through the settings of the parameters but you are also at its mercy. And interacting S&Hs is a way to achieve this. And serendipity is involved. Two problems exist however:

¥ It cannot be notated and repeated in a performance - it is unique to the moment - and....

¥ It is -- almost by default -- atonal and 'soundscapey' and 'sci-fi', whatever ... which is not everyone's cup of tea. Also...

¥ You are unlikely to get a hit record or a profitable publishing deal from it!!!!

But it fascinates me nonetheless.

I have some keyboard chops and my feet will tap to a good groove (I've been known to actually dance on occasions!) but a strong part of me wants to explore the random, evolving textures of aleatorism or stochasticism where you set down some basic 'rules' or parameters and let 'the machine' create the output.

For this, apart from the big modulars of old or new, nothing can touch Fusion for this kind of stuff. In fact.... here's a thought....

Maybe Fusion shouldn't be called a 'synth' or a 'workstation' ... maybe 'electronic music studio' might be a more appropriate description.

Hmmmm - I like that ... although I imagine that would be a difficult concept to sell these days for the marketing and sales people ..... or would it?!


Steve

[gwenhwyfaer]

One could almost call it "a synthy EMS"...

[lesmizzell]

For those interested, Cyndustires (makes Modcan format modules) runs an annual "Aleatoric" composition contest.

Not all music entered could exactly be called "aleatoric", but listening to entries is darned fun.

This years contest just ended:
www.cyndustries.com/bugmusic_entries.cfm

Here's the 2005 entries:
www.cyndustries.com/bugmusic_vote_completed.cfm

There's a very wide mix of gear represented here - from Serge and Buchla modulars, to Roland Juno's, MAX, Supercollider and Ableton Live - you name it, somebody used it.

Enjoy!

[mps]

I have made quite a few experiments in this area. Some sound better than others. As soon as i figure out a hosting situation I will post a couple of them.

Many years ago I was involved in project where there was a random element outside of the bands control. His name was Chuck and he played the bass.

[lesmizzell]

admin said:

mps said:

You (the composer/programmer) set some basic parameters but the interaction of those parameters sets 'the machine' off in directions you might not have imagined creating evolving and undulating patterns that you (as 'composer') could never have imagined or forecast.

The thing that makes this great to do on a modular are various modules that generate triggers based on input:

To list a few:

Comparators
Logic modules
Envelopes that generate a trigger at the end (and can therefore loop)
Burst Generators (http://www.cyndustries.com/modules_burstgen.cfm)
Pulse Dividers
…and so forth

So, with careful programming, you can "generate" a piece of music with "form". A number of events are patched to run, and then at the event end a trigger is generated to set off a different set of events, and so forth.

As great as the mod matrix on the Fusion is, this sort of thing gets tough to set up. I would really like to be able gate/trigger an envelope from a source in the matrix. This single addition would open up a world of possibilities in generating what has gotten dubbed "noodle" patches in the Nord Modular world. The community that grew up around the original Nord Modular took great delight in seeing who could program the most complex, longest-running without-repeating noodle, and you'd have to hear some of the creations that were patched up to believe them.

This sort of thing is going to be interesting to try and accomplish on the Fusion. It's easy enough to set up a "chaos" patch by routing only 1 osc, 3 lfo's, and a filter. Try this (you'll see why it's called "chaos"!):

1. LFO1--->LFO2 (rate)
2. LFO2--->LFO3 (rate)
3. LFO3--->LFO1 (rate)
4. LFO1--->OSC1(frequency)
5. LFO2--->Filter Frequency

Start playing with the LFO waveforms, rates, and amounts of modulation and see what you get.

As for modular-like events, things are going to be tougher. I'm still working out methods, but for example, to make up for the lack of trigger and event generators, the Fusion's arpeggiator is going to have to perform multiple functions. This has limitations though, as the arpeggiator clock rate is not available as a modulation destination. I'd also like to be able to switch the arpeggiator on and off through the matrix, but no can do. Still, between being able to modulate the S&H clock, combined with the arpeggiator, I'm looking forward seeing what I can come up with.

Perhaps in the future we should have a "noodle patch" contest!

Happy Patching!