LFO, VCO, VCA

Forum for JUPITER-80
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marctronixx
Posts: 187
Joined: 01:39, 16 September 2007
Location: Los Angeles

LFO, VCO, VCA

Post by marctronixx »

It's no secret the Jupiter 80 intimidates me.

the main reason? not fully understanding how VCO, LFO, VCA, LFO mod, etc relate to each other. I know what the acronyms stand for and know what they mean on their own, but i am still aloof as to how to best use them.

there are a billion videos on keyboard synthesis.

Can someone recommend a jupiter-8 website or video that demos these parts and how they affect one another?

or even a generic video or website that talks about these parameters and how to best use them?

one of my main reasons for getting 3 jp08s is so that I can get hands on with how the jupiter works in creating sounds from its parameters, all whilst sitting at my desk.

I guess i need to know synthesis theory? I used to have a dx7II FD and after a while I got pretty handy with it. but the jupiter is a different beast.

other than going to school and just being born with a keyboard in your mouth, :) how did you best get to grips on VCO, VCA, PWM, VCO MOD, etc...?

Thank you for taking time to read and respond. I am well aware I am not as keyboard savvy as the majority of pros on here, and its not my intent to ask dumb questions.

For reference, I DO have a Juno 60 (since 1987) and I am well versed/super comfy in how it works, but the jupiter 80 (and 08/8) are a much different beast on the front panel...

Marc
Los Angeles
realtrance
Posts: 128
Joined: 16:39, 8 April 2005

Re: LFO, VCO, VCA

Post by realtrance »

How deep do you want to go? Curtis Roads' "The Computer Music Tutorial" is definitive, but huge.

I'm not much on YouTube video instruction, but Search on Synthesis Basics and I'm sure you'll find something.

The simplest thing I can say here is: there is tone. And there is modulation of tone.

VCO creates a static tone. VCA amplifies it. LFO and envelope modulate it. LFO modulates it by varying pitch, or filter, with periodicity, sine wave being simplest. Envelope modulates it via Attack (note on) Decay (decay of pitch, volume or filter, depending on whether envelope is controlling tone, amplifier or filter cutoff/resonance, Sustain (some setting lower than full on, or decay will have no effect) and Release (how long it takes for note to stop sounding after Note off, release of key.

You forgot VCF. That is also a modulator of tone. LFO and envelope modulate IT. So when you apply LFO or envelope to Filter, you are modulating the modulator. That's where the magic starts. :)

If you've had a Juno-60 since 1987.... you should basically understand the Jupiter 8/JP-08. It's just a slight (but important) variation on the same basic architecture. The key thing when using two-osc per voice -- which is what differentiates the -8 from the -60 -- synths, is that each oscillator can be set to a different frequency. If you choose intervals -- 4ths, 5ths, 7ths, 12ths, that sort of thing -- you get two tones. If you choose subtler differences in frequency, you get the origins of the so-called "Supersaw" concept: two sawtooth oscillators, in this case, with the frequency differences subtle enough that it causes slight "beating" between the frequencies, producing a "strings"-like sound.

All the JP-80 is, in the synth department, is the same, basic concept but with many multiples of that one, two-osc synth.

Hope that helps.
Macska
Posts: 305
Joined: 06:34, 28 July 2013
Location: Oklahoma

Re: LFO, VCO, VCA

Post by Macska »

It's not as bad as the intimidation presents itself to be. The trick is to start simple and then add more when you start wishing there was more to edit. The Juno 60 is good practice because it's the same type of synthesis as the JP 80. Think of your JP 80 as like, what, 36 Juno 60s all chained together lol.

VCO - The Sound
VCF - A Mouth that shapes the sound
VCA - The Volume of the sound
LFO - Little elves that turn knobs automatically.
Envelopes - How the VCF and VCA act.

Now on the Jupiter make a preset that is only 1 part - the supernatural synth. Everything else is turned off and it's only 1 part! No layered parts here.

Turn off two of the partials, and play around with only 1 partial. That right there is pretty much the same thing as your Juno 60 and you should feel at home. Leave out the PCM option for OSC, and don't worry about the other options like Unison and stuff for now. Just make some simple single oscillator patches.

No amount of tutorials are going to turn on the lightbulb, the more time you spend with the system the more familiar you'll be. Enjoy!
realtrance
Posts: 128
Joined: 16:39, 8 April 2005

Re: LFO, VCO, VCA

Post by realtrance »

Yes I like that, except it helps also to think of an envelope as another little elf that, instead of turning the knob repeatedly back and forth, like the LFO, just turns the knob to four different settings at different times, once a key is pressed on the keyboard.

Another simple metaphor is that the VCO/oscillator is like the bow and string on a violin, whose vibration creates a sound; the body of the violin is a resonant chamber, or basically, a VCF/filter, like the mouth you mention, that gives shape (timbre) to the sound emitted by pulling the bow across the string.

But yes, also: once you realize just one partial with its oscillator/aka waveform, filter and amplifier is equivalent to a complete Juno 60, and realize in the JP-80 that one patch is like having multiple Juno 60s running at once, etc...... pretty soon, you realize why you don't really need any other synth out there, and that all of them are, one way or another, just variations and adjustments on the same two, core things: tone, and modulation. :)
marctronixx
Posts: 187
Joined: 01:39, 16 September 2007
Location: Los Angeles

Re: LFO, VCO, VCA

Post by marctronixx »

really appreciate your posts gents!!

I see all the time cats on videos just moving sliders, etc and yeah ive done that and kind of have bumped into a decent patch or two in my day, but i dont want to bump into it, I want to approach it from a educated way,, hence my asking this question.

id like to got down the rabbit hole a bit--i am a decent study on things I am interested in, but i just need direction to focus that attention on, and I will start with looking up curtis' stuff.

again i cant thank you guys enough here. the jp08s are really helping me to understand the Jupiter better and your directions here are gold.

cheers!
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