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Re: Animation LFO (was: Mock up the MOTM-390 uLFO)

2001-12-05 by mmarsh100

OK, Jurgen wins.

--- In motm@y..., jhaible@t... wrote:
> IMO, the uLFO should not be a scaled down version
> of the big one, but something to complement it.
> 
> So here's a completely different idea:
> 
> What about an "Animation LFO" ?
> To breathe life into static patches, you need a lot of
> subtle modulation rather than the most exciting of
> waveshapes.
> 
> In the JH-3, I have a module that consists of five 
> triangle-only LFOs (independend frequency control).
> And it has an extra output where all LFOs are
> added which are not used on their individual outputs.
> 
> The idea behind this was to have either
> (1) a bank of simple, independent LFOs to modulate
> various destinations sat different rates, or
> (2) to have a "pseudo random" waveform from adding
> several LFO outputs. This is very useful as a 
> non-periodic modulation source that doesn't 
> make unexpected "jumps" like filtered random signals.
> (3) A mix of both.
> 
> Translated to MOTM, this could be:
> 
> 4 triangle LFOs in one module.
> 4 Pots for Frequency of each LFO
> 4 Output jacks with a clever assignment:
> 
> Outputs 1 ... 3 carry LFO outputs 1 ...3.
> Output 4 carries the weighted sum of all otherwise
> unused LFOs, including LFO 4.
> 
> This means:
> 
> If all jacks are used, you have 4 independent LFOs.
> 
> If you only plug in output 4, you have 
> (LFO1+LFO2+LFO3+LFO4)/4 at output 4. (This is is much better
> fluctuating voltage source than Buchla's infamous
> Source Of Uncertainty, IMHO)
> 
> If you plug in output 1 and 4, you have LFO 1 at output 1
> (of course), and still (LFO2+LFO3+LFO4)/3 at output 4.
> 
> If you plug in output 2, 3 and 4, you have 
> LFO2 at output 2, LFO3 at output 3, and
> (LFO1+LFO4)/2 at output 4
> 
> Complicated? No. Each unused output is simply propagated
> to Output 4, and the volatge swing there is constant at +/-5V.
> 
> If you have tried this once, you never want to miss it again.
> You can even do some crude "Fourier Shaping" of the waveform
> at output 4 when you set integer ratios for the LFO Rates.
> (Integer ratios will only be approximated -> animated
> waveforms ... No integer ratios: Pseudo random ...)
> 
> JH.

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