Hello has anyone got a DIY Envelope Follower kit they’d recommend for modulating video? Sensory Translator is obviously the ideal non-DIY equivalent but I’m on a tight budget at the moment.
Thanks!
You can make a simple passive circuit with a diode, resistor, and capacitor. I have one around here somewhere, I should look up the values.
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I use a Doepfer Envelope follower, which is pretty cheap.
And for DIY: I did a project with the 5x Harry Bissel design by Miscreant env. follower in one panel and then I use a 10 band Equalizer (Serge Resonant EQ mk2) to isolate the frequncy inputs, to emulate the sensory translator
Thonk has some Envelope follower stuff / modules that can be used as such function:
https://www.thonk.co.uk/shop/befaco-i²-instrument-interface-full-diy-kit/
more DIY options / schematics:
this is the Miscreant post: Harry Bissell's Fast Response Low Ripple Envelope Follower - MUFF WIGGLER
www.haraldswerk.de Next Generation Formant Envelope Follower www.haraldswerk.de Next Generation Formant
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I have the Vidiot but have also use the Make Noise Maths which can act as an envelope follower. I believe Befaco’s DIY Rampage module is almost a clone and can do the same.
There must be cheaper options out there for a dedicated follower but I would vouch for a complex function module’s many applications in video synthesis. For example, the ability to adjust the slew rate for the up and down ramps individually can really help smooth out and shape the animation of abrupt percussion voices.
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also depends what you are wanting to follow?
if it’s external to modular then the doepfer input module is also an envelope follower (probably what ReverseLandfill uses)
I use a sensory translator, but I also use a lot of the same modulation from my audio modular, mixed in with video signals and often send video signals through doepfer waveshapers/folders and just modulate those with regular eurorack modulation (no scaling needed)
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Hi thanks so much for the replies!
I’m mostly looking to follow audio sources, like guitar, synths etc. I’m looking for a single channel envelope follower in 3 or 4hp to keep with the cadet / castle aesthetic I’ve got going on but doesn’t seem like what I have in my head exists! I’ll breadboard a precision rectifier + low pass combo and some simple filters this weekend and see how far I get.
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Must be nice having tunable freq per channel, I’ve always wanted to build out a grander follower than ST… Mostly for that reason.
Is there such thing as a high pass / low pass situation where you could tune both the upper & lower limit (think range) of what would trigger a channel? I guess I’m not really familiar - must it be specific freq ie 220hz or can a follower be setup as a tunable range ie trigger @ between 200hz to 240hz. Seems dreamy to really tightly dial it in, I find them to be a bit too sloppy for my taste at times
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if you have a EQ with separate band outputs, then you can use those to set the range.
You can mix several bands to get a wider range.
EQ outputs are always a certain width, so you can use that to your advantage.
Most of the time you would not need very specific ranges, just bass-bassmid-mid-midhigh-high-ultra or so, to do audio input movement. like a crossover.
(but the Serge resonant EQ has 10 bands, so that means more fine control)
As alternative, use a parametric EQ for each channel
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A band-pass filter should do the trick.
It lets you set a frequency and width of the cut-off on either end.
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3-band crossover here - pair with one (or three) envelope followers and you’re good to go.
Mutable Instruments Stages with the alternative firmware found here makes for a great utility bank. single stages in “green” mode of the alt firmware act as asymmetric slews which make perfect simple envelope followers. pretty sure slider is rise time and knob is fall time but that might be reversed. you can also use single yellow segments as combination attenuator/symmetrical slews (knob sets slew time, slider sets amplitude).
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there’s a schematic out there for a Buchla envelope follower that’s pretty simple. I built it into 4hp along with a preamp
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Hi,
Just a noob question: how will the generated signal be in sync with the video signal? Can it cause problems similar to unsynced audio VCOs?
Thanks!
Envelope followers are generally used at animation rates, so too slow to need to be in sync with the video signal. In the end I just bought a sensory translator, which for example I might use one output to follow the envelope of a kick on a song and use that to modulate a parameter like key threshold or VCO frequency.
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I think Maths is a good way to go, it’s inexpensive, ubiquitous, and multi-function. Takes up a lot of HP space, though.
Audio rate modulation is definitely an issue with horizontal tearing. I solve that by sending modulation through a sample-hold circuit, locked to pseudo vertical sync. Someday I will do a video demo of this because it’s so important. The building blocks are video synced oscillator, comparator, and sample hold.
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If maths is too big, Make Noise, as well as Joranalog , make individual function generators in 8hp. Nonlinearcircuits has one in 4hp.
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if maths is too big… your case is too small!!!
given all you can do with it in terms of self patching - see the ‘maths illustrated supplement’ for details/some jumping off points
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Make Noise should produce a run of video rate, 0-1v Maths.
Or Maybe LZX should design a video rate, dual function generator. Seems like it could fit within the concept of a Gen3 function block.
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There are so many great audio function generators out there, many with built-in output level controls, which can also be used with a 5:1 scaler (if you can find one).
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Seconded on video rate Maths, would be massively useful