Envelope controlled tremolo

[Guybrush]

Hi all

Apologies if this has been asked before but I have a friend asking me about building him a tremolo in which the trmolo speed increases the harder you play. I guess it would be an envelope controlled kind of thing?

Is anyone aware of any DIY projects that offer this?

Thanks in advance

[zombie_rock123]

Theres a fellow over on DIYStomp boxes that seems to be on a mission to envelope everything, might be Kipper? Theres a collaborative thread with schematics, I think its called the Depth Charge but could be wrong.

And I believe the Cardinal is envelope controlled.

[dan.schumaker]

JMK PCB's Blue Warbler is what you are looking for 

[Guybrush]

Thanks guys!

I'll check them out.

Appreciated.

[somnif]

Now I'm trying to think of other goofy uses for an envelope. Like, hooking the LED/LDR set up from the clarinot to a voltage divider that starves a fuzz voltage the harder you play. Good lord there are some strange places you could take this idea...

[juansolo]

Now I'm trying to think of other goofy uses for an envelope. Like, hooking the LED/LDR set up from the clarinot to a voltage divider that starves a fuzz voltage the harder you play. Good lord there are some strange places you could take this idea...

Something we pulled off by accident way back when and were never able to re-create as I can't remember for the life of me what it was and how we screwed it up to get the effect, could be replicated with an envelope. Probably... It's something I keep thinking about doing and just not getting around to. Essentially a envelope voltage sag on a very splatty fuzz in an attempt to replicate the sound of Norman Greenbaum's riff on Spirit in the Sky. If you listen, the harder he plays, the splattier and nastier it gets. I still think it'd be a cool effect with a nasty enough fuzz that responds well to saggage. One day...

[Guybrush]

If you listen, the harder he plays, the splattier and nastier it gets. I still think it'd be a cool effect with a nasty enough fuzz that responds well to saggage. One day...

Anything we can do to encourage you?

I've always fancied an OD that drives the harder you dig in, should be the same kind of idea I guess?

[somnif]

In theory it could be brute forced pretty easy, IE "Clip out the brain dead simple Clari(not) 'envelope' circuit and jam it up the pedals tailpipe"



An LM386, Input to pin 2, 9V at pin 6, Pin 8 to ground with decorations (linking 1 and 8 makes things fuzzy, your choice). 5 is your output, and cap a drain off that to drive an LED (which you can trim/pot to adjust baseline brightness).

Then hook an LDR up to... something. My idea was the bottom half of a voltage divider on a fuzz tranny. Harder you play, brighter the LED, lower the voltage, splattier the fuzz.  The trick with it is to find places where lower resistance = more pronounced effect

(Again, this is caveman engineering, there are better ways to lick an envelope. But its 4:30 am and I've had a double dose of allergy meds, so its the best I've got at the moment)

[zombie_rock123]

I've always fancied an OD that drives the harder you dig in, should be the same kind of idea I guess?

- Sounds like the Expandora to me Although I have always wanted to research the theory to assemble something functionally the same but a different drive sound.

[Guybrush]

I've heard this about the Expandora before but when I've looked at YouTube videos no one seems to mention the envelope 'feature'. Does it definitely drive more the harder you play?

[zombie_rock123]

I believe so - I must admit to having the Fuzzdog pcb half populated for about half a year. Ill have a dig around and see if Ive got the parts to finish to see how good it sounds reactivity wise.

[Guybrush]

That would be enormously appreciated!

[juansolo]

Yep the Expandora does exactly that. Codtone make a board for it.

[somnif]

Yeah, its what the mysterious opto-FET in the circuit is for:
"Rather than having a fixed gain level, the amount of gain is controlled by input amplitude, pick gently and you'll have a clean sound, but the harder you pick the more distorted it gets. Signal comes from after the first gain stage, goes through a diode (D1), and is converted from an AC signal to a DC pulse. This pulse is amplified by IC3B to trigger Q1 to turn on. When this happens current flows though the led portion of IC4, the PC419/H11F3 optofet, generating a variable resistance of up to about 250K parallel to R19 & R20 which are the values setting the gain of IC2. "