Hey gang
I really like the idea of an envelope based drive pedal (the harder you play, the more gain you get).
I've read that the Bixonic Expandoria does this but I can't find anything on YouTube that demonstrates this aspect of the pedal. Just wondering if anyone here has one and can confirm that they do work like this?
Any suggestions for other drive pedals that might fit the bill would be very much appreciated as well. I'm naturally looking to build my own rather than buy a ready made so extra points if there's a project available. :)
Thanks as always.
The EHX Graphic Fuzz has an "expander" but it effects the output volume rather than the gain. EHX calls it "variable envelope response"
Supposedly the fuzzlord fu2 has a gain expander. It doesn't demo it in the video either
https://fuzzlordeffects.com/fu-2/
"The EXPANDER control changes the amount of internal gain in the pedal. "
On the Superfuzz the Expander is just a standard volume pot style gain control.
Quote from: TFZ on February 14, 2021, 05:09:35 PM
On the Superfuzz the Expander is just a standard volume pot style gain control.
Oh.. bummer
the expandora's dynamics are rather subtle and probably difficult to capture on youtube quality audio. it's a cool effect, but I think the dip switches for the gain structure are the more important feature.
The general concept of "more gain with more attack" would be easy enough to implement, details depend on the circuit you want to apply it to. For example, take a Tubescreamer and any old envelope follower that drives a LDR and an optocoupler. Put the resistive part of the coupler parallel to the 4,7k resistor of the gain stage.
When you hit the strings, the envelope follower will drive the LED of the coupler, the resistance decreases and the gain of that stage increases.
+1. The dynamic aspect of the pedal is subtle at best and it doesn't clean up well so it makes it even less dramatic. It is, however, a unique sound.
Thank you for the replies. I did wonder if maybe the 'envelopness' on the Expandoria may be a bit on the subtle side. Thank you for confirming.
Quote from: TFZ on February 15, 2021, 01:18:42 AM
The general concept of "more gain with more attack" would be easy enough to implement, details depend on the circuit you want to apply it to. For example, take a Tubescreamer and any old envelope follower that drives a LDR and an optocoupler. Put the resistive part of the coupler parallel to the 4,7k resistor of the gain stage.
When you hit the strings, the envelope follower will drive the LED of the coupler, the resistance decreases and the gain of that stage increases.
You make it sound so easy! This sounds like exactly what I want to do but I just don't have that level of know-how. I don't suppose you could link to an envelope follower schem that would work could you?
The Scholz Rockman rack preamp had this in mind so you could go from clean to crazy with the roll of the guitar knob but it never changed the world. I've never played one but it was a cool idea, at least at the time.