#envelope filter

WMD - super FATMAN

envelope filter

Lovetone Meatball

Mooer Envelope

SRS - VCO DISCO

“ It's simply a fat and juicy envelope filter from the 70s with tons of character and all the funk anyone could possibly handle.  ...  (apparently a copy of the ehx Doctor Q) “

seamoon - funk machine

Envelope Filter Auto Wah - 1973 first version

“ Incredible quack and amazing personality! “

3Leaf Audio Proton MK4 Envelope Filter

DOD Envelope Filter 440

It was probably a mistake to have discovered that the Target website lists a good number of products sold and shipped from Musician's Friend. I had gift card money and saw this thing on sale, and was unable to resist.

This is the Resotron, from Pigtronix. It's a filter effect, mostly — a variety of envelope wah but with a lot of extras. The knobs on the left set the cutoff frequency and resonance; turn the resonance up and it'll self-oscillate, giving you feedback squeals. The switch below that sets the mode, high pass, band pass, or low pass. The other switch is where things get interesting. You can set it to follow the envelope — the volume — of your notes, pushing the cutoff either up or down as you play, or to "pitch" mode, where the frequency follows the pitch you play, making the effect very like a synthesizer's pitch-following filter.

And with the pedal in pitch mode, you can press the "oscillate" button in, and the thing becomes a synthesizer pedal, replacing your input sound with the sine wave of the filter's feedback.

The other knobs are labeled for glide (adjusting the speed at which the pitch will shift), sensitivity (of the envelope or pitch tracking), and blend (which applies compression before the filter). There's a jack for an expression pedal, which changes the cutoff and, in some modes, can turn the thing into a kind of wah-wah; it also will accept control voltage between 0v and 5v, so you can manipulate it from a synth or sequencer.

There's also an input labeled "Trigger", which — if I'm understanding this right, lets you have a second audio input that goes to the envelope follower or pitch tracker while the main signal is going through the filter. This lets you do stuff like ducking — lowering you signal while something else is loud.

Most pedals run on 9v, but this one actually needs 18v; it fortunately comes with a power adapter.

And looking at the box suggests why this thing was over half off:

Some of these bullet points are true and some are definitely not. There's only the one oscillator, and that only sometimes, there's no "SUB" output, and there's definitely no hard sync — and what would that be to? My guess is there was a printing mixup, and this box got the bullet points for the other Pigtronix pedal that's heavily discounted, their Mothership 2 analog synthesizer pedal; probably that pedal's box has the Resotron talking points. (Musician's Friend are the only retailer I've seen the discount at, so presumably they got a big bunch of the misprints to flog off cheap.)

Can I add that it's a gorgeous pedal? The knobs are actually rounded — the sides bow outwards, curved knurls making them easy to grip, and are nicely heavy.