A pedal that lights on fire when you play

[facelessfx]

One of my latest custom orders is a Muff style effect. The guy wanted an etched chimney graphic, where the chimney has a couple of bricks missing. He wants the "fire" to glow through the missing bricks when he plays. Not always on, but to light up depending on when and how hard he plays.

I'll cut the bricks out after etching the chimney. Then I'll fix red, orange and yellow behind the holes.

As it's a BMP style effect, I first thought that I would try using red LEDs as one of the pair of clipping diodes, which would shine through the holes. Would be an elegant solution.

However, while this can produce a nice sounding distortion (see EQD Hoof), the LEDs don't have enough current through them to light up very brightly.

Onto Plan B.

I stipboarded a very simple circuit that splits and buffers the input, sending the signal to the Muff and also through a side chain that boosts and rectifies the guitar signal (an envelope follower) and then feeds LEDs. This works perfectly! The LEDs don't just turn quickly on and off; they vary in brightness depending on how hard you play. They flicker just like fire!

I found a bonus too. The rectifier circuit requires a couple of diodes. These can be LEDs! So the circuit want just drive the LEDs, it actually contains two within itself, that have the same flickering effect. So I think I'm going to use 4 LEDs in total to produce the fire effect.

I hope it looks as cool as I think it will.

Pics and maybe vid to follow when I've built it

[facelessfx]

I decided against the above way of lighting. It got unnecessarily complicated. It wasn't lighting the LEDs very brightly because, while the envelope follower was good at voltage following the input, there was only enough current to dimly light them. The word Transconductance went though my head. Then I realised that when thinks start to get too "clever" it usually means I'm doing something the hard way.

So, the better solution was to have the LEDs powered from the rail, but have the envelope follower switch them on and off.

One quad op amp. Two to buffer each split path, one as a precision rectifier, and one as a comparator. When the rectified voltage goes higher than wherever I set the trimmer, the LEDs get the full 9V (actually about 5V I think) and all the current they need to glow brightly.

There's a second trimmer to set the sensitivity of the trigger.

https://instagram.com/p/2lVRmHM3a-/

https://instagram.com/p/2lUOfeM3Y-/

I'm pretty happy with that. And the little stripboard firemaker can be fitted to any pedal (as long as you're happy for the input to be buffered).

[facelessfx]

Oh and the pedal sounds pretty good too

[facelessfx]

Guts:

image.jpg (156.18 KiB) Viewed 5524 times

https://instagram.com/p/2lUTM5s3ZI/

[goroth]

That is super rad!

[Chankgeez]

Yeah, that popped up in my YouTube feed a few days ago.

[Jwar]

Love it dude!! Super cool! Also your PCB look is fucking amazing!

[facelessfx]

Love it dude!! Super cool! Also your PCB look is fucking amazing!

That's a Wilson Effects "Dirty Beaver" board. I designed it and kept a few for cheeky BMP builds.

[facelessfx]

Just got the customer's review and a clip:

The pedal arrived on Saturday and my main pedal friend just happened to be coming through town that day so he came by and we plugged it in for the first time.

The pedal is very very beautiful from an aesthetic standpoint. I love the work and the choices you made for knobs and how clean the etching it. It's crazy sexy. My friend is familiar with many different muffs and he thinks this is an exceptional take on it. We're not much on BSing each other with this stuff and we're very candid when something doesn't rub us the right way......I was unsure of the muff design and that unsureness was intensified recently when I listened to the Greer Tar Pit. It was cool, just not my thing.

The Chimney Sweep IS my thing! Plenty of heavy sounds but also woman type tone. A bit of splatter and bite when you want it but also that searing, compressed, sustaining sound that's just too much fun to play and sounds so good. I've included an impromptu jam from my band's last rehearsal. I wanted to hear the Chimney Sweep with the band playing.....I/we don't play this kind of stuff at all so you'll have to forgive the playing in the clip.....it just made us all want to rock!! Haha...

The pedal works great with my main amps and guitars and that includes p90s, wide range hum buckers and Telecaster pickups as well as Filtertrons in a Cabronita style hollow Tele in the clip. The light effect is fun and really adds a great original vibe to the pedal. My band thought it was killer and so did my friend. I know it will be a hit wherever it goes.

Thank you, thank you, thank you! I love this pedal so much and it rocks so hard....it's been a great experience having you build another very personal and custom pedal for me. I love you work and your ear.

The Chimney Sweep Fuzz is more than I'd hoped for.....you nailed it!

Clip: https://www.dropbox.com/s/kneavvt0vojhr ... k.mp3?dl=0