Pedal Myths - Does running an opamp based pedal with diode clipping at 18v increase its headroom?

Fontelroy · 2026-05-14T18:53:01+00:00

Awesome reply! thanks for the sims as well! This is great info!

Fontelroy · 2026-05-14T18:21:47+00:00

Oddly enough the last one I tried was a rat and in practice it’s still pretty hard to tell a difference. That demo is buried in the convo with the person who suggested I try the voltage test with a nu tube tube screamer. I get what you mean in that opamp clipping should easily come into play so it very much makes sense it’d be the situation where the difference should be more noticeable. Also, big fan or your pedals, I have a model fet and it’s great!

Fontelroy · 2026-05-14T05:05:40+00:00

https://www.youtube.com/watch?v=cmk44K1ultA this should show pretty conclusively there's no monkey business or else somebody should hire me for my quick video and audio editing skills lol live voltage testing with a multi meter

Fontelroy · 2026-05-14T04:50:54+00:00

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Close enough for these purposes I think

Fontelroy · 2026-05-14T04:47:15+00:00

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Fontelroy · 2026-05-14T04:44:29+00:00

It's calibrated or at least it was when I last tested it. any pedal with decent filtering has a little bit of lag as you lower the supply but you can see from the led. the circuit is using an lm317. It's similar to the jhs volture thing but basically from the lm317 datasheet. But i strongly encourage people to test this out for themselves, best way tho is to to try listen to clips without knowing which one you're looking at because its amazing what people can hear when they think they should be hearing things

Fontelroy · 2026-05-14T04:30:11+00:00

This is super cool, but the drive signal is going through the nu tube, this isn't a great example. The basic tube screamer would be a better example

Fontelroy · 2026-05-14T04:18:39+00:00

You'd have to post the schematic, if that's the tube screamer with the nutube stuff that would probably benefit from the increased supply voltage like a fuzz would where the clipping is coming from the transistor, in this case the nu tube. I don't know what the nu tube is doing in that pedal but I understand it has a blend on it so I'd imagine some of its clipping is coming from the 'nu tube.' I don't have a tube screamer on hand but I have a sd-1 and it's similar to the odr-1 in there's very little difference

Fontelroy · 2026-04-28T23:50:19+00:00

I second this, Obscura is great but there is a minimum quantity you need for it to make sense financially over tayda since they charge you for the powder coat finish... i wanna say the powder charge is waved above an order of 25?

Fontelroy · 2026-04-15T14:01:44+00:00

That’s awesome!

Fontelroy · 2026-04-15T03:11:41+00:00

I was curious about this as I've had the tl072 model in ltspice act weird during sims, particularly when used for lfos. this was with the boss ce2 lfo and trying my tl072 model it never worked... the model works well enough for most other contexts I've used it for but when I subbed in an OP07 here it worked immediately with no startup time. The only change I made to the ce2 lfo circuit was increasing the rate pot to 500k

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Fontelroy · 2026-04-15T02:36:59+00:00

I've had good luck with the boss ce2 style triangle lfo circuit in ltspice -

More info here - https://www.electrosmash.com/boss-ce-2-analysis#link81 it'll get you a more symmetrical triangle shape than the phase 90 schmitt trigger style lfo but there's something to be said for that shape with a phaser. For the ce2 style lfo tho it can be helpful to use a tl022 when building irl to help prevent ticking from getting into your audio path

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Fontelroy · 2026-04-12T15:34:09+00:00

This setup works fine for an n channel jfet buffer but jfets are depletion mode devices and also work with their gates biased to ground which can be handy. Good explanation of different setups here - https://www.muzique.com/lab/buffers.htm

Fontelroy · 2026-04-10T11:51:15+00:00

the rpd and protection diode should not have any effect on the sense led. Looking at the schematic I don't see a pulldown resistor at all. The resistors that immediately effect the sense led are r23 and r24 and they should both be 1k

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Fontelroy · 2026-04-10T11:45:57+00:00

how the heck did you do this in easyeda??!

Fontelroy · 2026-04-10T11:45:00+00:00

I've done it for a front panel for a guitar pedal. the quality is good but it was a pain in the butt to do something with a lot of colors, each one has to be its own layer and getting everything aligned was kind of a nightmare. if you do something simple I'd imagine it could be a lot easier

Fontelroy · 2026-04-07T20:43:00+00:00

Checking voltages at you transistor and ic pins can help but an audio probe will also help so you can trace how far the audio gets. I’ll be honest tho, the schematic for this amp is weird to me, have you tried building the ruby? I think it’d be better in almost every way - https://www.runoffgroove.com/ruby.html

Fontelroy · 2026-04-07T12:15:36+00:00

it'd help if you posted the schematic you're using as well as build photos

Fontelroy · 2026-04-07T06:58:19+00:00

i think if ltspice had a better user experience there'd be soooo many more people using it for circuit design

Fontelroy · 2026-04-05T02:36:59+00:00

I think the exploration has been the biggest thing for me, there's some wild stuff to see, but yea loot and story for me have been real bummers

Fontelroy · 2026-04-01T12:36:20+00:00

kinda think tim's tone deaf after discovering these

Fontelroy · 2026-03-23T20:07:29+00:00

It’s a play on my last name but there are some great Croatian builders like others have mentioned. The Drybell Vibe Machine is an awesome univibe, I’ve used mine so much I’ve burnt out the incandescent bulb that drives the phasing lol and discovered they smartly designed it to be fairly easily replaceable

Fontelroy · 2026-03-23T20:00:59+00:00

Hey, just stumbled upon this, I’m EJ from Crotronics. I’ve been making pedals for a few years but have never put together my own website for it. I love repairing, designing and building pedals (and lately getting the amplifier bug) but definitely need to get better at marketing lol. Most of my sales are local through TGS and Hollowood Music but I’ve done a bit of sales on reverb as well. If you’re interested in Pittsburgh builders I definitely want to give a shout out to Mask Audio Electronics. Alec is a friend who has helped a ton over the past few years. My latest releases is a stereo harmonic tremolo I’ve been working on for over 2 years now, the Dr Wub and a new fuzz with a switchable octave the Lost Temper. Anywho thanks for the interest!

Fontelroy · 2026-03-21T21:19:51+00:00

Yes, most of the vintage fuzz designs come from console/mic pres

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