Messages

I'm glad I could help you get it dialed in! Are you going to to a build report once it's boxed?

P.S. If you want real chaos, disconnect the Detune control entirely and play hard choppy chords—you'll get wet robot farts!

[The Substitutions]

Thanks for the feedback. It's wonderful to know that other people are making music with something I made!

To make things easier to track, and since the vero and PCB version are basically the same, I'll use part designatioins from the schematic posted here to refer to parts.
 
The Substitutions
The substitutions you made shouldn't change much and definitely won't impact the vibrato. The 20pF capacitor, C6, forms a low-pass filter with R6. This starts rolling off frequencies above 8kHz or so. The 33pF cap will start rolling off at 5kHz or so. This is a gentle filter and is just there to minimize any artifacts in the delayed signal. Depending on your amp and cab, you might not be able to hear the difference in these two values anyway.

The Mix control value isn't super critical either. If the value is too low, you won't be able to get full dry or wet signal at the extremes. If the value is too high, all the action is in the middle of the sweep and you get dead spot at the extremes. 20k should work just as well as 25k.

The Boost
The boost section is somewhere between a ZVEX Super Hard On and an Orman Mosfet Boost. It can get gritty like the ZVEX, but turning the knob doesn't cause the circuit to crackle. You could add a volume control to the end of the circuit by omitting R11 and putting an A100k pot in it's place: connect the original output to lug three, lug one to ground, and lug two becomes the new output.

The other option would be to slap some diodes front to back at the end of the circuit (like a Speaker Cranker). You could omit R11 in this instance too.

The Vibrato
This design is different from others in that the modulation is actually strongest at lower "Lag" settings. Every guitar and guitarist has a slightly different envelope, so the envelope response will be a slightly different. I used a guitar equipped with PAF-style humbuckers for the demo. Lower-output pickups, like most single coils, won't pitch bend as much, for example. 

That said, there are a few parts you can tweak to get more out of it. VR1 (the "Detune" control) and Q2 (the 2N5089) have the biggest effect on how much pitch bend you can get. The gain of the transistor effects how much pitch bend it can produce in the circuit, so a transistor with a higher hfe rating will produce a stronger effect. Sommething like a 2N3904 will work, but will be mild compared to a 2N5089. You might audition different transistors to see if you can find one you like best.

The "Detune" control, VR1, moderates the effect Q2. Larger values will give you more vibrato. I found 5k to get pretty seasick. 10k was capable of full octave drops in some settings. You might find that one of these values is just right for you.

The Enclosure
It'll probably fit into a 1590B, but I haven't measured.

The Typo
Yep—that's a typo; it should be 100uF, not 100nF.

Hey there! I made your original version using the stripboard layout you provided. The circuit sounds really great! Not sure if you're looking for any feedback or not. Let me know and I'd be happy to share some additional thoughts.

I'm glad you like it! I'm definitely open to feedback.

I've got PCBs in hand and they're being shipped out to everyone that has requested one. If anyone else wants one, I have extras. $10 shipped. I'll include a printed build doc. Just DM me!

I'm finalizing the design now. Once I've submitted my gerbers, I'll DM everyone to arrange payment, then I can ship them out as soon as they arrive!

So, here's what I'm thinking.





Basically the same layout as the original, but adapted for a 1590BB. The white lines at the top of the layout picture represent where I would put the jacks. I'll do some final cleanup of the layout and make sure everything is labeled consistently.

I'm thinking a flat $10 per board and printed build doc, including shipping in the continental US. What do you think? Would you want to build this?

1. Yes
2. 1590BB (vertical)
3. I like the 30° look, but I'm a lazy SOB and prefer pcb-mounted pots
4. nope

Pots would be PCB mounted Whether at 30° or 90°. I'll provide a drill template for whatever layout we end up using.

It looks like Dawson hasn't been active for a couple of months and no one has received a PCB from him (hopefully, he is doing well!), so I'm thinking about making PCBs for this circuit myself. I already have a working pedal, so I'd want to make something that other people would want to build. I have a few questions for you all:

• Is anyone still interested in a PCB?
• Would you prefer the original compact 125B layout, or a larger 1590BB layout for more space between the foot switches?
• Should I keep the original 30° knob angle or stick with a more standard ortholinear layout?
• Are there any additional features you wish the circuit had?

Let me know what you think!

While I was very happy with the circuit, I was never happy with the finish on my original vero build. Having decided to learn to design PCBs, this circuit seemed like a good candidate. The thread on the original goes into details about the circuit, but basically it's a short delay with envelop control pitch bending. This makes for unique chorus, doubling, slap back, and vibrato effects.



The enclosure is a Love My Switches limited run. The face plate is a one-sided aluminum PCB from JLCPCB.



The face plate made finishing a breeze and makes it easier to hide mis-drilled holes!



I've been experimenting with ribbon cable and am liking the results. I'm considering making daughter boards for bypass and inputs for future projects to streamline things further.



The circuit is unchanged except for the boost section. The boost has been revoiced to cut frequencies below 140Hz or so. At the lowest setting, there is no frequency cut. The boost gets "brighter" as the gain is increased. This keeps things tight when boosting into an overdrive or dirty amp.

Here's the original demo.

I have extra PCBs and face plates. If anyone is interested in building this, please DM me.

The clipping diode key on the south face is really smart!

I'm working on a multi-band compressor that would use both sides of the LM13700, but I haven't had much luck getting it to work yet. Other than that, I can't think of any circuits that use both sides. 

Can you take a picture of the actual layout? It might be an artifact of the breadboard or something.

Looking good! How do you like the screen printing service?

Welcome aboard!

jwin615 made some great recommendations. There's lots of knowledgeable people here so definitely ask away. We all remember what it's like to be new to the hobby—and there's always more to learn.

I love big knobs.
I love unruly fuzz.
I love this.
Great job and congrats on the first layout working out.
Should've dimed it in the demo though
I've been meaning to build one of these up. Breadboard one a few years back and loved it. This circuit has a bit more going on than the parasit layout. Was that you or inspiration from elsewhere?
Great job!

I wasn't aware of Parasit circuit. I did look at Anderton's comparator fuzz, but this circuit is different from that one as well.