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That's a really clean spray paint job! I have never been able to get top mounted jacks to work in a 1590b. Thanks your work on the blog, I use it a lot. Do you know what the jfet is doing to the circuit?

Thanks for all the kind words. I would gladly share this project. I need to work on getting it into a human readable form.

Just finished off and handed off a build to a friend.  He wanted a pedal that sounded like Dinosaur Jr, specifically the tone from the song Kracked.  Kinda a tough order but sounded like a fun challenge.  So I did some research and yeah as expected J Mascis is a muff guy.  From what I read he had some V1 Triangle Muff that he loved (later it was stolen) during the recording of that album.  No additional info.  Also read he has a custom muff that he added a switch to bypass the volume for solos.  I kind of felt that would way too loud, so instead I opted to add a boost at the end.  But I thought it would be kind of fun to add a modified Electra Distortion instead of a clean boost. 

I spent a lot of time bread boarding the pedal and then comparing it to the recording to trying to dial it in.  I felt like the recording had a bit more note clarity than your standard muff, so I started with a V1 schematic I grabbed off Kit Rae's site.  Then tweaked some of the caps to let a bit more highs through, I also used the Pharaoh tone stack.  Honestly I think now that I could have used a fixed resistor, but what's one more knob.  I am pretty proud to say I think I nailed it.

The Electra distortion at the end adds a whole bunch of versatility.  Gives you a nice overdrive and then you could crank on the fuzz to really smash it.  Or vise versa.  Watching the dude play it for the first time was the most fun.  I was even more surprised at the note clarity we got out of it.  Pretty happy with the results.  I hope he is too.

He asked to call it JC Mascis cause his initials are JC... I would have rather called it Dino Jr, but hey, its not my pedal.  I'll have to make another for myself. 

My girlfriend did the dinosaurs for the etch.  I think they rock, I guess not really dark like the Dinosaur Jr art, but hey...

This was also the first layout I designed in Eagle Cad and thanks to Jacob's JMK Eagle tutorial it was easy.  Thank you for that!  Yeah it could probably be more compact.  I totally had trouble with the Electra, it just wasn't working, but worked on my vero prototype.  Turned out instead of 2.2M I used 2.2K, and of course it was the last component I checked... sheese.  But got it working with minimal damage.  Never assume a part is correct if its not working.  Never!

Love this site and all the resources on it.  Here are some picture on my dirty project table. 


 

I've been using these and so far the quality seems pretty good. Price is great! And no tab to break off, which I like.

I've seen this with some really high gain circuits.  I think jiggling things and touching things might send some signal through it and you see the LEDs light up.  I built one once where the LED were glowing super bight until I hooked everything up (ground was the key) and then it worked great.  Are you having problems with the circuit or just expressing concern?

Cool thanks Willybomb for the tips. 

I just messed with this circuit a bit and I switch the drive pot to A250K, which seemed to give it a bit more gain but not much, I'll probably try to go higher here.  I also changed R8 which in the BOM is 47R, with the cap following it being 2.2uf.  I plugged that into the AMZ F-C filter calculator, and I that makes a corner frequency of 1540Hz.  So I swapped that out for a 180R resistor, which moves it down to 402Hz.  Now, I'm not well versed in what frequencies translate to what tones I hear aside from lower is more bass, but this totally changed the dynamic of the circuit.  Suddenly the treble was not overkill like before but instead the whole tone of the distortion became more punchy and fun in my opinion.  This might be too low, maybe too much punch, so I might swap it out for something lower like 100 or 120, but wow, it seems that the mix is more balanced. 

Yeah, I was only thinking audio probe to see if the oscillation was happening right away or actually coming from the transistors. Something is funky and I hope you figure it out.  Your in good hands though with Midwayfair. More pictures would help. Good luck!

Just thinking through your last post, with the change to the oscillation tone by swapping a cap. Do you have an audio probe? Check the circuit to see where the oscillation starts.

Too soon to tell. So far it's just been wanking on my testing rig. It's definitely worth boxing and giving it real go in my band. I'm big into tap tempo based delays, but they can get a little much in solos, so I'm hoping this fits the bill as a straightforward clean delay. I'll post an update when I get a chance to really try it. But so far so good!

Are you grounding your jacks?

And it was the diodes.  My bad, delay works great now. 

Could it be a grounding problem? Or some solder that is connecting something that shouldn't? Do you have some pictures? Maybe you can turn this into a cool "feature"

Doh!  I've been looking at the schematic while eating breakfast before work, thinking what could I have done wrong?  And there it is, possibly, right before my eyes...

I switched diodes 1 and 4.  I'll have to swap them out later tonight to see if that is actually the problem.  Its right in the area where you pointed out Madbean where there might be a problem.  Thanks for that tip which helped me catch my error.  I'll post an update when I get a chance to do the swap.

Thanks for the help!

Its pretty crowded on this board, so I took 2 angles.  You can't see R27, but I measured it and it is 618R, should be good.  R26, R28, and R29 measured ok...  shoot...

I've verified the Boneyard.  Didn't take any pictures of the PCB, but it does work.  It's just a bit too bright for my tastes.  Wondering if increasing the value of the last cap in the chain would fix that.  Or changing out one or both of the LEDs in the clipping section.  I tried a few ICs and not that much of a difference.  Also surprised its not as gainy as I expected.  Or maybe its just not my bag?  Anyone else experience something similar?  Any mods you suggest?