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Man, that thing is slick! I've been interested in the GTO for awhile now, might have to give this one a shot! Did you drill out the enclosure yourself or order one of the predrilled ones they offer? Either way that is one hell of a clean build!

Get weird with it and build a PLL 

Holy crap, that's gotta be the coolest Tube Screamer clone I've ever seen! That thing is stunning inside and out, and I love the way you paid homage to the venerable Roland TR-808 with the graphics. Incredible work!

Judge you? For what? That thing is beautiful! Sure, Gibson may not be the greatest company, their guitars can be kind of overpriced, and their fanboys can be rather annoying but that doesn't mean that they don't make good instruments (most of the time, anyway). Enjoy your sweet new score!

You can't go wrong with the classics, that thing looks and sounds great! Nice work!

I'm always super impressed by your builds, that polished enclosure and matching caps and resistors really make for a classy pedal. Great work!

I seen the Sansamp Classic is back on the market.
I never had it, nor built it. Periodically I search some info about it, and every time I see that the schematic is not accurate at 100%, often it had oscillation problem.
I guess the PCB is design by you.
Do you mind to share the schematic you used? Just if you can!
Thanks!

The issue with verifying any of the schematics out there is that the boards on the originals were encased in some sort of ceramic/epoxy combo which made non-destructively tracing them impossible so you kind of had to take it on faith. That doesn't seem to be the case with the reissue from the one gutshot I've seen but I haven't really seen anyone poke around in one yet either. FWIW the schematic I used (which came from GilaCrisis on the DIYStompbox forums) only gave me problems when I tried to build it on perfboard and that was almost certainly a result of the multiple long runs of wire in close proximity to each other going to the DIP switch, which is a recipe for oscillation no matter how you slice it and is the primary reason I ended up making a PCB for it. It seems to sound about right based on the demos I've listened to which lends at least some credibility to the accuracy of the schematic, although to be fair I've never had an original or a reissue on hand to compare it directly.

In any case, here is the schematic I found for it originally:



And here is the schematic for my board with a few minor improvements to the power supply and a conversion to true bypass:

Nice work, I love the graphics! Having just finished up a Fat Pants Jr board I had laying around I can definitely agree that it's a wonderful little boost. It may just be a single JFet but there's definitely something special about it!

Amazing work! That thing looks and sounds incredible, and that layout is something else!

Thanks for the kind words everyone! I've got to admit that even though both of the Sansamp Classic clones I've built so far were for other people I'm still a bit sad to see them go. I really have gotten a bit fond of this circuit and how much versatility it offers. Maybe one day I'll actually build one for myself 

Are you looking to sell any boards on here?

Sure, why not? PM me and we'll work out the details.

Nice work, those look amazing! How do you do your graphics?

I originally cloned the Sansamp Classic for a Nirvana-loving friend of mine a few years ago from a schematic I found over on the DIYStompbox forums, and while it turned out nicely enough it was my first attempt at PCB design and as such left a lot to be desired layout-wise. After I got a few more projects under my belt I decided to try again with a version optimized for top-mounted jacks (I never liked the side-mounted jacks on the originals, especially the DC jack) and otherwise changed up to allow easier wiring, with the idea of possibly making a low-volume run to sell on Reverb since the originals were scarce and expensive at the time. As it so happened, shortly after I finally got around to ordering the revised boards Tech 21 announced that they were reissuing the Sansamp Classic so I ended up shelving the whole idea. That is, until a fellow who had seen my original build contacted me on Reddit asking if I could put one together for him as well. He was in the process of attempting to digitally model the effect and despite having an original on hand wanted another reference copy to verify voltages and waveforms since the board on the originals is encased in some sort of plastic or ceramic. I didn't really have a reason to refuse him since I already had the boards and most of the parts on hand and was kind of looking for a reason to throw one together anyway, so here we are!



The enclosure is a powdercoated 1590BB2 from Tayda. I decided to give their drilling service a try in order to avoid the hassle of hand drilling and was pleasantly surprised by how well it came out. It was quick and easy to use, accurate (except for the LED hole being higher than planned but that was user error) overall and well worth the additional $4.50. As nice as having predrilled holes is though it didn't save me from having to use a Dremel and a file to make the rectangular hole for the DIP-8 switch, which was by far the hardest (or at least most tedious) part of this build.



Another, non-glamour shot view of the front. The graphics are nothing special, just a waterslide decal sealed on with epoxy resin. Getting the hardened resin out of the rectangular hole after the fact was NOT fun and left a rather rough edge.



And of course, the guts. Going for a layout with top-mounted jacks rather than side-mounted like the original and reissue meant ditching the battery, but in this day and age it's pretty much a non-issue. I also had to move the voicing switch on the side down a bit which I admit looks a bit wonkier than the original. Other than that, though, everything fit rather nicely!

And finally, here's a quick demo of me badly playing a bit of "Serve the Servants" by Nirvana:

Nice work, I love your choice of knobs! Those Aion enclosures are slick as hell too. I don't blame you for sitting on it, it's definitely an intimidating project but very rewarding once you get it together!

This is so cool, I like that is kind of like a homage but just a million times better.

Facts. The skull with LED bypass indicators for eyes in particular really does it for me, and it doesn't hurt that it sounds amazing!

I like to think of myself as a fairly competent pedal builder. I've got probably a couple dozen builds under my belt so far, and the vast majority of them have fired right up with no major issues, including several fairly advanced projects. This isn't to say that I've never made a mistake, but up until now it hasn't been anything more major than mixing up the occasional wires or forgetting to mount an IC in its socket. This makes my current predicament even more humbling and frustrating: I finally got around to building and boxing my Snack Shack giveaway board, one of the simplest and lowest parts count projects I've ever done, only to find that the damn thing doesn't work!

Now, I'm no stranger to doing the odd bit of troubleshooting; as I said, I have made the occasional dumb mistake before. I've been looking this thing over for awhile now, however, and I've gotta admit that it's got me stumped. The offboard wiring seems fine: I'm getting power, it passes signal in bypass, the LED lights up, and I can trace signal to the board. However, I'm not getting anything out when the effect is engaged. Using a signal generator and an oscilloscope I can trace the signal up to the input side of C1, after which it becomes significantly attenuated. Signal is present at the base and collector of Q1 and all three pins of Q2 at the same significantly attenuated amplitude, at which point it disappears. Voltages on the two transistors are as follows:
Q1E: 0.000V
Q1B: 0.627V
Q1C: 1.144V

Q2E: 1.144V
Q2C: 1.847V
Q2B: 1.144V

Personally I find it really odd that the Q2 Emitter voltage is identical to the voltage on the Q2 Base/Q1 Collector, which suggests a short somewhere. I can't see any obvious solder bridges or touching leads however, and I've cleaned the board with isopropyl alcohol to remove any excess flux in case that was an issue. I'll probably come back to this later today for a closer look with fresher eyes, but in the meantime if you have any thoughts or suggestions I'd be happy to hear them!

Here are some pictures:







And a close up of the board itself: