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I'm thinking about building a dedicated LFO for use with control voltage inputs on pedals.  In particular, I have a TAPLFO chip that I'd like to box up into a module that I could use with other pedals like flangers, tremolos, phasers, etc.  I'm just wondering what is the "standard", if there is one, for control voltages in synths/etc.  A friend of mine says that it's 0-5V on his Korg synth; the TAPLFO datasheet gives a circuit for a -5V to 5V output.  Anyone else have suggestions?

Here's the outside of the Triangle Mudbunny.  I put a second label on top of the first one to keep the Sharpie from running.  This is my favourite of the three circuits for sure.  The flat/fat/scoop mod is something I saw on Kit Rae's Big Muff site, a mod that's used on one of the boutique Muff copies out there (the Mayonaise maybe?).  Eventually I'll get to a Violet Ram's Head, too.

I built a Mudbunny (also on perf) that had a 4PDT to switch between the Civil War and Green Russian circuits, because I thought that would be easier/more impressive than building two pedals.  It also had switchable clipping diodes, switchable mid scoop, and a power starve control.  Squeezing all of that into a 1590B was an adventure!

Dude, you have to show us this one!

Here's that Mudbunny, along with a gutshot.  This pedal was the first one I ever tried to paint.  Fun fact: red sharpie runs when you put clear coat on it!  Bonus fun fact: Krylon clear coat sticks to carpet and gets all fuzzy!  Painting is the best!

I also put up a gutshot of the Triangle Mudbunny I made at the same time, which is way neater.  For the Russian Mudbunny, I put sockets in for the 4 components that change between circuits (R23, C2, C5, and C8) and ran wires from them to the 4PDT switch.  That switch was a real bear to fit in there, so I had to do away with the terminal blocks and lie down the electrolytic caps.

As for the name, I just feel like "Big Muff Pi" is kind of juvenile and sexist, so I opted for something a little more, uh, inclusive.  As a society, we in the 21st century can do better, you know?

Thanks!

Re: paint wrinkling, one thing that worked for me with the Krylon paint was to clear coat immediately after painting (i.e. within a couple of hours) rather than waiting for it to fully dry.  After the clear coat, I applied the label and clear coated again.  This way the clear coat never got to dissolve nearly-cured paint.  I thought I'd try the on-the-can instructions when I switched to Rustoleum, but no dice.  The toaster oven would undoubtedly help, but my girlfriend will kill me if I buy yet another appliance for my increasingly messy apartment!

If I had this build back, I would try and implement a control voltage input for the LFO, having just learned that that's a thing   There's room for one more jack!

Yeah, good call on the really thin layers.  In retrospect I think a simple test for whether it's cured enough might be to wait until it stops smelling like paint.

Yes it is unbelievably crowded in my enclosures!  That one is a 1590BBS because I needed to lay the board on top of the jacks.  I built a Mudbunny (also on perf) that had a 4PDT to switch between the Civil War and Green Russian circuits, because I thought that would be easier/more impressive than building two pedals.  It also had switchable clipping diodes, switchable mid scoop, and a power starve control.  Squeezing all of that into a 1590B was an adventure!

(My name is Richard, if you're wondering about the label.)

Everyone's builds look so good!  Mine look terrible as I'm still getting the hang of all of the drilling/painting/labelling.  Still, thought I'd share some pictures of my last build: a modded Current Lover on perfboard plus.

I like to build using perfboard because a) I'm trying to learn as much as I can b) it gives me as much flexibility as possible to implement mods.  For the last 6 or 7 builds I've done, I've been using copper tape to make traces on the back.  It's served me well, but I think it might be time to look at etching my own boards soon!

The plan is to eventually build a matching Collosalus to play with TZF, hence the effects loop.  I borrowed the circuit for the stereo output from the BYOC Analog Flanger: I buffered the output of the Current Lover and fed that into an inverting op amp stage for the R output (the L output is tapped from the buffer directly).  I used the other half of that op amp to invert the phase of the signal going into the BBD, so I can switch between additive and subtractive flanging.  The last major mod was a primitive "manual" control, which is just an external pot in series with the clock trimmer.  Turning this up moves the sound from flange-y to chorus-y (and it totally whacks out the sweep, so, you know, not perfect).

Painting remains a real challenge.  I've had the paint wrinkle on me multiple times.  I'm probably putting too thick of a layer of paint on under the clear coat, and not giving it enough time -- the 48h it says on the can is not cutting it!  I'm not hugely enthused by either Krylon or Rustoleum clear coat anyway, as they're both pretty soft, so I might just abandon it altogether in favour of EnviroTex Lite.  The labels are just printable Avery clear labels, and I was too cheap/lazy to buy the full-sheet labels for a prototype build, so I just used a couple of the 2"x4" labels.  Glad I did, too, since the paint wrinkled so much.

I used a 1M pot in series with C3 for the release control.  It diminishes the overall compression, but definitely lengthens the release.  As for the attack, on my build I reduced R6 and put a 1k pot in series with it (this was Jon Patton's idea, and it works pretty well).  Both of these mods are *highly* interactive with the sensitivity control, though.

I'm planning to build a Krankosaurus, but my local electronics shop is out of 9.1v Zener diodes.  Just wanted to check that I can happily substitute 8.2v Zeners into their positions.  Do I ever need to worry about that being a factor when using any typical guitars/pedals?

You're talking about a standard Boss PSA-1-type 2.1mm barrel jack, right?  If so, then yes, the thing to do is to connect the core to the sleeve (or whatever is the "outside" of the barrel) and the shield to the centre.  As you probably know, you need a plug whose body is made of plastic, so that the casing of the plug is not connected to the +9v.

I'd also suggest the Cupcake (Orange Squeezer) as a good candidate for an onboard compressor.  I've built both, and the Orange Squeezer is my favourite -- although actually I tend to use the Afterlife with my Danelectro 12-string.  The OS is really sweet sounding, and probably a slightly simpler build.  The Afterlife has a much slower attack, which gives me a little more of that "Turn Turn Turn" type sound.  I built my Afterlife with a homemade vactrol (LED + LDR + shrink tubing) though so maybe with a proper VTL5C3 it would be faster.

If space is an issue, and you're building it to strictly work with battery power, you can probably omit the power filtering caps too and maybe also the polarity protection diode, although I'd leave them on just to be safe.  I don't know how big the Afterlife circuit board is, but I know Jon Patton has some perfboard layouts that are really small.

I built a Kingslayer II with all 3 mods.  As mgwhit pointed out, differences in the clipping section might well come down to what diodes you used.  I used 1N34As for the normal clipping and 1N4001/yellow LED in the other position, and that's definitely a noticeable change.

The fat switch is pretty apparent on mine.  The thick switch is much more subtle: it's barely noticeable through my little practice amp, but is more so through Amplitube and my M-Audio AV-40s.

Thanks all for your help.  I'll be sure to socket the IC and try the TLC2264 in the future.  I tied the negative leg of C10 to -9v, and I didn't notice any extra noise, so I'm probably just going to leave it, especially since I already laid it out that way in DIYLC and don't feel like changing it

As for the differences in types of capacitors, I don't want to wade into any big debates re: tone, but I will say that I'm going to switch to film caps from ceramics, if only because it's nice to actually have 68nF capacitors that are close to 68nF   All the 68nF ceramics I bought are around 80-96nF.  (And some of my 100nFs are closer to 80nF.)

OK cool.  I'll actually be building it on perfboard (plus), so space isn't an issue.  I might just go with the film cap, but I'm also going to try tying the negative leg of the electro to -9v, which I think is more in the spirit of the original.

Right, but my concern is that the positive lead on the capacitor is not strictly at a higher voltage than the negative.  I don't understand why any polarized capacitor should go here.  In the Sunking it's OK because the bias voltage of the circuit is 4.5v and the waveforms can never go below 0v.  But in the Kingslayer, that's not the case: the DC level of the signal is 0v, and waves travelling through them can have peaks going below 0v.

Re: voltages, in fact the Kingslayer and Sunking gave me my first gotcha moments: I almost started building before I realized my electrolytics were only 16v and I needed >34v for some of the caps in the Sunking