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What color are the bands on the R31 resistor you used? Your voltage there is way, way off.

Shane, you mean a TL074 right? Not a TL072?

I will check into this some more today. I have a few other TLC274 chips on hand. I'll see if I can break it again. At least I'm glad you were able to get it working correctly.

1/2W or 1W will work. This one should be okay: http://www.mouser.com/ProductDetail/Fairchild-Semiconductor/1N5231CTR/?qs=sGAEpiMZZMtQ8nqTKtFS%2fJIts9HBLkA2GFnVtphSpBw%3d

or, http://www.mouser.com/ProductDetail/Fairchild-Semiconductor/1N4733ATR/?qs=sGAEpiMZZMtQ8nqTKtFS%2fD313Kx94AdFtra4VeY%2frMM%3d

Correction #2:

Due to some noise problems caused by the TLC274, use 150R for R28 instead of 10R. This will get rid of the noise when the Gain pot is all the way down.

Aha! Easy solution has been found: increase R28 to 120R or 150R. This drops the supply voltage down a bit, just enough so that it does not cause the noise problem.

At 120R, I measured right around +/-8v on the TLC274. With 150R, it was about +/-7.8v under load. So, either should be fine. You can still use the TLC274 and no noise when the gain is all the way down. I'm putting 150R in the updated doc just to be on the safe side.

-- If anyone needs the resistor, let me know and I will mail you one. I have carbon film.

I think you have measured incorrectly. You must have voltage across R31 in order to have voltage on Q5. Please check this resistor again. Some of the other components will not measure DC voltage because the DC is blocked by a cap, for instance C22.

Let's find out about R31 for sure. The enxt step would be to audio probe the drain of Q5 to see if the transistor is actually putting any signal out whatsoever.

I was wrong on what I thought the cause was. In fact, my prototype had no noise problem with the gain pot as described. After looking a bit further, I found the culprit: I did not test a TLC274 in this build but a TL074. With the TLC274-same result as you guys. So, I can confirm that I am an idiot.

Sorry guys, I should have figured this out sooner. Use a TL074 for now. I'm going to do some part swapping and see if I can get the noise to go away. Somehow, grounding the input of the gain stage is causing the IC to go into oscillation. Previously, I had a 2k stopper resistor between the wiper and ground (on KSv1), but I switched it to be more like the Klon way which is to put it between the outside lug and the wiper. I don't remember if I did it this way because I found the same problem back when I worked out KS1, or not.

The good news is it still sounds great with the TL074. I just thought the TLC274 sounded a little bit better on KS1. I'll see what solution I come up with to make it work again.

I am pretty sure I know what's causing the problem. I'll check in here in a couple of hours with more info.

You can increase the repeat range by lowering R18. Try 1k or 470R.
For the Ring switch, it's easiest to hear it when you have the delay set medium to long, the feedback and mix halfway up or more. Listen to the decay on the delayed notes. When the Ring switch is activated, they should get a little bit dirtier and less defined than when it is off. If not, then perhaps you have the wrong value resistor in R15. Or, you can decrease R15 to increase the intensity of the effect, say 39k.

You should use something there, but you can sub a 1N4001 or even a 1n914 if that is what you have. The voltage drop is lower on the 1N5817.

Any 1uF film with decent tolerance values should work there. I've used MLCC type caps a number of times, as well.

Sure, we can do that.

Okay, I'll check into this further tomorrow, for sure.

Can we get a close up of this area, flat on?

I just put in a pre-order with Sweetwater. $220. Been a long time since I bought a commercial pedal new!