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Thanks for letting us know it is verified.

Thanks for the note. I have corrected the shopping list and reloaded the zip file.

Terrific! Thanks for letting us know.

Last questions before making a suggestion: does the noise happen regardless of your gain setting on the SK or is it present no matter what? Lastly, does the noise happen if the HBOne is off and just the SK on?

How are you powering the HB One? Is it a charge pump...are you using the same 9v supply as the Sunking?

But having access to the eagle files would allow us to do what ever modifications, layer extractions we wanted without asking Brian all the time.

I understand where you are coming from but this is not something I am willing to do. Releasing the Eagle files isn't just releasing them to the members of this forum, it's releasing them to the entire world. Too much opportunity to abuse.

On the positive side, if you verify all those projects (or at least build them) I've got something extra special to send you to say thanks

As mentioned before, pin11 of IC3 should definitely be 0v. It's connected to the ground plane.

Thanks for the update on verification

[02.22.16]

02.22.16
Narosla
- Based on the Xotic EP Booster
Holy Roller
- Based on the Bajaman LA2A Optical Limiter

Also - the PNP Photoshop file contains just the silk screen side of the boards (as a layer) since this was requested.

Correct. It's actually explained on page 4.

[One way Brian could help is to widen the space between the traces and the plane.]

One way Brian could help is to widen the space between the traces and the plane.

I hear you, but it is unlikely. The isolation pour is 28mils on all the EP stuff and it would be difficult to get it much wider than that without having to make some compromises on PCB size. But, the nice thing about single sided designs is that it very easy to hit a spot with some solder wick if it looks sketchy.

Those pins are for the actual I/O pads on the PCB. On MBP layouts, you will usually see them for input, output, ground and for the LED indicator.

Correct, the main difference here is that the gain of the second stage is, on average, less than 1. This is by design.

Let's assume the gain pot is set to 10k:
When the LDR goes completely dark let's say it has a resistance of ~100k. The gain is then 0.1
When the LDR is fully lit, let's say it has a resistance of ~10k. The gain is then 1

If the LDR only drops to 15k when fully lit though, then the gain will be less than 1 (~0.67).

Edit: a bigger pot will bring the second stage above unity.

Ahh, right. The light resistance doesn't get small enough for it to be a problem. D'oh! Thanks for clearing that up.

It's really not going to matter if you increase the gain in the first stage or the second, if you run out of headroom you will get distortion. Period. In fact, increasing the value of R13 will increase noise by the tiniest, unnoticeable amount.

My thinking for changing the pot instead of a resistor is that because the pot is wired as a variable resistor, the circuit will be 100% IDENTICAL until you increase the resistance above 10k. As the resistance increases, so does the gain.

Either swap should work fine, do whatever is most convenient

Right but the total gain output over both stages is multiplicative. The idea is to get more output without applying too much gain to either stage. For the sake of argument, say the resp. gains of stage 1 is 2 and stage 2 is 10. Your total potential gain is 20. Now increase stage 2 to a gain of 25 and your total output is 50. But, if you made the stage 1 gain say 5 and left stage 2 at 10, you get the same output without applying too much gain to either stage. So, less chance of distortion. If I am wrong, please let me know!

Yup those are just fine.

Changing R13 will give you more volume without much potential of increased distortion so long as you use one of the values I suggested.