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Cool, glad it worked out. Good call about C1--100n is usually more than enough. 470n is a bit overkill, IMO. Maybe they chose that for impedance reasons? Dunno.

You can't jumper C1. It's there to decouple the AC guitar signal from the DC path of the effect. Reducing cap values generally means reducing bass response, not the other way around.

Increase C3 to shift the range of clipped frequencies downward. A 220n or 330n should suffice.

I got an email from Smallbear letting me know they made some changes to their website which may cause some of the links in the project documents to become broken. Unfortunately, I don't have time to deal with this right away. In the meantime, if you are unsure about a part/component linked up to SB in any of the build docs, please feel free to ask here for help. The issue is not on their end---it's the non-updated links in the docs.

It gets fairly out of control, almost oscilation. It sounds like a constant feed back and keeps going and going until I turn it down to regain control then bring it up. Its an awsome noise rock delay and using a kickdisk type control I have it doing some awsome sped up/slowed down analog tape like stuff. Maybe its just the settings Im using? anything over 12 o clock it gets crazy.

The dwell control will oscillate somewhere around or after the midpoint. That is normal. The "secret" is to use the dwell and echo controls together to find the right balance. Setting the Echo around 25% and the Dwell just before the midpoint should give you almost infinite non-oscillating repeats that are somewhat dark sounding.

As gtr2 mentioned, the longest delay times will have some artifacts/digital noise to it due to the minimal filtering. You should not hear this at medium delay settings, so if you are experiencing that I would double check those resistor values. The gains stages are balanced for very clean output (as much as possible with this design). Using an electrolytic for C14 instead of tantalum should not make a big difference. The tantalum is preferable for filtering the 2399 from everything I have read, but I have built many delays based on that chip using only an electrolytic there.

Thanks Brian. Frankly I like the idea of putting the regulator on the RR board and putting a resistor in R19 as that would simplify things and I would still be pushing 15v which I'm going to declare close enough for me at this point 

I will take a step back and go one step at a time as you suggest.

Cool. Hope it did not sound like I was picking on you...

gt2 has pointed out the the Cave Dweller PCB is just a bit wide for a straight plop down into the 1590A. I made a last minute change on the borders which appeared to be within spec (less than 1.4" wide) but as it turns out is just about 1/2 mm wider than it should be making it difficult to lay flat on top to the jacks.

Here's what to do. Place a piece of sandpaper flat on a table. Hold it down with one hand and then swipe the left side of the PCB back and forth about 10-15 strokes. Then repeat with the right side. It only takes about 10 seconds to do and it removes just enough to get the PCB straight down. Do not over-sand! 10 -15 strokes on each side is all that is needed! REMEMBER: PCBs are made up of a fiberglass backing. The dust is not something you want to breathe directly or keep in your work area. Make sure you use proper precaution when sanding (well ventilated area or using a mask), and dispose of the PCB shavings immediately.

If you don't have sandpaper, use an Xacto knife and trim the sides instead...the material can be trimmed fairly easy. This also creates a little mess to clean up, but it does not produce dust.

Starting today, I will be doing this procedure myself on the Cave Dweller PCBs before shipping them out to save customers the trouble.

The green highlighted area in the image below is about the amount that should be removed.

Ahh, okay I see what you are getting at now (I had forgotten about that discussion). Yes, you could run the circuit at 18v and then Vdd at 15v only (remembering that the MN3005 has a max Vdd supply of +/-15v). I don't think that is going to offer any real advantage, though, esp. considering you are not going to get 18v exactly off a charge pump. It will probably be closer to 17.5 or so. Which ever way you decide to go, do use the correct type of regulator and try wiring it the way I mention here: www.madbeanpedals.com/forum/index.php?topic=3756.msg36736#msg36736

Get the power thing sorted out first, and try to get your BBDs passing delay. Then we can tackle the modulation

I've built one with the B variety. It sounds good but not terribly gainey. The C is the better choice and is what the stock unity uses. Most of the hFe for the G2 measure around the 550 range, IIRC.

You are going about this the wrong way. You need to install an LM7815 on the Road rage board (the T0-220 type) to get a regulated 15v supply to the PCB. R19 can be anything between 22R and 100R---the values doesn't matter too much. You do not want to supply 18v to the Aquaboy and try to regulate it on that PCB. A 78L15 is not going to supply sufficient current to power the Aquaboy with two MN3005.

You need to break something like this down into manageable steps first instead of hooking everything together and hoping for the best. Install the regulator, confirm it puts out 15v. Remove the double delay board and MN3005. Hook the power supply up to the AB board. Measure the supply pins on the ICs and the socket for the MN3005 to confirm you are getting power to them. At this stage, I would only hook up one MN3005 on the AB PCB and confirm that delay is passing, but I guess that depends on whether or not you have the clock and bias trims on there. If delay is passing then hook up the double delay board and bias. Hook up modulation last and test.

This kind of thing is too complicated to just wire everything up without doing proper testing of supply and voltages first. When you break it down like this, you give yourself a much better opportunity to debug as you go along.

What about on the other side of R6, the 1k8. Are you reading about 9v there? R6 may be the problem.

Just to be sure: you have the transistor turned 180 deg. from the drawing on the silk screen? It appears to have the opposite pinout.

Thanks for the heads up. I just checked and yeah, it looks like there is a 1mm of extra border than there should be. I played around with it a bit and found angling it a hair is enough to get it in. Sanding the sides may not be necessary if the jacks are placed close enough to the top of the enclosure...or at least I hope not.

Hey Brian, you might try changing D4 and D5 to Schottky 1N5817, or change your regulator to a 7812. I'm not sure how well a 7815 will maintain regulation with only a 1.8 volt greater input voltage. Dropout voltage is usually about 2 volts.

Excellent point. I thought about the schottkys but not the 12v. I will try those out and report back ASAP.

Cool idea!

It was actually Jacob's