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And just to clarify, it is not needed because it essentially duplicates the function of the resistor in parallel with the delay pot (which is optional anyway).

The resistor is not needed. You can certainly increase delay time by using a larger pot like 100k. How much of it will be useable delay depends on how much noise you can tolerate.

For the Path switch, try cranking up the repeats on the Tape setting and flipping it on and off. This is where it is most noticeable.

Congratulations on the build!

The values prevent heterodyning of the two delay clocks controlled by the current mirror. The different values cause a slight mismatch in delay times but also prevent unwanted frequency noise from creeping in the audio path. The mismatch is not really a big deal since the delay are run in series from what I understand.

Both pdf documents have been updated to reflect the changes.

In my haste to add every mod possible to these delays I added one twice without realizing it!

On the SDX - omit R45 the 1M resistor
On the DD - omit R30 the 1M resistor

This will increase delay times. You can still use the parallel resistors mentioned in the doc if you want to artificially reduce delay time but the two resistors above are superfluous.

Lastly, you can reduce R3 (in both builds) to 470k to reduce the dry volume path.

Reduce R3 to 470k to lower the dry path. That was a last minute change.

I don't know why flipping your transistors caused more delay time...unless maybe they have a different pinout? That's just strange.

Oops! I see an issue. Remove R45 (the 1M). That should increase your delay time even further. I'll update the doc to omit that from the build (same goes for the DD). I doubled down on the Delay parallel resistors without realizing it.

A woody or hollow noise usually indicates a mis-biased transistor. What voltage reading do you get on the drain of the J201?

I would try this: bump up C5 to between 6n8 and 10n, and change the Tone pot to reverse audio (or wire the 500kA backwards).

In retrospect, the tone control on the amp doesn't port all that well to the pedal version. I believe I did suggest changing C5 at one point, but I don't remember if I included that in the build doc.

For the newer sub-mini version I'm working on I've ditched that tone control altogether and picked a simple cut knob which I think serves it better.

Probably the best choice would be the Simply Wonderful Tone Control. You can find info about it on the AMZ site (www.muzique.com). You would sub this tone control in place of R7 - the 10k.

http://www.madbeanpedals.com/forum/index.php?board=41.0

The first of the monthly contests has launched. Please be sure to read the sitckys and ask any questions you have about the rules and stuff in the appropriate threads.

I've also revised the PDF to include the text posted above.

My apologies on the last minute change. Lesson learned - test all builds and multiple volume levels, not just the one you are used to.

[Change R3 to 100k and R4 to 4k7.]

While I was doing by final tweaking before boxing up, I realized that the straight through signal on the delay has too much of a boost to it. The input/output stages of the Micro are different than the other Zero Points (and most PT2399 delays). It's non-inverted, with an input buffer and an output mixer. I did it this way because it saved three parts on the PCB which was critical to fitting everything in.

It's not terribly noticeable at low volumes, but when you start cranking up your amp, there's too much of a jump...probably 5 or 6 db. So, these modified values will bring the input signal much closer to the bypass.

Change R3 to 100k and R4 to 4k7.

Two other notes: an external type DC jack will make this build much easier. I used one and fitting everything in was actually very easy. Remember to use enough length on your wired pots so that you can install them before fitting the PCB into the enclosure.

http://www.smallbearelec.com/servlet/Detail?no=666

Lastly, I set mine up with always on modulation and a Rate pot. I used 68k for R18 and 220k for R19. As I mention in the build doc, these two resistors should be experimented with and you will likely pick different values according to how you set up the modulation (fixed depth and/or rate, variable rate or depth, etc). Those are the values I though worked well when using a Rate pot.

Etched in both cases. For the delay, I used an old plate which I cut up on the band saw and assembled on a little sheet of aluminum.

Here's another....getting close to doing these dang demos.

Probably any of those. I would go for 2n3904 or the 549B. 2n3904 has the opposite pinout.