Rub a Dub reverb

[night-B]

I was thinking about these mods (please note they are uneverified yet) :
-Switching between two bricks with a 3PDT:
Make a sandwich of two bricks , Attach pin 1 of brick 1 to pin 1 of brick 2, repeat the process for pin 2 and pin 4, each pin going to it's corresponding pad on the Pcb.
Wire a 5k resistor on each pin 5 and 6 of the two bricks, tie each 5k of 5 and 6 together, and run this on a 3pdt, at two opposite poles, center pole is wired on the left side of R9 to the PCB (so you can omit R9 and R10 on the PCB now). Wire pin 3 of each brick at opposite poles of the 3pdt, and center lug to pad 3 of the PCB. You can now swich between two bricks with your feet  (you can use a DPDT if you prefer using a toggle switch.
- Feedback mode: omit R9 on the PCB, on the right pad of R9 solder a wire going to pin 1 of a SPST (momentary footswitch, or toggle switch to your taste), pin 2 of the SPST run a wire soldered to pin3 of the brick.
Feel free to comment if you think I'm wrong and they can't work.

[alanp]

Interesting idea... with the bulk of a brick compared to a PCB, I'm not sure that it wouldn't be just as worthwhile to just layer two complete boards in a deeper enclosure, or to have them side by side like how Juan did his. Plus then you can chain them together, where your idea means that you can't have both at once.

[night-B]

I was thinking about that as I don't want both on at the same time and to avoid having 2 input and output filters etc, getting fewer components and shorter signal path, with the possibility to switch between long and short bricks.
Thinking about the feedback mod, signal shouldn't be boosted, so avoid changing the resistor mentionned in the pdf doc. Will try that as soon as I get my bricks home...

[gtr2]

The feedback mod won't work without some sort of buffer in between.

With the brick "stacking" you'll need to use a 7805 because a 78L05 won't handle enough mA to power both bricks simultaneously.  But I'm still not sure it would work without running into some other issues.  Feel free to let us in on your results 

Josh

[night-B]

You are right, forgot that belton need a fair amount of supply, so I need to reverse the regulator because 78l05 and 7805 have different pinout...

[p_wats]

I've built 2 of these in one enclosure and, to be honest, I don't find the difference between the 2 bricks (short and long) to be that astounding. I'm thinking of just wiring 1 board with 2 mix knobs to toggle between (giving 2 settings to quickly stomp between).

That said, having them both on at full mix is pretty fun...

Are there any other mods for this circuit (it's great as is! I'm just curious)?

[juansolo]

That said, having them both on at full mix is pretty fun...

It's why I did it

The next ones I build will probably be short brick stand alone ones. The difference between the long and short isn't massive, one sounds slightly bigger, the other slightly tighter. But the pair in one box allows me to have one set for a subtle reverb and the other for a full on ambient thing.

I can't see any reason why you'd want both in a box where you could only have one on at once, the difference just isn't big enough really to warrant it.

[GrindCustoms]

I really like the medium brick that i used in my built.

They're 2 easy mods to perform on this circuit, replacing R17 with a 25K pot to have a level adjustement, get some nice boosting out of it, or with more extreme setting it helps to keep the sound in your face instead of sitting behind.

And there's C4 that can be replaced by a pot and caps so you have a Tone control.

Hope....i've pointed the good components number.....

[njkke]

can you explain better the C4 mod?  Thank you

[GrindCustoms]

can you explain better the C4 mod?  Thank you

Sorry, C4 stays in place..........The way to add a tone knob, is to replace one of the two 10K resistor at the output(R12/R13) by a B10k pot with a +/- 33nf np cap going to ground.

So lets say R12 input eyelet goes to lug3 of pot, lug 2 --»33nf--»ground and lug1 goes to R12 output outlet.

Thanks to CJ for this mod!

Rej

[bigmufffuzzwizz]

They're 2 easy mods to perform on this circuit, replacing R17 with a 25K pot to have a level adjustement

There's only 13 resistors in this project..not sure what you mean by R17? I assumed to add a boost(level control) knob you'd play with the R5 that Josh mentions in the BOM..Increase from 15k to 18k. I'd think if you put a 25K pot there..maybe I'm wrong.
Also kinda confused why you'd put a tone control in the power supply section, not part of the audio signal (R12 and R13). If that's correct I'm very curious why that would work?

[Knut Koupee]

They're 2 easy mods to perform on this circuit, replacing R17 with a 25K pot to have a level adjustement

There's only 13 resistors in this project..not sure what you mean by R17? I assumed to add a boost(level control) knob you'd play with the R5 that Josh mentions in the BOM..Increase from 15k to 18k. I'd think if you put a 25K pot there..maybe I'm wrong.
Also kinda confused why you'd put a tone control in the power supply section, not part of the audio signal (R12 and R13). If that's correct I'm very curious why that would work?

When replacing a resistor with a 3 lug pot what do you connect where? Pin 2 & 3? Does order matter?

[Parra]

I think he wanted to say R9 and R10, you can substitute one of these resistors for a 5kB pot.
lug 1 and lug 3 goes where the resistor was and lug 2 with a 68nF goes to ground. This should work as CJ damp control, just the values are diferent. (10k for 5k and 33nF for 68nF)

[gtr2]

When replacing a resistor with a 3 lug pot what do you connect where? Pin 2 & 3? Does order matter?

It depends on what the application is but to use in in place of R5 on the rub-a-dub you'd connect to the R5 pads to pins 1 and 2 on a potentiometer.

I'd recommend putting a 10k in series with a 10k pot.

[Knut Koupee]

When replacing a resistor with a 3 lug pot what do you connect where? Pin 2 & 3? Does order matter?

It depends on what the application is but to use in in place of R5 on the rub-a-dub you'd connect to the R5 pads to pins 1 and 2 on a potentiometer.

I'd recommend putting a 10k in series with a 10k pot.

Thanks for the info!

Does it matter which connector pads for R5 on the board goes to pin 1 or 2? Likewise for the resistor - can it connect to either pin or should it go to a specific one?