1776 Rub-a-dub deluxe: Who has built one?

[Beedoola]

Options smoptions. All the options you need:

What is it? Like a BYOC with a rotary control instead of a dwell pot?

[juansolo]

Rub-a-dub deluxe, modded a little.

[Beedoola]

details?

[thesameage]

I know that he hardwired the tone with a resistor...

[juansolo]

As mentioned earlier, it's on my site, but to save looking, here's the c&p:

So mine's been modded. The tone has been fixed at the same level as the original and we've replaced the variable pot with a DP6T switch. That way you can choose easily the length of virtual tank you want (finding them on the pot was impossible). Small, Medium and Large correspond to the original bricks that were 2 sec, 2.5 and 2.8 respectively. We've got as close as is indistinguishable there.

Tiny is half a Small (around a second) and Huge is probably around 3.5secs or so. Mahoosive was as far as we believe you can push it without it starting to sound pants. It's proabably around the 4sec mark. Resistor values to replicate this are as follows (they're stacked on the switch):

3k9 Tiny (used a 3k3)
6k8 Short (stacked another 3k3)
9k5 Medium (stacked a 3k)
11k2 Long (stacked a 2k)
15k Huge (stacked a 4k7)
30k Mahoosive (stacked a 15k)

Tone mod:
Omit C9.
R9 & tone pot (between pins 1 & 3) are 5k.

[Beedoola]

As mentioned earlier, it's on my site, but to save looking, here's the c&p:

So mine's been modded. The tone has been fixed at the same level as the original and we've replaced the variable pot with a DP6T switch. That way you can choose easily the length of virtual tank you want (finding them on the pot was impossible). Small, Medium and Large correspond to the original bricks that were 2 sec, 2.5 and 2.8 respectively. We've got as close as is indistinguishable there.

Tiny is half a Small (around a second) and Huge is probably around 3.5secs or so. Mahoosive was as far as we believe you can push it without it starting to sound pants. It's proabably around the 4sec mark. Resistor values to replicate this are as follows (they're stacked on the switch):

3k9 Tiny (used a 3k3)
6k8 Short (stacked another 3k3)
9k5 Medium (stacked a 3k)
11k2 Long (stacked a 2k)
15k Huge (stacked a 4k7)
30k Mahoosive (stacked a 15k)

Tone mod:
Omit C9.
R9 & tone pot (between pins 1 & 3) are 5k.

Did you not find the tone pot useful? Do you have a schematic or layout for how you wired the rotary control?

[juansolo]

I wanted a simple one knob reverb like the original. Tone is useful if you want to darken/brighten the reverb.

Wiring the rotary is fairly simple. Using two poles (they're both wired the same) running from pins one and two on each pot.

Run a wire from pin 2 of the pot pad thorough a 3K3 resistor to the one of the centre pins of the switch.
Run another wire from pin 1 of the pot pad to pin 1 of the same pole on the switch.
So now in pos 1 the signal goes through the 3K3 resistor.

The next resistor (another 3K3) goes between pins 1 and 2 of the switch.
So now in pos 2 of the switch the signal goes through both resistors in series making 6K6

The next resistor (3K) goes between pins 2 & 3 of the switch.
So now in pos 3 of the switch the signal goes through all 3 resistors in series making 9K6

The next resistor (2K) goes between pins 3 & 4 of the switch.
So now in pos 4 of the switch the signal goes through all 4 resistors in series making 11K6

The next resistor (4K7) goes between pins 4 & 5 of the switch.
So now in pos 5 of the switch the signal goes through all 5 resistors in series making 16K3

The last resistor (15K) goes between pins 5 & 6 of the switch.
So now in pos 6 of the switch the signal goes through all 6 resistors in series making 31K3

You need to repeat this for the other gang of the pot on the other pole of the switch. See the photo of the guts of mine for how it should look when done.

[gtr2]

Love that John!

[thesameage]

Love that John!

You should do a board mounted rotary for the radd2!

[Beedoola]

I wanted a simple one knob reverb like the original. Tone is useful if you want to darken/brighten the reverb.

Wiring the rotary is fairly simple. Using two poles (they're both wired the same) running from pins one and two on each pot.

Run a wire from pin 2 of the pot pad thorough a 3K3 resistor to the one of the centre pins of the switch.
Run another wire from pin 1 of the pot pad to pin 1 of the same pole on the switch.
So now in pos 1 the signal goes through the 3K3 resistor.

The next resistor (another 3K3) goes between pins 1 and 2 of the switch.
So now in pos 2 of the switch the signal goes through both resistors in series making 6K6

The next resistor (3K) goes between pins 2 & 3 of the switch.
So now in pos 3 of the switch the signal goes through all 3 resistors in series making 9K6

The next resistor (2K) goes between pins 3 & 4 of the switch.
So now in pos 4 of the switch the signal goes through all 4 resistors in series making 11K6

The next resistor (4K7) goes between pins 4 & 5 of the switch.
So now in pos 5 of the switch the signal goes through all 5 resistors in series making 16K3

The last resistor (15K) goes between pins 5 & 6 of the switch.
So now in pos 6 of the switch the signal goes through all 6 resistors in series making 31K3

You need to repeat this for the other gang of the pot on the other pole of the switch. See the photo of the guts of mine for how it should look when done.

Thanks a lot!

[Beedoola]

I built this to Juansolo's specs. Sounds pretty good. Not very over the top, which I didn't necessarily need, but seeing the "Mahsooive" setting on his graphics, I thought it would be a lot deeper.

I'm pretty certain I built the rotary control correctly.

Also, I notice in the gutshot of Juan's build that C9 still present yet you said to remove it, if not using the tone control. I omitted the Tone Control after trying it and left C9 out...

[juansolo]

Think I popped that off later when I realised.

If you want massive endless verb you'll need to build a reverb with a feedback control. Massive is referring to the virtual tank size. Given a large tank gives a time of around 2.8 sec, the virtual tank on the mahoosive setting would be about twice the size of the head... Feel free to go bigger, no reason why not, I just personally thought it all fell apart if you went bigger and stopped sounding like a reverb. It's DIY dude, experiment, that's what it's all about. There are no right or wrong answers.

[Beedoola]

Think I popped that off later when I realised.

If you want massive endless verb you'll need to build a reverb with a feedback control. Massive is referring to the virtual tank size. Given a large tank gives a time of around 2.8 sec, the virtual tank on the mahoosive setting would be about twice the size of the head... Feel free to go bigger, no reason why not, I just personally thought it all fell apart if you went bigger and stopped sounding like a reverb. It's DIY dude, experiment, that's what it's all about. There are no right or wrong answers.

Thanks. I really like the middle setting. I may add a dual gang pot and a switch to choose between the rotary and the pot. I wasn't sure if the current sounds via the rotary demonstrated as extreme as the circuit could get or if as extreme as it could get given the values of the pot.

Does increase the resistance make the reverb larger/longer?

Thanks again for the info.

[juansolo]

Yep, stick a 50K dual gang pot on there if you want to experience some bigger settings. Personally I thought it sounded best up to around 25-30k (Mahoosive is 30k or there abouts). Go to 100k if you really want to go to town.