Voodoo Octave Fuzz becomes Compact Direct Drive #2

[Bakersdozen]

After spending at least 4 days idle in the Melbourne processing area, the package tracking is now reading Strathfield NSW. Seems to have shot straight past the ACT along the eastern border for a holiday . . . I'm not going to have a rant about the postal system given current circumstances, but yeah..gaahoouumph

[jugglindan]

Boo!

The parts from PPA arrived today though, so I have the missing caps and pots. The Marshall-style knobs look good too.

I am using the downtime on this build to progress the mini-amp and the TS-808. Need to do the enclosure drilling template and layout.

I should probably think about getting back to my tele build as well. This weekend marks 2.5 weeks since I put the last coat of clear on the neck, and around 6 weeks since I put clear on the body. I should be able to start polishing soon.

[jugglindan]

The package has arrived. It's hard to do justice to the stellar work by BakersDozen on this enclosure with my photos taken in poor lighting, but here 'tis:


Looks amazing, no?

But the attention to detail just gets better with the pinstripes along the side:


I better build the best overdrive ever to be worthy of this enclosure.

I was also struck by the heft of this enclosure. Even with all the internals removed, it feels incredibly solid. Just goes to show that if you like the sound, Joyo make some solid pedals for the price. And if you don't like the sound, then we can rebuild it. We have the technology. We have the capability to make the world's first bionic man, err edit that part out later...

[jugglindan]

The Joyo board:


On inspection, most of the components are surface-mount, making them pretty much useless and near impossible to desolder or reuse. But the pots, switch, and 6.5mm jacks should come off and be usable. The switch will hopefully serve for the harmonics switch, the jacks should be fine too in the new pedal. The pots are all 100k linear taper. That's the right value for the CDD volume, but the wrong taper. And the shaft doesn't match the knobs. So the reclaimed pots won't make it into the new pedal.

A few other components are also salvagable, like the transistors (just cut the leads to avoid heat damage) but that's about it.

The footswitches are just perfect for the new pedal. I didn't desolder, just cut the leads at the circuit board. It is using an unfamiliar PCB with 6 leads out and an integrated LED, so the first step was to trace the board and reverse engineer the pin outs:


It's messy since I didn't know where the connections would run when I started. But I am pretty sure it's correct. One footswitch has 4 leads connected which is perfect for the gain switch, and the other has 6 leads wired up as a standard true bypass. The power LED is on a separate circuit. When on, the input signal goes to the effect board and the output signal goes to the output jack. When bypassed, the input signal is routed directly to the output jack (true bypass) and the effect output goes to ground via a 51 ohm resistor. Note that with this wiring, the effect circuit is fully powered even when bypassed. I don't know what the current draw is in this state compared to when an input signal is applied, but it means that all those pedals on your board are drawing some power even when bypassed.

I don't know if the attached leads will be long enough to reach the new effect board, since the connections are not in one convenient location. Will probably desolder the current leads.

[jugglindan]

A bit more time on this tonight, much of it fruitless. Destroyed the jacks getting them off the PCB, which is fine cause they take up too much space. I will use the same open jacks I always use. Got the switch off in usable form though, so that's something.

I then discovered one issue when using an enclosure drilled for different parts: less than ideal hole diameters.

Footswitches: OK (using the same ones)
6.5mm jacks: holes a little large, but workable.
DC jack: hole is too large for the mini jacks I normally use, but slightly too small for a larger DC jack I have. I am afraid to drill the nicely finished enclosure, so might have to use a washer behind the mini jack to stop it pulling into the hole.
Pots and switch should be OK. Some slack which Joyo could afford since everything was PCB mounted which means the pots don't even need fixing to the enclosure. But I need a strong connection on the case mount to stop things wobbling around. Will just have to tighten the nuts up and use carefully chosen washers.

I also finished the circuit board, adding the final capacitors.

[Bakersdozen]

Yay! Good progress, all good about not being able to salvage parts, it was a nice idea but happy to move on..If you need to, don't worry about drilling that DC Jack hole. Anything can be fixed so go for your life. You can just peel back the stripes if your worried, enlarge the hole and lay em back down. They probably won't even budge with a little enlarging anyway. Sounds like you've got a handle on the rest and woohoo for a completed board. I'm not excited at all, can you tell?

[jugglindan]

I thought the pinstripes had clear over the top. If not then I will peel them back and drill for the larger DC jack. I won't be using it for anything else since I prefer the smaller ones. The larger jack is left over from the Orange Squeezer kit since I used the mini jack on that.

[jugglindan]

OK, I drilled. Of the two holes, I drilled out the larger since the 6.5mm jack was a better fit in the smaller hole. Nothing exploded and no scratches added to enclosure.


Next steps are a mock build to test layout, then off-board wiring, test, and final assembly. The mock build will let me know if I can use the existing footswitch wires or if I need to change them. Changing would have the additional advantage of getting my standard wire colours, which is maybe enough incentive.

[Bakersdozen]

Looking good! I promise I only have a little bit of drool escaping the corner of my mouth. Have you tested your OG build for amp draw by any chance?

[jugglindan]

I haven't measured current draw yet, but I just poked around in the shed and found a cable that will let me rig my multimeter inline with the power lead to the pedal. I will be very surprised if it draws more than 50mA, and slightly surprised at >40mA.