Aion Yacana build and mods

[daizee]

So #3 was the Yacana, which is only available as a PCB w/ a parts list and excellent documentation. Leveling up for me...
The Yacana is a hex-inverted based overdrive in the Red Llama/Hot Tubes/Tubesound family. It's a modest circuit in both number of components and controls vs. the Achilles and Vulcan (previous builds). But this required drilling the enclosure too.

I've wanted to try a Red Llama since I had a Fat Sandwich awhile back, but couldn't disable the hard clipping middle section in that pedal. And $150 for a re-issue was more than I wanted to spend when I need NO more drive pedals.

So i built the thing and found it was a bit sensitive in the low end. Thus far I'd only modified clipping diodes and this had none. So... time to learn about filters!

I added a modest point-to-point wired bass-cut (high-pass)  bass filter to keep it from flubbing out early. This worked GREAT, and the pedal is has great low-gain overdrive dynamics now. And the gain toggle pushes it right to distortion/fuzz territory for a VERY usable sound. This thing is COOL.

Stacking gets kind of harsh tho, and I'm working with a mini-board at the moment (don't worry, there's a larger one on another rig). So I added a switchable fixed hi-cut (low-pass) filter that can be toggled into either of two positions in the circuit from its slightly-off-center switch:

* right position to cut incoming highs, but preserve inverter created high harmonics
* left position to cut outgoing highs after the distortion section
* middle position is no high-cut filter at all.

Now it plays really well with others stacked in either direction with just a toggle.

This is likely to have a "permanent" (haha) position on the mini-board due to its versatility.
This has been a very satisfying project. Brain is temporarily at peace.

I'm now contemplating formalizing the new schematic in software and possibly attempting to prototype a new PCB to include the new components to learn how that's all done.

Oh yeah, POIDH. I'm sure you can spot it.