"Aberraton" Fuzz (Aberration)

[joelorigo]

I had not been able to do any pedal building for about 6 weeks due to work, travel, Covid and more work, so this week I was able to finish 2 that were in progress. One was a second Mahayana that I built for my brother in law because he liked the one I made for myself so much. The other was this.

I bought a lot of 10 MP38A transistors from an eBay seller in Ukraine for the Ge one, and had a random selections of ones on hand to try for the silicon pair. I also finally got a TC1 and was able to select a MP38A that is close in hfe (about 74) to what the build doc says (79). For the silicon ones the build doc says 312 and 318. The closest to those numbers I have is a BC183B that is about 317 and a BC018B that is about 228. So the only real difference I have is one of the silicon transistors is significantly lower than one in the original model. (Or is it significant? I also have ones even lower and ones higher. What would higher or lower gain values do?)

I biased to about 4.5 and it sounds good! Pretty much like the demos I think. I'll compare more later. And also adjust the bias and see what that does.

Then after I tightened all the nuts and put the knobs on, I realized I spelled "Aberration" wrong. So I have a "Aberraton" fuzz. It's been that kind of day today. But, I'm happy to have the pedal done and that it works!

 

[Bret608]

Great looking build nonetheless! I would doubt having those Si transistors close in gain would really change the sound much, so if it's sounding good, slap that lid on and play!

 

[joelorigo]

Great looking build nonetheless! I would doubt having those Si transistors close in gain would really change the sound much, so if it's sounding good, slap that lid on and play!

Thanks!

I did pull the "lower than spec" one and replace it with one that was "higher than spec" (about 380) and it has more gain and is a bit "throatier." I think

Also, I messed with the bias trimmer and decided for this one that about 4.5 sounded the best. At more extreme settings on both directions it still sounded cool, more gnarly and gated. I just have other fuzzes already like that.

And that leads me to note that one thing about this pedal is that after twisting the knobs, I don't think there bad setting on it.

 

[joelorigo]

I can't leave well enough alone so I bought 25 BC107B transistors from an eBay seller and put in the 2 that tested closest to what the build doc lists. The are 1 digit off so basically the same. And I re-tested my MP38As and found one that is only 4 off the one listed in the build doc. Does it sound different? Less gainy and less "throatier." I think

 

[Feral Feline]

Which do you prefer? Stock or Gainy-Throatier?

 

[joelorigo]

I might like the gainy/throatier, so I think I'm going to try it back with one of the higher hfe BC018B ones. With the "stock" values it might be more "distortion-y" than "fuzz-y" sounding, if that makes sense. Not bad though, it still has no bad setting.

 

[CanadianDave]

I might like the gainy/throatier, so I think I'm going to try it back with one of the higher hfe BC018B ones. With the "stock" values it might be more "distortion-y" than "fuzz-y" sounding, if that makes sense. Not bad though, it still has no bad setting.

Agreed that there’s no bad settings.

 

[joelorigo]

I did remember after I posted yesterday that in the "stock" values, I find it more "useable" or "versatile" when rolling down the volume on the guitar. I have only been using a Strat btw for all my playing so far, so obviously P90s or humbuckers will give different results.