This Week on the Breadboard: BJFe Arctic White Fuzz

[szukalski]

Let's give this one a whirl:

 

[szukalski]

Built this one up tonight, it sounds great! Definitely purrs and roars as described.
Apart from the BJT being backwards (BC549 is CBE, not EBC), it went nicely.
I love myself a FF, and this one does a great job!

 

[Chuck D. Bones]

"Good news everyone!"
The four knob version is here.

White Knob: LEVEL - White Knob: TONE - White Knob: ATTACK - White Knob: FUZZ



I did my own thing with the TONE control network. Treble cut below noon, flat at noon and treble boost above noon. It will purr, growl, snarl or roar depending on the knob settings. I had 4.7μF for C4, but it got a bit muddy when ATTACK was dimed, so I reduced it to 2.2μF. YMMV. With FUZZ & ATTACK below about 10:00 it plays clean. Crank FUZZ and use your guitar's volume knob like you would with a Fuzz Face. With FUZZ & ATTACK dimed, it gets very mid-focused, to the point of sounding a bit like a stuck wah. I tried MPF4393, PF5102 & J113 for Q2. They all worked well with the same value for R8. The PF5102 has the most gain, although the only time it matters is when ATTACK is dimed. ATTACK is very touchy above 4:00. If you're only intersted in the high-gain end of the range, then I recommend C1K for the ATTACK pot. Similarly, C500K works well for FUZZ. We get all of the tones from the original Arctic White Fuzz and a bunch more with this setup. D1 can be any diode, or you can go with a 1N5817 in series with R14 instead. Q1 can be any high-gain low-noise Si NPN.

 

[music6000]

 

[mcgruff]

Every JFET needs to have its bias dialed-in. The best way to do that in this circuit is to tweak R8. I ended up with a 5.90K resistor. You could put a 3.9K and 5K trimmer is series in place of R8.

View attachment 27158

Will be building this soon with B550C/J113, and the 3k9 resistor + bias trimmer you suggested.

Bit of a noob though... can I check how I would measure the bias voltage while I'm adjusting the trimmer? Is this the voltage between the the circuit at [Q1 collector/Q2 gate/C3/R7] and ground?

 

[Chuck D. Bones]

Measure voltage at Q2-D w.r.t. GND. Adjust trimmer to get between 5.3V and 5.4V. After that, you can adjust the trimmer by ear if you like.

 

[mcgruff]

Q2-C is the source, right?

Many thanks I think I've got it now.

 

[Chuck D. Bones]

Nope, my bad, I should have typed Q2-D (drain). It's been corrected above.

 

[mcgruff]

Great

Thanks for all the work you posted on this pedal.

 

[cooder]

Here's my Arctic White aka White Out Fuzz v2 with attack control. Also the modified tone control network is a great improvement IMO, great stuff.

 

[Chuck D. Bones]

Sweet!

 

[Feral Feline]

Great graphic!

 

[HamishR]

Do I see colours of the arctic tundra? Does a snow leopard even live in the arctic tundra? I thought they lived in snow caped mountains. See, this is why pedal designers need to be more aware of big cat environments. Well, of most large mammals in general really.

Very cool enclosure though, despite the needless complications.

 

[Chuck D. Bones]

I see something else.

 

[zgrav]

adding a link to this geofx article from 1998 that discusses the fuzz face layout in detail.

 

[szukalski]

I enjoy the original so I am looking forward to trying the Boneyard edition!

 

[szukalski]

The build went well, really enjoy this pedal. v2 is a great evolution from v1, an immensely better pedal. One of the few things I have boxed this year!

[Sheepylove] Dall v2 - Celestial Engineering Average White Fuzz

It's been a while since I've done a build report, I've been doing a lot of building but not a lot of boxing. A big part of that is because I've been working on a few things, moving from DipTrace to KiCad, and playing with ideas for different faceplate designs. I think I have got to a happy place...

forum.pedalpcb.com

First build to get the new Sheepylove faceplate approach. Thanks Dave, this is a fun one.