zVex Machine

Happy Fuzz Friday! Not sure how I haven't laid this one out before. Think of it like a mashup of a SHO and Tim Escobedo's Tripple Fuzz, and then repeated. Here's the schematic for reference. This one was drawn up based on an early 2000s model and the input SHO section I've modified to the newer version with a single 9.1v zener to protect the MOSFET instead of 2, 1N4148s in the layout below. I also added a pulldown resistor at the output (cuz I couldn't make it fit at the input lol). The 2 clipping diodes aren't known, other than they are large blue glass diodes with the markings "BKC" written on them, so socket and experiment.

zVex '59 Sound

zVex's new '59 Sound looks to emulate an overdrive '59 Fender Bassman amp and is essentially a tweaked Box of Rock. I've left out the boost section (which is essentially a SHO after this circuit), but can be easily added with the old SHO layout here on the blog.

Also, there's another installment of the DIYLC tutorial up on YouTube today. I actually am not using DIYLC all that much in it... 

zVex Super Duper 2-in-1

This is a pretty handy expansion of the zVex SHO booster. It stacks two SHOs together and adds a master volume control. This is laid out so the board is vertical in a 1590B oriented like the original.

Zvex Fat Fuzz Factory

For Fuzz Friday, here's a layout for the Fat Fuzz Factory in a 1590B in a more traditional orientation. All pots are board mounted as well as the Fat Switch. For C1 and C2 you'll probably want to experiment with values. Using an on/off/on switch gives you an extra option over the original. 3.3uF is a good place to start with one of them. Just a note, whatever value you chose will be in parallel with the existing 100nF cap. Thanks to p0mp0 for sending in his layout.

Zvex Mastotron

Happy #fuzzfriday, everybody. The Mastotron is a heavy silicon fuzz and a variation of the Wooly Mammoth. It can produce a wide sonic range from 8-bit sounds to complete wall-of-fuzz tones. I've drawn this up to fit in a 1590B more conventionally than the Zvex way. You can use PCB-mount right angle pots, mounted from the solder-side of the board. 

I'm going to try and start including drilling templates with layouts that have board mounted pots (or at least the right angle kind). As I have time, I'll be going back to previous layouts with board mounted pots and creating templates for them as well. You can find them in the new Drilling Templates tab at the top of the page. You can find a 1590B drilling template for this effect here.

Zvex Fuzzolo

The Fuzzolo is one of the newer Zvex designs in a 1590a box. It's a stripped down Woolly Mammoth with a SHO added to the end, so it's got a huge fuzz sound. In production versions, there's a moveable jumper internally to go between active and passive pickups. You could use a SPDT switch to accomplish this, and make it easier to switch between the 2 modes, or you could eliminate the 2 input resistors (750Ω and 39k) and use a 50k pot as a pre-gain control. The PW (pulse width) pot pans between a square wave and a wide/narrow pulse width. Like the original, this should fit nicely in a 1590a enclosure.

Zvex Wooly Mammoth

Looking for a Wooly Mammoth but don't want a sideways 1590b on your pedalboard? Here's the Zvex bass fuzz laid out for board-mounted right angle PCB pots.

Zvex Box of Rock

This layout is for the distortion side of the Box of Rock. The Boost side is just a SHO. I've laid this effect out for top mounted pots like in my other Zvex layouts and should fit vertically in a 1590B. Pots are 1.1 inches (28mm) apart.

Board dimensions: 3.2 x 1 in. or 81.3 x 25.4 mm

Zvex SHO - Crackle Okay

The Zvex Super Hard On has become one of the sought after boost pedals today. Derived from the preamp section of a 60s recording console, the SHO uses negative feedback to control the gain (which is what gives it the crackle when adjusting the knob). It's capable of being a clean boost and adding some sparkle to your tone, or pushing your tube amp to break up and creating a great overdriven sound.

If you want to add a master volume control to it, remove the 47k resistor and use a 50k pot. Lug 3 to the Out pad, lug 2 becomes effect out, and lug 1 goes to ground.

Zvex Wooly Mammoth

The Zvex Wooly Mammoth is a Fuzz Face derivative designed for bass, but sounds awesome on guitar as well. For this one I've laid it out for on board pots oriented like the originals. On the PCB I added an LED and LED resistor for on/off indication. As with my layout for the Fuzz Factory, this layout is designed for the pots to be mounted on the component side of the board.

ZVex Fuzz Factory

Here's my take on the ZVex Fuzz Factory. The originals have the pots mounted to the board as well, but ZVex uses the little square pots which are more expensive. I wanted a layout that used regular 16mm pots, which are easier to come by and what you probably already have in your parts stash. Q2-3 originally were AC128s, but any PNP germaniums should work fine. I believe ZVex has used a variety of different germaniums over the years. Hfe ranges should be around 70-100 and 100-150 respectively (much like a Fuzz Face).

For what it's worth, most of my layouts with onboard pots are meant to be mounted from the solder side of the board, like this:

You can do the same for this layout, but it's designed for the pots to be on the same side as the rest of the components, like this:

This way, the board will be vertical inside the enclosure, and the controls will be aligned like the original: