CMAT Mods Signa

Got a request for this one. It's a barely modified Tube Screamer with a clipping switch to go between silicon and red LEDs. The switch is a SPDT on/off/on by the way. Gearmandude really seems to like it.

Smallsound/Bigsound Team Awesome! Fuzz Machine

For Fuzz Friday here's another cool design from Brian at Smallsound/Bigsound. It's a unique silicon/germanium hybrid fuzz box with all kinds of options. This was traced over on Freestompboxes and Brian was kind enough to chime in and shed a little light on the circuit. There have been a couple versions of this circuit with both PNP germaniums with a charge pump and this version with NPN germaniums. The dip switch is there to give the option of bypassing the input buffer. For the buffer to be on, switch 1 down and 2 and 3 up. To bypass the buffer, switch 1 up and 2 and 3 down. There are a couple question marks around the circuit still, specifically 2 diodes (which are probably schottkys) and one larger capacitor (probably 330nF), so socket things and experiment. It seems to be a very tweakable circuit, and it work well on guitar and bass.

 

Demeter Compulator

Here's a really nice optical compressor from Demeter. It offers vintage studio compression that's very transparent and a fairly simple simple build as well. The trimpot sets the gain of the compressor's preamp stage. If the signal is distorted, turn down the trimmer till it's clean. Here's the schematic for reference.

Menatone None More Black

Here's the None More Black from Menatone. It uses cascading JFET stages to produce a high gain distortion tones of the 80s all the way to modern metal tones. There are apparently some versions with and without a charge pump to run at 18v off a 9v supply. I had room for the charge pump, so I included it.

Death by Audio Robot

For Fuzz Friday, here's another wild and wacky one from DBA:

The Robot is a low fidelity 8 bit pitch transposer with absolutely no feelings what-so-ever. It is completely synthetic and transforms any input into a spuree of resynthesized robot jargon.

Originals need a dedicated power supply as the HT8950 chip runs off 2.4-4 volts and the power section of the original will not play nice daisy chained with other pedals. To make it a little more user friendly, I've altered the power supply to use a 3.3v regulator (LM1117V33C or similar, though watch the pinout). Here's my modified schematic:

Note: I've also included 4 extra pads on the PCB layout in case anyone wanted to do the mod lvlark describes here.

Valve Wizard Small Time

Here's Valve Wizard's take on the PT2399 delay. It's very similar to most PT2399 delays out there, with a dual op-amp providing input and output buffering. This was designed with the tails function and it uses Valve Wizard's usual J112 switching. Here's his original schematic and explanation of the circuit. You can also use a DPDT footswitch for bypassing, using one side to turn the delay on/off and the other for LED indication. I've included 2 extra pads on the PCB layout for this function. If going this route, don't populate the J112 along with the 1N4148 diode, 1k and 4.7k resistors, and 10µ capacitor round the J112.

Walrus Audio Mayflower

Here's the Walrus Audio Mayflower, which is essentially a hybrid between the Tube Screamer and the Timmy (which has its roots in the TS already). Originals use a second dual opamp for buffering the voltage divider, which in this instance seems to just be unnecessary, so I've omitted that.

Devi Ever Vintage Fuzz Master

Here's a cool one from Devi Ever for Fuzz Friday. The Vintage Fuzz Master is only slightly different than the Soda Meiser and both can be built on the same board. The only difference is the orientation of the PNP 2N2907A transistor. I've also included 2 switches for the Chaos and Noise mods. If you don't want to include the switches, just jumper the switch pads.

Menatone King of the Britains

Here's a Menatone design that emulates a Marshall JCM800. Like many Menatone circuits, the King of the Britains has had several iterations over the years. For this layout I went with the 6-knob version (and is essentially the same as the Electrictabs JCM800 emulator). I've laid it out specifically for a 125B enclosure with all the pots board mounted. Here's the schematic for reference. I would have liked to included trimmers for biasing the J201s, but there just wasn't enough room. So it's probably a good idea to socket the resistors feeding the drains and reference the schematic for voltages.

BearFoot FX Baby Pink Booster

Here's a cool little booster from Bjorn. Fairly typical JFET boost but the way the originals are wired, when the effect is bypassed, it's buffer. This layout reflects that original wiring, so wire the In pad to the input jack, Out pad to the output jack, and use a DPDT footswitch. If want to wire it for true bypass, jumper the 2 switch pads at the top of the board and omit the 150k resistor going from lug 1 of the Boost pot to ground. Or you can wire up a SPST switch to go between buffer and boost. Lots of options with this little circuit. Works well off 18v too.

HipKitty Oxblood Distortion

 Here's your Fuzz Friday fix. I'm calling it a fuzz anyway since it's just a modded Fuzz Face with an input buffer and a treble cut control at the output. It's supposed to give the boxy sound of a cranked AC15. Here's HipKitty's description:

The Oxblood Distortion was designed to emulate the tone and response of an old Vox AC15 with added gain at the input stage. Unlike other Vox-like pedals which emulate the tone and response of the Vox AC30, only the Oxblood Distortion emulates a boosted AC15.

Unique to the Oxblood Distortion is it's ability to make a "large" amp sound "small" and in hyper-drive with the tone of the AC15.

Also unique to the Oxblood Distortion is it's controlled output. While other distortion pedals use greater than unity gain at output to alter the user's amplifier input stages, the Oxblood Distortion does not. This keeps the true tone and response of the effect intact throughout the initial preamp stage of the amplifier in use.

Mad Professor Little Green Wonder

I feel like in the past few months I've done a ton Tube Screamer variants. Well here's another one, but one of the more interesting ones I've seen. Bjorn designed this one for Mad Professor and utilizes a dual-gang pot for the Body control that affects both the treble and bass response. The IC was originally a LF353, but that was changed to the TLC272CP as it was more readily available and worked at lower voltages and breaks up easier. The only schematic I found online was a little difficult to read (it was hand drawn) so I've drawn that up in Eagle as well. Pots are board mounted and will fit nicely in a 1590B.

EchoPlex Preamp

The EchoPlex Preamp emulates the input stage on the old EchoPlex EP-3. It provides up to 11dB of gain and is mostly used as an always on pedal to sweeten the user's tone. If you want to add the volume control, use a 500k pot and connect lug 1 at the junction of the 100n cap, 220k and 100k resistors, and run lug 2 to ground. This also works really well when running at 18v. Schematic for reference can be found here.