Fulltone 2B

 Happy 2022, everyone! Here's a buffer/booster from Fulltone. Engaged it's a booster with an interesting controllable germanium soft clipping setup, and when bypassed the diodes and gain control are shorted, creating a buffer. If you're just after the boost and want to skip the buffered bypass, just ignore the two Bypass pads and wire it normally. The original uses a 3PDT still for bypass, but you should be able to get away with a DPDT (just wire the bypass pads to lugs 1 and 2 of a DPDT, LED- to lug 4 and lug 5 to ground). Discussion and schematic over on FSB.

Fulltone OCB

What's the OCB you ask? It's the bypass buffer circuit from the new version of Fulltone's OCD. It allows you to switch between regular true bypass and buffered bypass. There are 2 versions: The first (smaller) inverts the phase of your audio signal when engaged (in bypass mode phase isn't inverted). The second (larger) adds an extra inverting transistor stage so that the phase of the output signal is the same as the signal coming in. If you've built an earlier version of the OCD in the past, you can add the 2nd board to make it into the newer version.

Barcus-Berry 3000A

Stumbled across this schematic on FSB. It's a buffer/EQ/preamp for peizo pickups, specifically all Barcus-Berry electret microphone systems. I figured most would be building this into an instrument and not a pedal, so all the pots are off-board. If you're planning on running it only off a 9v battery, you cab get away without the power filter cap (47uF) or the polarity protection diode (1N4001).

Inverting Phase Buffer

Got a request for a dual buffer that inverted the phase of the signal. Found this post from Parasit Studio and used it for the basis of this design. I added polarity protection, power filter cap, and output caps. You can use either dedicated jacks for the in phase and inverted phase outputs, or use a SPDT toggle connected to a single jack and use it to select between the two outputs. (In phase output pad to lug 1, output jack to lug 2, inverted phase output pad to lug 3.) Should prove to be a handy utility. Single and dual versions below.

MI Audio Boost 'n' Buff V1

The Boost 'n' Buff is a simple little booster that doubles as a buffer when it's turned off (so it's not a true bypass effect). You should be able to squeeze this one in a 1590A. The FSw pads are for the bypass footswitch. If you want to build the second version of the Boost 'n' Buff, add a B20k to the output as a volume control.

Tiger Pre-Amp

If you're a Dead Head, you'll probably be interested in this one. It's the pre-amp from Jerry Garcia's Tiger guitar used from '79-'89 and built by Doug Irwin. It's a unity gain buffer to prevent signal loss with long cables. It can be built into a guitar like the original or into a 1590A. Other single op-amps can be used instead of the LF356N (TL071, NE5534, etc).

Ceriatone Klein-ulator

Got a request for this one. It's a effects loop buffer that's a solid-state version of the Dumbleator effects loop buffer. It's equipped with an internal charge pump that converts a +9v supply to +33v. Very useful for keeping your effects loop free from signal-loss. Since it runs at a much higher voltage than most effects, make sure your components are rated at at least 50v. Also the 10Ω resistor off the +9v pad should be 1/2 watt or higher.

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.

Cornish G-2

Happy Fuzz Friday, everyone! As promised, here's my layout for the Pete Cornish G-2. The circuit is essentially a Big Muff (with a few different component values) with a simplified tone stack and input buffers. It's not quite as fuzzy or distorted as a typical BMP but more of a heavy overdrive. Though it can get fuzzy at higher Sustain levels. There is a bit of uncertainty over the type of diodes used in the clipping stages, so socketing is a good idea here. 1N34s or 1N60s are a good place to start.

As I mentioned earlier this week, I've also laid out the bypass buffer with a board mounted footswitch. It's a little too wide for a 1590B, but this and main circuit layout will fit very nicely in a 125B enclosure. 

If you're building on perf and want to include the bypass buffer of the original you can use the Cornish Buffer layout and wire it like this:

Buffered Bypass

Prepare for a bit of rambling: I was looking through the de-goup thread for the Cornish G2 over on Freestompboxes.org and was intrigued by the buffered bypass switching that's used on that pedal. (Before people bombard me with requests for the G2, don't worry it's coming.) Original G2s have individual PCBs for the footswitch, the bypass buffer, and the effect. Surely the first 2 can be combined, right? So I drew up the Cornish buffer with a board mounted footswitch (which I will share when I post the G2 layout), but it was too big to fit in a typical 1590B with the footswitch centered in the enclosure. Then I got to thinking about replacing the buffer circuit with one that took up less space. So I drew it up with the input buffer from the Klon and it will fit very nicely in a 1590B. This uses a board-mounted DPDT footswitch (I bought a bunch from Tayda a while back) and the on/off indicator LED can be mounted to the board as well.

I verified this over the weekend and here's a few pics of my build.

Cornish Buffer

Got a request for the Pete Cornish Buffer in dual form like the one I did with the Klon Buffer. So here's both a single and a dual Cornish Buffer. The original uses a 1N5401 for polarity protection, but a 4001 or similar will work too. And you can probably get away with a small value on the power filter cap (220µ).

Dual Klon Buffer

In an effort to make my own personal pedal board better, I'm building buffers at the input and output of my signal chain. As space and DC jacks are always a premium, I thought to build a dual buffer in a 1590A enclosure. The Klon Buffer is great and since it only uses half of a TL072, I figured I could just use the other half for the second buffer. It's a little tight depending on the jacks you use, but the board is small enough to mount vertically to an inside wall of a 1590A while the wall opposite can mount the 4 input/output jacks. Here's my drilling template to better illustrate.

And here are a few pics of my build.

JHS Little Black Buffer

Here's a simple buffer from JHS. It really only uses one side of the opamp (why not just use a TL071?) and the extra resistors on the other side are just to meet the manufacture's specs for an unused side. I couldn't find a schematic for this one, but drew one up from lvlark's vero layout. I've added polarity protection and extra power filtering to the layout.

Stupidly Awesome Buffer

Here's a well designed buffer by Martin from SoulSonic FX. Use it as a stand alone buffer or as an output buffer in another pedal. Should fit easily in a 1590a enclosure.

Simple JFET Buffer

Here's a simple one for your Saturday. As the name implies, this is a simple buffer based around a JFET transistor. This layout follows the schematic from Jack Orman's great article on Basic Buffers. Thought this would be useful if you want to add an input buffer to an existing pedal or to a project that doesn't have one.

Klon Buffer

Who doesn't love a Klon, right? Here's the buffer stage of the Centaur. The original Klon uses one side of a TL072 for the buffer and the other for gain stage. If you're building the just the buffer, you can get away with a TL071. I've laid out a perf and PCB for each.