The 1776 Unicorn Breath Buffer is based on the buffer circuit in the famous Klon Centaur but with a little something extra that makes it a really cool/handy little project.  I'll be going over the bare bones of why you would want a buffer in your signal chain and then what makes the Unicorn Breath unique

What a buffer does...

Everyone's heard the debate over buffered vs. true bypass pedals so I won't be going over that in this post. But general consensus is that true bypass is great, unless you have a bunch of cabling and pedals between you and your amp. The extended cable lengths (through cable capacitance and signal impedance) create a low pass filter that cuts off more of your high end as the cable length increases. A buffer near the beginning of your signal chain alleviates this issue by lowering your signal impedance which raises the cutoff frequency of the high pass filter. I won't go into any more detail on that here, but if you'd like to know more then leave a comment below. On to the board!

Unicorn Breath Buffer

There's a bunch of reasons I like the Unicorn Breath. It's designed around being a DIY project so there are some aspects of the board layout that are really geared towards the builder. That being said, I'm just going to go through my favorite things about it.

1. It's really small. The board itself is only 1" x 1". This makes it perfect for small boxes like the 1590A or 1590LB. It's also a great size for modding pedals like the Ernie Ball VP JR because it fits neatly inside the faceplate. 
2. It has the LED board mounted. I like this because I can just wire in the LED without thinking. Plus I can mount my LED without a bezel if I want to. 
3. Uses a dual op-amp. Most Klon buffers call for a single op-amp. This uses a dual op-amp pinout which is a more common part that you're more likely to already have (hooray for no special order parts!).
4. Voltage buffer. Your reference power voltage is buffered. This means that if you were to use the Vref on the board in another circuit, then the current draw wouldn't be an issue. It's not strictly necessary for this circuit, but it's a nice feature and uses the other half of the op-amp.
5. Extra ground ports. I like have extra places for ground so I can wire my power supply to the board as well as my jacks rather than having to snake wires all over the place. Plus most people don't wire a buffer as true bypass, so you can do all your connections to the board.  
6. Tight layout design. There's no wasted space on the board. All the components are neatly aligned with no strange spaces in it. It's just quite nice to look at both before and after it's been populated.

As far as sound goes, it's a buffer. Because it's IC based it's going to be unity gain (transistor buffers tend to have a tiny amount of loss). If you aren't currently running a buffer somewhere in your signal chain then build one of these. You'll get some high end back that you didn't have before which may mean tweaking your knobs a bit, but it also means you'll get consistent sound regardless of cables or number of pedals.

Overall, I really like this board. It's an incredibly useful circuit and the layout is just great. It can fit in a small box that won't take up a bunch of room on your board and your getting a great quality IC buffe. Plus, it's a fun, quick build due to the low parts count and layout.