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.- 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.
- 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.
- 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!).
- 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.
- 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.
- 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.
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.
Sweet blog! So this is the buffer circuit I should purchase for the VP jr mod?
ReplyDeleteHi Michael. Thanks for checking it out.
DeleteFor the VP JR mod, you can use just about any buffer circuit you like. I personally recommend this buffer for the VP JR mod because the PCB is so compact that it's easy to fit inside the enclosure. Also the additional ground ports are really useful.
If you do buy this board then you can leave off R6 and the LED since you'll be wiring those in a specific way according to the VP JR mod.
Also, feel free to let 1776 effects know that I sent you there way. I'd very much appreciate it. Let me know if this was helpful and feel free to shoot me an email with any other questions: prentisseffects@gmail.com