Buffers: MOSFET, JFET or IC

[~nick~]

I’m looking to build a buffer circuit that’s as good as any class a, discrete, transparent, low noise buffer out there.

does anyone have any experience with buffer design and messing around a breadboard?
And ultimately would you make it mosfet, jfet or is an ic chip like the one in the Xotic Super Clean?

I want to put it in a drive pedal I’ve been brainstorming for a while now.

has anyone had any experience with the C-Buffer?

 

[jubal81]

Will the buffer only be active when the drive pedal is active or are you talking about buffered bypass?

 

[phi1]

I’ve built a Cornish buffer (same as C buffer) on vero a few times. I really like it, but I’m aware that my opinion may be influenced by all the crazy hype I’ve read about it, so sometimes I wonder if a Op amp, jfet, or bjt Buffer would be just as good (they are just buffers after all). I haven’t really tried a bunch side by side, I’ve just thought that the Cornish always sounds pleasing and musical in my experience.

Anyway, if you go with the C-buffer pcb, it’ll make for a nice, clean, pro looking build, and I doubt you’ll be disappointed in tone.

 

[~nick~]

I’m looking for an always on inside the drive pedal buffer no gain. But has to be isolated. Like the Suhr Buffer. If I could snag that schematic that’d be greaaaaat (and no, I won’t work on Saturday Bill Lumbergh.. ?)

I guess I could just source some VHF small toroids and use it with a simple buffer.

i found this schematic of an isolated buffer but I don’t think it was designed for a guitar signal. Pretty sure it’s aTV/Radio type circuit, but the idea is there..

“Why not buy a separate buffer pedal, or just get that Suhr” You ask? Well I’m heavy into multiple reverbs and delays on my pedalboard and I want to combine multiple drive and boost pedals into one (rather tall skyscraper of circuits) enclosure..

 

[jubal81]

You mean you need it isolated from ground? That Corp has chips that do that. Like to get a clearer picture of the whole project.

 

[~nick~]

All I know is I want to clean up any hum as best as possible when high gain and distortion or fuzz is in the signal. I’m learning as I go along and apparently I need an isolated output buffer at the end of my chain to accommodate the ground lift. I bought a Humboldt Simplifier and it can be pretty noisy. Just FYI what I’m working with...

So I think you’re right, a ground lift 1:1 iso transformer is probably what I want.

 

[~nick~]

also, The Rig Doctor at Vertex is talking about making a buffer. he talks about a dual buffer pedal with a iso out. he's trying to make it under 100 bucks so it might be pretty basic, but i think if he releases a diy schematic for this, that'd be dope as well. i need to do more research on iso audio transformers honestly.

 

[giovanni]

I don’t know what your setup is but I doubt that simply isolating the output will remove hum. Isolated outputs are usually necessary when splitting your signal in two paths (like for a wet dry) to avoid ground loops. The best cure for hum in general is a very very very high quality power supply. To check whether you need that I would try powering all your pedals from batteries and see if the hum level goes down? I hope that helps!