Project: Simple Buffered Splitter

[culturejam]

This is a very simple buffered splitter project. You can use it to create two equal outputs for your guitar or another pedal. This is handy for running a stereo amplifier setup, splitting a single signal into two effects pedals, or any of several other applications in which you need to have two equal, buffered outputs.

The circuit consists of a simple transistor input buffer that feeds a pair of parallel op amp-based output buffers.

This is tested and working just fine. Ready for etching!


More info (and transfers) is in the project PDF:
http://www.forrestwhitesides.com/files/ ... litter.pdf






Here are pics of the prototype (not my neatest work inside or out, but good enough for testing):

[Toonster]

Wow thanks! I think this will come in handy sometime

[Jero]

Another thing to add to the list...

[eatyourguitar]

have you seen the lahle p-split. its the same idea but it doesn't run the + signal through any circuits at all. just isolates the ground so no ground loops between amps. for the $160 they are charging I would be interested to know whats in it. it might even be simpler than this one.

[culturejam]

have you seen the lahle p-split. its the same idea but it doesn't run the + signal through any circuits at all. just isolates the ground so no ground loops between amps. for the $160 they are charging I would be interested to know whats in it. it might even be simpler than this one.

No, I haven't seen that...until now.

They say it's a passive splitter. But then they also say it has a phase reversal switch. I'm not sure how they would invert the phase of the signal with out some kind of active circuitry.

I'm a DIY dude by nature, so naturally I don't think it's worth the price tag. But then again, sometimes it's nice not to have to make everything.

[multi_s]

just curious, what is the advantage of buffering an opamp with a transistor stage?

They say it's a passive splitter. But then they also say it has a phase reversal switch. I'm not sure how they would invert the phase of the signal with out some kind of active circuitry.

you could do this with a transformer(still passive). thats probably how they isolate the grounds as well. just guessing.

[culturejam]

just curious, what is the advantage of buffering an opamp with a transistor stage?

There's some discussion of that in this thread:
http://circuitworkshop.com/forum/index.php?topic=626.0

you could do this with a transformer(still passive). thats probably how they isolate the grounds as well. just guessing.

I'd like to see more about how this works. I'm still pretty green on transformers.

[elbandito]

How would I turn a PCB layout into a perf layout? I have no way to (or knowledge of) etch(ing) boards.

[nbabmf]

Just bend the legs of the components to the same path as the PCB layout. Nine AND A HALF times out of ten, the leads are long enough to reach.

[Jero]

Hey FW, do you have a vero for this made up? I'm going to work on one if not. Also, is there a way to add a bypass switch so that one could remove the stereo option on the fly?

I wonder what running the stereo out of a delay into this would be like...better yet, what running 1 guitar into 4 amps would be like

[culturejam]

Hey FW, do you have a vero for this made up? I'm going to work on one if not.

No, I don't have a vero layout. Go right ahead.

It was also noted in another thread at Circuit Workshop that the 10M resistors could be much lower (like even 100K) and have the same net effect.

Also, is there a way to add a bypass switch so that one could remove the stereo option on the fly?

Do you mean going from having both buffered outputs to just one buffered output, or do you mean bypassing the circuit as a whole?

Either way, it can be done just with a 3PDT (I think).

I wonder what running the stereo out of a delay into this would be like...

Well, the input is mono, so that might not work. Unless you mean running one side of the stereo out into the splitter, which could open up some interesting possibilities.

If you had your dry signal going into the splitter, and then one output going to Stereo Delay #1 and the other output going to Stereo Delay #2, you could run the delay outputs (4 total) into 4 different amps. That would be cool.

[Jero]

It was also noted in another thread at Circuit Workshop that the 10M resistors could be much lower (like even 100K) and have the same net effect

Thanks for the reminder. I was reading those notes at CW a couple days ago.

Do you mean going from having both buffered outputs to just one buffered output, or do you mean bypassing the circuit as a whole?

Either or. I orig meant going from both outs to one though.

If you had your dry signal going into the splitter, and then one output going to Stereo Delay #1 and the other output going to Stereo Delay #2, you could run the delay outputs (4 total) into 4 different amps. That would be cool.

Exactly that. If possible, would also be neat to have the wet/stereo from the delay go into the splitter, then you could have 2 wet signals each to their own amp and one dry.

Another potential use for this I see is pseudo-blend/mixing. An example: Run guitar>fuzz>split out1>amp & split out2>modulation>amp
You can now blend your fuzzy sound with the fuzzy delay sound. For some clean blend action you could obviously skip the fuzz and have one split to a clean amp and the other to an effected amp.

Ok, that's enough thinking out loud for now.

[elbandito]

Hey Jero, if you end up making any vero/perf layouts, would you mind linking them here so I can check them out too?

[Jero]

Yea, any layouts will be posted. This will be my first vero so bare with me. It's a fairly simple circuit in the scheme of things so it should be somewhat easy...I hope