Turning A Buffer Into A Spluffer

[pyreweb]

Hello, I am worried that this will be my most naive question yet. How would I turn a buffer into a splitter and a buffer? I am looking at the Peter Cornish buffer and have built two of them, am I correct in thinking that if I feed the guitar signal to both input wires it will work as a spluffer with no loss of signal level? Or would I need to split them at the output instead?

Many thanks.

[induction]

You're correct. Most splitters are just multiple buffers being fed by the same input. Buffers have high input impedance and low output impedance, so connecting multiple buffers to the same input won't appreciably increase the load on the signal. Here's something to read, if you're interested.

Using a Y cable or something similar to feed two identical buffers should work fine, though the input impedance will reduced by a factor of two. It will probably still work fine, though.

It is possible to split the output of a buffer as well, but it's trickier. In that case it's important to know what the outputs will be connected to if you want a good design. Splitting at the input is much less finicky because the outputs can't see each other.

[pyreweb]

That is very very helpful, thank you. So if a buffer is the easiest way to split a signal, is it still the method you'd use for splitting a signal from an active bass (for example for clean and distortion blend, or a tuner out), even though (as I understand it) active instruments do not need buffers?

Many thanks.

[induction]

You may be able to passively split the signal from active pickups. It would be essentially the same thing as splitting after a buffer, with the same possible hazards. The inputs of whatever you send the signal to will be able to see each other (impedance wise), and there may be some interaction. For example, if one of the circuits has an input volume and you turn it all the way down, the other circuit may go silent as well. A lot depends on the circuits in question. Wouldn't hurt to try it out and see if it does what you want.

An active splitter will work just as well for active pickups as for passive, as long as the supply voltage is high enough to avoid clipping the splitter. Electrically, it would be equivalent to two buffers in series, which is generally harmless.

[pyreweb]

Excellent, I will look into what devices the multiple outputs will be connected to next, but I suspect that an active splitter will be the best way to go, then I can use the same input and setup for active and passive instruments. I will just include a charge pump or something to boost the voltage. Thank you for your responses.

[induction]

Sounds reasonable. Honestly, the charge pump probably won't be necessary. I only mentioned the supply voltage because I don't know how loud your active pickups are, and there is a small possibility that they could clip the buffer. It certainly won't hurt anything to include it though. If you want to test it out, play your actives at top volume through one of the buffers you already built. Play with no distortion and no other effects. If it doesn't clip, you won't need the charge pump.

Good luck with your project.