Signal Splitter for Guitar Recording

[AudioEcstasy]

I'm going to be recording some guitars soon and wanted to get a general consensus. I like to split the signal, one to the amp and another for direct/modeling. Usually I just use a Boss Tuner and that's worked fine. My question is its effect on the tone, would it be worth it to build a dedicated splitter?

[Kipper4]

I made an ABY exactly for this purpose
i wanted to be able to
A record a dry signal straight through the interfaces line in.
B route to a real amp and record it too.

So i made an ABY with led indicators and a buffer on the input.
I had a wire failure so rehashed with a dual output buffer.
Both had a hum issue i was unable to cure.

So i set about making an op amp buffer with enough gain to record to line in.
Enough attenuation to use as a reamp box coming back out of the interface
and more importantly as little hum as i could live with.

I'll post up a pic of my opamp buffer design ( I had to figure out one from bits i gleemed on the net as i didnt find what i was looking for straight off google)

https://www.dropbox.com/sh/7ma9n53c5jqdgsr/d-0TvwYXDL#f:Buffer%20OPAmp.jpg

I hope this helps if you need more info i can put up a link to the ABY wiring i used.

[artifus]

http://www.jensen-transformers.com/apps_sc.html#musical

[therecordingart]

I'm working on an all-in-one buffered splitter/reamp box. You can split your signal in two ways via an opamp buffered splitter or use it as a line-to-amp device via an Edcor transformer.

[Kipper4]

Which edcor tanny are you using?
Have you a schematic for this box please?

[moosapotamus]

My question is its effect on the tone, would it be worth it to build a dedicated splitter?

Sorry to answer your question with a question, but...

What are your ears telling you? Are you wishing that your "tone" sounded different somehow? If you are relatively happy with your current sound, it might be difficult to say what "better" really means.

OTOH, if you think you might be loosing some signal level, clarity, definition, dynamic range, or whatever, a decent preamp/splitter might be just the ticket.

Either way, it's fun to build stuff!

~ Charlie

[Paul Marossy]

http://www.jensen-transformers.com/apps_sc.html#musical

The only thing with those Jensen transformers is that it costs like $75...

[therecordingart]

Here is a mash-up of the NYDave Reamp and a couple of opamp stages. The feedback resistor values are random on this schem, and you can do the math (POT2/R7 or POT3/R8) for your wanted gain. My current unit is just a pair of buffers. There are some errors in the schem (Sleeve of J1 is floating instead of grounded.

[mremic01]

http://www.muzique.com/lab/splitter.htm

I built this with four outputs. One of the outputs is on a 3pdt stomp switch. The bypassed signal sounds exactly like the buffered signal, and it'll drive all four output at once.

[artifus]

The only thing with those Jensen transformers is that it costs like $75...

just wind your own... 

just posted the link for reference, principles and theory of operation remain the same regardless of component manufacturer. a transformer may not be required depending on your set up and recording environment - power supplies, grounding, etc. - hum may be an issue otherwise. or not.

[R.G.]

Sometimes I get daunted at the sheer number of posts on buffers and splitters. The concepts are simple, but they never seem to get out in to the greater mass of folks interested in musical electronics.

Splitters are only necessary when (1) one of two or more loads may impair the signal to the other loads and/or (2) splitting is needed to solve hum and noise issues.

If you have high impedance loads - like most guitar amps - and there are no hum issues with connecting their grounds, an explicit splitter is not needed. Full stop.

If one (or both, or all three, or ...) of the amps has some kind of loading issue which changes the signal level or frequency content to the other outputs, some kind of splitter, usually a buffered splitter, is needed to keep the signal from being polluted by that load.

If one (or both, or all three, or ...) of the amps causes hum issues with the others, then a hum isolating splitter is needed.

A passive splitter generally can't solve the first issue, at least not well.

A passive isolating splitter generally causes problems with frequency response while solving hum and noise problems, again fouling the first criterion.

And active splitter to isolate loads from one another is generally needed to keep the signals pure. These are generally purely buffers. Tacking another adjective onto "buffer" like "ultra-buffer", "mondo-buffer", "gad-zooks-buffer", etc. doesn't help, and in general is an exercise in advertising.

Buffers are (or should be, if designed by someone who knows what they're doing" devices for presenting very little loading to a signal, and then being able to drive heavier loads with an accurate image of the input signal. That's all. The devil is in the details, and doing a really good, high input impedance, low output impedance, low noise, wide frequency response, stable, quiet, reliable buffer can be tricky; this depends on how good you demand the image of the signal out of the buffer to be.

Isolating outputs generally requires at least one buffer to drive a transformer which provides a galvanically isolated (which means "a DMM says the resistance between them is 'way over anything it can measure") output, because a transformer is an abusive load to an unbuffered guitar signal.

Guitar amps commonly cause hum and noise issues because they are not well designed by today's standards for either keeping AC hum and noise out of their grounding system, or for rejecting input noise.

That's really the short course on buffers and splitters for guitar signals.

[Kipper4]

Sounds like we could do with a sticky on Buffers.

[R.G.]

Not a bad idea.

Technology is hard enough without people using technobabble to confuse things. Buffers are not magic, just the application of a tool. I'd be happy to write up some stuff for a sticky.

[bluebunny]

...or the Wiki?

Hmmm...  "sticky tricky wiki" anyone??   

I'll get my coat...   

[Kipper4]

Taxi for Bluebunny

[Paul Marossy]

AMZ has a nice page about buffers: http://www.muzique.com/lab/buffers.htm