Taking a split mic signal into a guitar combo + impedance

[Tubthumper]

Hi all, apologies if this post is a little naive.

I'm trying to take a single mic signal and split it two ways so that I can feed two distinct destinations: one of the splits running into an outboard mic pre, then into Tools, the other split fed into the 1/4" TRS jack plug input of my valve guitar combo (so that I can take a line out from the combo into Tools AND mic up the combo's speaker and run that into Tools also.

I'm hoping that someone can help me with three questions:

1. Can someone recommend a good splitter box from which I can take the mic signal and split to the preamp + guitar amp?

2. Will the output signals that come from the splitter be degraded in any way, i.e., will they be identical, quality-wise, to the input signal?

3. Is there a problem with running a mic signal into a guitar amp in terms of impedance, and if so, is there some way of converting the mic signal impedance to match that required by the guitar amp?

Thanks, all the best,
Greg

[David Kulka]

Yes, impedances and balancing would probably mess you up. I think it would be simpler, cheaper, and better to put a "Y" adaptor on the output of your mic pre. One side goes to Protools, the other side goes to a rather severe pad (40-60db?) and then into the guitar amp. If your amp has an effects loop or a line in you could probably skip the pad, or use one with just 12 db or so attenuation.

With the mic pre as *the mic pre* you'll have more control and a much cleaner signal. And if you need phantom power, the other way would be really difficult.

Only catch is, your pre out is probably balanced and your guitar amp in will be unbalanced. It's not totally kosher but you can probably get away with just using hi and ground from your Y adaptor to feed the guitar amp. If you hear ground noise or something strange on the Protools side, a small transformer on the guitar amp side would probably cure that. But it would still be easier than doing it the other way.

[Tubthumper]

Thanks for chiming in David.

[tINY]

You blowin' harp into that mic?

If so, iit's probably a high impedance mic. Any guitar splitter will work for that.



-tINY

[Tubthumper]

Originally Posted by tINY

You blowin' harp into that mic?

If so, iit's probably a high impedance mic. Any guitar splitter will work for that.



-tINY

tINY,

Nope, mostly vocals, acoustic guitar, mono drum overhead, and percussion through either a LDC or dynamic mic.

My thinking is: if I'm attempting to introduce some grit into my somewhat clinical digitally-recorded tracks, why not take a split during tracking and process through my class A valve guitar combo rather than trash later using Sansamp or similar plugins?

Just experimenting really.

[Schexnayder]

not to take a turn away from the subject at hand, but in a somewhat related way this has peaked my curiousity...

if you were to split that mic to two separate mic pre's (maybe one for a FOH and another for a multitrack)...how would you treat phantom power...do both pre's send +48?

[tINY]

Classically, the transformer-coupled splitters had one split that was DC-coupled to the mic. That was the one that supplied the phantom power. You never want two phantom power sources hooked up as strange things can happen. since the feeding resistors are pretty big, you are not likely to hurt anything (except sound quality), but it is not a good idea.

As for running things through a guitar amp: If that sculpted, band limited tone is what you want for a mic, you probably should do the line-level-output-and-pad method. It shouldn't change the quality of the feed directly to the recorder if done right.



-tINY

[krucka]

dude!, first of all i don't know what your budget is like, but check out the Little Labs PCP INSTRUMENT DISTRO REV 3.0 it retails at $1100, but you can find them for around $900. it does exactly what you're wanting. you can check it out here -> http://www.littlelabs.com/pcp.html