The GuitarNutz stance on Re-amps?

[ashcatlt]

Seems like every other day a thread pops up on the other forum I frequent regarding re-amping.

This is where you record a signal, then run it back out to a guitar amp and mic it. There are various reasons you might want it. You might record a DI signal from a bass or guitar so you can pick and choose amps at a later date. Maybe you want to add a little crunch to a snare drum track. Or perhaps you'd like to run your vocals through your favorite stompbox.

Anyway, most people seem to think that this process requires a fancy box called a Reamp^®. Apparently, you can substitute a passive DI box run in reverse if you want to do it on the cheap, but the proper name-brand box is supposed to be much better.

The box is meant both to attenuate the line-level signal down closer to what the amp "expects" as well as to better match the lo-Z output of the recorder to the hi-Z input of the amp.

It's my contention that this is a bunch of hooey. Coming both from my limited understanding of the physics of the situation and my real-world experience of running lo-Z line-level signals through various pedals and amplifiers, I don't really see the issue excpet in certain special situations.

As I understand it, there is no real issue running a lo-Z output to a hi-Z input. Going the other way can cause loss of level and/or tone, sure, but this should be fine. Otherwise, our beloved stompboxes would have to be designed quite a bit differently.

The next biggest problem is the level mismatch. Just about every line-level source I can think of is going to include some form of output volume control. Turn that down till it stops distorting. Or, if you're like me, turn it up till it starts distorting, then turn it some more. There isn't enough voltage here to hurt an "instrument" input, it just might not sound too good.

This leaves us with the problem of possible ground loops between recorder and amplifier. This is a real concern, and can be eliminated by isolating the circuits via transformer. There are other ways, most of which aren't as likely to color the sound.

Oh, it is true that you'll want to be careful to properly unbalance the recorder output. How you do this depends on how the signal gets balanced to begin with, but doesn't usually need a transformer or any other fancy circuitry.

So, anybody who understands the physics better than I, or has more experience with this have any opinions?















(edited by sumgai to "(insert little R in a circle thing here)" )

[quarry]

Couldn't you simply use a "plug-in", like GuitarRig3 to do the "re-amp"ing?

I usually record my guitar with the "sound" I like right from the start, but sometimes I record direct, with no effects (or amp sims) and then apply these later, via plug-ins.

[sumgai]

ash,

The rule of thumb (sans all the ejumacation):


When dealing primarily with voltages, and currents are negligible - Lo into Hi impedance is not only OK, but desirable. Hi into Lo is asking for distortion and other problems, although they probably won't be destructive of any equipment.

When dealing primarily with currents, and voltages are negligible - small mismatches in either direction can be acceptable for short periods of time, but they are quite frowned upon. Destruction of equipment is almost assured, given either a bad mismatch, or enough time.

Your theories are correct, and Hooey is definitely the name of the game.

That is all (for now).

HTH




sumgai

[cynical1]

Re-amping...man, you live long enough you hear it all...

Back in the day (read as "analog" days) when we didn't have a drummer for demos we used to use a Roland drum machine to lay down the drum track on tape. Then we'd strip everything out of the bathroom, put a bass amp in the tub, stacked on a few books, facing up.

Then we'd run the drum track back from the Tascam into the amp. We'd put mikes in the room and outside, using the bathroom door as a damper.

The echo in the bathroom lent some pretty nice effect to an otherwise sterile drum track.

We just called it "living without a drummer"...

Guess nothing is new under the sun...

Happy Trails

Cynical1

[ashcatlt]

Quarry - If you've spent $$$$$$ on mics and preamps, you want to actually use them every once in a while. There are a number of people on this very board here that would, I'm sure, argue loudly that that a real tube amp is the only way to go. For my part, I don't like the ITB amp sims that I have enough to use them for crucial guitar tracks. I'd much rather "re-amp" through my V-amps. If I had access to the same models that those have in my DAW, I'd use them in a heartbeat.

Sumgai - I started thinking about you after I posted this. You run line level signals out of your various Roland boxes into tube amps all the time. Then again, haven't you got the RF thing in between? Is that a line-level signal?

Cynical1 - I've always called it "doin' watcha gotta do".

[ashcatlt]

Okay, so what about the argument that the amp "expects" to see an input with the characteristics of a typical guitar?

Will it somehow perform differently without the relatively high input Z, inductance, and capacitance of the pickups. Obviously, it will tend to overdrive more when hit with a line-level voltage (unless attenuated), but what about the rest of the stuff?

[sumgai]

ash,

.........
sumgai - I started thinking about you after I posted this.

Awww, now I'm blushing.


I've personally find no discernible (audible) difference in the tonality of inputting any Roland/Boss or Digitech unit straight into a Fender Amp. In nearly all cases, the level is about the same, or perhaps a touch hotter than the standard pickups by themselves. With my synth, I can't overdrive the amp's input, even at max output, but with the modeler, I do notice a slight shrillness at full output.

Bear in mind that's with a guitar amp, and only one manufacturer at that, Fender. I do also have a pair of Fender Bassmans (ouch, that hurts ), and neither of them are bothered by the full output of the modeler, still crystal clear, to my ears. And of course, the same can be said for my "real" system, a Behringer 1202 Xenix mixer, but of course there, I have input pads, so input sensitivity is not the same as a guitar amp.

Now, to your real question: are line levels so much greater than a guitar's signal that they become an impediment to one's tone? No, I don't think so, but the question does have to devolve to the sophisication of the input circuitry of the particular amp (or mixer.....). I've never done any kind of testing, formal or informal, but I have seen such on the interwebs, and for the most part, the Tone Nazis are supported by chartable evidence that anything other than a straight guitar into a guitar amp has an effect on the tone. Whether or not it's a bad effect, that remains to be seen (or heard).

Of course, my standard response to such drivel is - what are your customers (the audience) listening to, a bunch of fancy-schmancy electronic testing gizmos, or you, playing whatever equipment sounds good to you? I think that settles the question, at least for me.

The final answer is, unless there are grave concerns for safety, or for the longevity of one's equipment, then screw what the book says, do what newey tells you - Boogie 'til you puke!! ;D ;D ;D ;D

HTH





sumgai

[newey]

do what newey tells you - Boogie 'til you puke!! ;D ;D ;D ;D

Well, that's not exactly what I said, but I'll accept the sentiment.

Actually, IIRC, "Boogie Til You Puke" was a song by Root Boy Slim and the Sex Change Band- but I didn't google that, so I may be misremembering my '80s post-punk one hit wonder bands here.