Amp questions. What is re-amping?

[hillerheilman]

Hey forum, I need some more assistance.

I’ve asked reddit about this but I got answers that made things somewhat more confusing for me.
As I said in my other thread, my current guitar setup is all on my iPad via bias amp/fx. I’d like to move away from that and get an actual amp for jamming and home recording.
However, I’d like to be able to still use the effects pedals on bias fx (no amp sim, just the effects coming through the actual amp) in lieu of an actual pedal board to make things more portable.
So, am I wrong in thinking that I could just plug the guitar into the amp normally and then put the interface into the effects loop of the amp to achieve that? Then if I wanted to record I could just mic the cab.

When I asked on Reddit I got a response about something called re-amping. When I googled it, I wasn’t sure it was something I needed to do. My understanding of it was it just creates a clean recording of your guitar which you then apply effects to after the fact.
What I want is to be able to play just as you normally would, effectively using my iPad as a virtual pedal board.

Can anybody explain what this is and if it’s actually something I need to do?

[marqueemoon]

I would look into the Orange OMEC Teleport. I’m sure there are similar products by others too.

[MazzyJaster]

Reamping is when you send a dry DI guitar signal from a recording device to an amp, and then record it. The main issue is converting the line level signal into Hi-Z before you hit the amp. I use one of these for the job .. http://orchid-electronics.co.uk/Amp_Interface.htm

However, since you are using an iPad and you want to play live, is there a line-level output signal coming out of the iPad? Alternatively, you could try going into the FX loop if you use the Bias amps which should be at line-level, but it all depends on your iPad signal.

[MazzyJaster]

I found this video, but since you only want to use the FX from the bias you will need to go into the front of the amp, so you will need some kind of audio interface. It may just be easier to get a used digital FX unit?

https://www.youtube.com/watch?v=WwVDOGpzDZQ

I do this kind of thing a lot, but I am using a laptop with an audio interface plus a Hi-Z converter. I'm not really familiar with the iPad, so you will need to figure that part out.

[øøøøøøø]

I’ve asked reddit about this but I got answers that made things somewhat more confusing for me.

WARNING: LONG POST AHEAD

What you're trying to do--while possible--isn't the MOST straightforward thing (if you want to do it correctly), which is why it's a little bit confusing. Let's try to break it down in as non-confusing a way possible!

As end users, we tend to be used to things "just working." We don't usually need to know the physics behind what's going on, we just know we plug this into that and it works. But less-common scenarios like this are sometimes a little bit less straightforward, and require a little bit more understanding of exactly what's going on.

Our obstacle in this case is that we're dealing with two different kinds of signal--low impedance balanced versus high impedance unbalanced. Don't let those terms make your mind glaze over--we'll get to it.

[tl;dr: skip this part if you don't really need to know how it works, and just want the solution]

Impedance is a fuzzy concept to get your mind all the way around, but you don't have to have a physicist's understanding.

For our purposes (though a highly-imperfect analogy), we can think of it a little bit like gears on a bicycle. With a bike, we're interested in two things: torque (the force that turns the wheel) and top speed. With audio signal, we're also interested in two things: voltage and current. Different impedances, like different gears, prioritize one over the other.

High impedance devices tend to be lower-current and simple. They can output a signal that's strong enough, but that signal is very fragile (susceptible to noise and degradation over cable distances, interaction with the cable capacitance to change frequency response, etc). Low impedance devices tend to be a bit more complex and expensive, and due to their higher-current design, the signal is much more durable.

Some types of equipment (guitars, many keyboards, your home stereo, consumer audio-visual equipment) are designed for the higher-voltage, lower-current "high impedance" type of signal. Other types of equipment (recording consoles, telephone transmission lines, microphones, most pro audio) are designed to work at "low impedance."

Balancing is a means to reduce noise and interference. In principle, it's a little bit like a humbucker pickup in that it uses "common-mode rejection"

Instead of using one wire with one polarity, we use two wires of opposite polarity. When we later combine the two to make one, we have to flip the second wire's polarity--and in the process, any noise that was simultaneously introduced into both wires gets canceled out to zero. The disadvantage is added complexity and expense, so you generally see this in pro audio applications, and not in consumer audio or musical instruments.

[start reading again here if you sorta want to know why we need to do what we need to do]

Your interface is probably has both low-impedance and high-impedance inputs, but only low-impedance outputs. Your guitar amp's effect loop most likely has high impedance input and output.

Your interface has balanced outputs and inputs... and possibly an unbalanced input as well (if it has a "DI" input that you plug your guitar or keyboard straight into).

We need to make these two worlds collide, and to allow both pieces of equipment to work their best, we will need a third piece of equipment. This is where the "reamp box" comes in.

A reamp box is the opposite of a direct box.

A direct box is something that allows you to plug something like a guitar or bass directly into a mic preamp: it converts high-impedance unbalanced into low-impedance balanced.

A reamp box does the opposite--it converts low-impedance balanced into high-impedance unbalanced.

It gets its name because of its intended function--if someone records a guitar or bass with a DI box or a microphone on an amp, it's captured and recorded into a system that's typically low-impedance and balanced. If we want to run that already-recorded signal out into a guitar amp (which is high impedance and unbalanced), we'll need to convert that signal again (like shifting gears on a bike).

In your case, we need the low-impedance balanced interface to "talk to" the high-impedance, unbalanced guitar amp.

[skip here if you just want to cheat and copy the answer]

So here's a way to accomplish what you want:

• Guitar into the front of your amp.
• "Effects loop send" into the DI input (1/4" in, or guitar in) of your interface.
• XLR output of your interface into Radial Engineering Reamp (or competitive/similar product).
• Output of the Reamp into "effects loop return."
• Adjust levels to something that makes sense (requires more care than you're used to... you want to be careful not to overdrive your effects loop buffer amp or interface input/line amp).

If your interface doesn't have a DI in/guitar in, you'll instead want something like a Pigtronix Keymaster, which has more flexibility in what kinds of signals it can send and receive.

Finally, the answer to the question I know at least ONE person has:

"what if I just pretend I'm dumb and don't know any of this, and just get an XLR to quarter inch adapter, and plug it all in?"

The answer is that things won't work as well as they could. I haven't tried such a thing in this specific instance, but when impedances are wrong, all sorts of things can happen... level can be weird, frequency response can get weird, and generally stuff just doesn't work like it's supposed to.

I know that was long and probably just as confusing as what you saw on Reddit, but there's no way around it--audio is confusing sometimes, especially when you're trying to do "not-normal" things.

Cheers

[hillerheilman]

I’ve asked reddit about this but I got answers that made things somewhat more confusing for me.

WARNING: LONG POST AHEAD

What you're trying to do--while possible--isn't the MOST straightforward thing (if you want to do it correctly), which is why it's a little bit confusing. Let's try to break it down in as non-confusing a way possible!

As end users, we tend to be used to things "just working." We don't usually need to know the physics behind what's going on, we just know we plug this into that and it works. But less-common scenarios like this are sometimes a little bit less straightforward, and require a little bit more understanding of exactly what's going on.

Our obstacle in this case is that we're dealing with two different kinds of signal--low impedance balanced versus high impedance unbalanced. Don't let those terms make your mind glaze over--we'll get to it.

[tl;dr: skip this part if you don't really need to know how it works, and just want the solution]

Impedance is a fuzzy concept to get your mind all the way around, but you don't have to have a physicist's understanding.

For our purposes (though a highly-imperfect analogy), we can think of it a little bit like gears on a bicycle. With a bike, we're interested in two things: torque (the force that turns the wheel) and top speed. With audio signal, we're also interested in two things: voltage and current. Different impedances, like different gears, prioritize one over the other.

High impedance devices tend to be lower-current and simple. They can output a signal that's strong enough, but that signal is very fragile (susceptible to noise and degradation over cable distances, interaction with the cable capacitance to change frequency response, etc). Low impedance devices tend to be a bit more complex and expensive, and due to their higher-current design, the signal is much more durable.

Some types of equipment (guitars, many keyboards, your home stereo, consumer audio-visual equipment) are designed for the higher-voltage, lower-current "high impedance" type of signal. Other types of equipment (recording consoles, telephone transmission lines, microphones, most pro audio) are designed to work at "low impedance."

Balancing is a means to reduce noise and interference. In principle, it's a little bit like a humbucker pickup in that it uses "common-mode rejection"

Instead of using one wire with one polarity, we use two wires of opposite polarity. When we later combine the two to make one, we have to flip the second wire's polarity--and in the process, any noise that was simultaneously introduced into both wires gets canceled out to zero. The disadvantage is added complexity and expense, so you generally see this in pro audio applications, and not in consumer audio or musical instruments.

[start reading again here if you sorta want to know why we need to do what we need to do]

Your interface is probably has both low-impedance and high-impedance inputs, but only low-impedance outputs. Your guitar amp's effect loop most likely has high impedance input and output.

Your interface has balanced outputs and inputs... and possibly an unbalanced input as well (if it has a "DI" input that you plug your guitar or keyboard straight into).

We need to make these two worlds collide, and to allow both pieces of equipment to work their best, we will need a third piece of equipment. This is where the "reamp box" comes in.

A reamp box is the opposite of a direct box.

A direct box is something that allows you to plug something like a guitar or bass directly into a mic preamp: it converts high-impedance unbalanced into low-impedance balanced.

A reamp box does the opposite--it converts low-impedance balanced into high-impedance unbalanced.

It gets its name because of its intended function--if someone records a guitar or bass with a DI box or a microphone on an amp, it's captured and recorded into a system that's typically low-impedance and balanced. If we want to run that already-recorded signal out into a guitar amp (which is high impedance and unbalanced), we'll need to convert that signal again (like shifting gears on a bike).

In your case, we need the low-impedance balanced interface to "talk to" the high-impedance, unbalanced guitar amp.

[skip here if you just want to cheat and copy the answer]

So here's a way to accomplish what you want:

• Guitar into the front of your amp.
• "Effects loop send" into the DI input (1/4" in, or guitar in) of your interface.
• XLR output of your interface into Radial Engineering Reamp (or competitive/similar product).
• Output of the Reamp into "effects loop return."
• Adjust levels to something that makes sense (requires more care than you're used to... you want to be careful not to overdrive your effects loop buffer amp or interface input/line amp).

If your interface doesn't have a DI in/guitar in, you'll instead want something like a Pigtronix Keymaster, which has more flexibility in what kinds of signals it can send and receive.

Finally, the answer to the question I know at least ONE person has:

"what if I just pretend I'm dumb and don't know any of this, and just get an XLR to quarter inch adapter, and plug it all in?"

The answer is that things won't work as well as they could. I haven't tried such a thing in this specific instance, but when impedances are wrong, all sorts of things can happen... level can be weird, frequency response can get weird, and generally stuff just doesn't work like it's supposed to.

I know that was long and probably just as confusing as what you saw on Reddit, but there's no way around it--audio is confusing sometimes, especially when you're trying to do "not-normal" things.

Cheers

Really helpful answer. Way less confused now. Thanks very much. Slightly different from how I was told on Reddit. On Reddit the chain went:
Guitar, interface/iPad, interface out to reamp unit. Then reamp unit to amp input.

[marqueemoon]

Here is a quick OMEC Teleport overview.

https://youtu.be/ZaBB-Qh0yDo?t=158

[øøøøøøø]

Really helpful answer. Way less confused now. Thanks very much. Slightly different from how I was told on Reddit. On Reddit the chain went:
Guitar, interface/iPad, interface out to reamp unit. Then reamp unit to amp input.

No problem!

The chain you describe (from Reddit) would also work, provided you didn't want to use your amp's effects loop.

This depends somewhat on what kind of effects you want to use and how you want them to work. Overdrive, boost, compression, distortion, fuzz, envelope effects, etc. might work well into the front of the amp. Tremolos, delays, reverbs, other time-based effects might work better in the loop.

If you're using some of all, it might work better to go into the front as they said on Reddit.

Of course you could always try both ways.