Amp in a box: What is it?
The answer to this question isn’t something that can satisfy everyone using a device labeled as an amp in a box. One thing that every musician could agree on is that it has a stompbox format. Rack devices fall into an “amp in something” format, so we won’t discuss them.
OK, it’s a pedal. But what does it do besides looking nice on a pedalboard?
An amp in a box replicates the sound and behaviour of a specific amp. Many can faithfully replicate multiple classic guitar or bass amplifiers.
It can be analog or digital. Some have analog and digital functionality combined.
Some amp-in-a-box devices are digital (DSP) and can recall the sounds of endless amps, cabs, microphones, their placement, and STOP! Are they amps in a box? Technically, yes, but I don’t like to use this term for them because they do many other things.
Some pedals are real amplifiers in a stompbox format, but their main purpose is to be a power amp, rather than creating an amp’s preamp section sound. These pedals are meant to be used after a preamp pedal, last in the chain.
Who is an amp in a box for?
1. Musicians who use pedals for effects and don’t need a multi effects and amp modeller device because they have their tone, but want to downsize their favorite amp. They would be wasting their money by buying a Fractal, Helix, or Neural DSP all-in-one unit, because they already have the effects they need and don’t need digital replicas of dozens of amps, only one or two.
2. Guitarists who want to have the freedom to play different amps during a single gig. Carrying one monster amp is hard enough; what about two or three?
3. Those who don’t have money to buy the “real thing”.
4. Guitarists and bassists who have health problems, mostly back problems.
Amp in a box: Main functions
An amp in a box can do all the stuff mentioned in the intro. The microphone you use to mic an amp and its placement contribute to the overall sound too, but they are not a part of the actual amp. By amp, we are talking about the main components of a guitar or bass amp.
Every amp, whether a combo or not, consists of these parts:
- Preamp
- Power amp
- Cabinet (speaker, cabinet, and material characteristics)
The preamp is where the sound is shaped. This is where it gets its main characteristics it is known for. This very weak signal then gets stronger with the power amp so that the speaker or speakers can be powered.
Most amp-in-a-box pedals have features that let you choose various settings:
- Preamp section: gain, EQ, clean or drive channel, reverb,…
- Power amp: Level or master
- Speaker type
- Amp model
- Mic type and placement
How to use an amp in a box?
An amp in a box pedal can be used between a guitar and a physical amp. This is for those who don’t want to ditch their favorite amp but want to have another amp sound as well. When using the pedal this way, the physical amp should be tweaked to the cleanest sound you can get, so the amp sim pedal’s sound can be noticeable. Otherwise, you’re mixing the sounds of two amps.
To get the true sound of the pedal that emulates an amp, it should be used plugged directly into a PA or an FRFR speaker. Amps that have send and return inputs can also be used as a power amp. By plugging a pedal into the return input, the preamp section gets bypassed and only the power amp is used. This prevents any coloration of the amp-in-a-box pedal’s sound.
Amp-in-a-box pedals also act as DI boxes. Since we are not using any microphones to mic an amp, it is no wonder that some amp simulator pedals have the option to choose different mic placement settings.
Other uses for an amp in a box
Recording
When it comes to recording guitars, the amp in a box concept is widely used. The controlled conditions of a studio don’t need a real amp to get an almost perfect replicated sound from a preamp guitar pedal. Side-by-side tests show that it is almost impossible to distinguish a recorded amp pedal from the recorded real amp.
Silent practice
Big valve amps sound their best when cranked up a bit, or all the way. This is a nightmare for our family and neighbours. No matter how low the volume of a valve amp is, you will never get that sound. Pedals that simulate an amp sound the same at all levels. Put on a pair of headphones and you’re playing in the stadium.
Benefits of using an amp in a box pedal
1. Portability
When playing frequent gigs, where travelling hundreds of miles is a normal thing, you know that a Fender twin isn’t the easiest thing to lug around. Especially if you are a musician and a roadie, all in one. With an amp in a box, you save space, weight, and what’s most important, your energy.
2. Flexibility
If you want to go the amp in a box route, you have the privilege of using more than one amp sound. Changing pedals that emulate guitar or bass amps is, well, easy.
3. Consistent sound
The sound of a real-world amp depends on many factors, like mic placement and venue acoustics. Tube amplifiers also change their sound with oscillations of the current we use in certain venues.
I used to have huge changes in sound when playing in some restaurants. During soundcheck and the first set, everything sounded great, but when the fried food started getting cooked, my valve amp would start losing power and changing character. A solid-state amp or amp in a box solves this problem.
4. Ampless rigs
Most amp-in-a-box pedals can be used in front of a regular amp. But pedals with a cab sim and DI output can be used instead of an amp. Playing a guitar or bass without a physical amp is referred to as an ampless rig. It’s easy to imagine what the benefits of an ampless rig are.
5. Spare amp
Our favorite amp can stop working during a gig. We need to fly to a gig. These situations are where an amp in a pedal format comes in handy.
Examples of Amp in a box pedals
1. Amt F1
This pedal emulates the sound of a Fender Twin. It is one of the cleanest amp simulator pedals on the market with a ton of headroom.
2. One Control Blue 360 AIAB
The beloved Acoustic 360 bass am in a box. It even has “AIAB” (amp in a box) in the name. All you bass players looking for the sound of John Paul Jones or Jaco Pastorius are in for a treat with this small pedal.
3. Tech 21 SansAmp TRI-A.C.
Tech 21, the legendary analog guitar and bass pedal manufacturer from NYC, has been making pedals since 1989. They know how to make pedals sound like a real valve amp, how about three of them, in one pedal? The TRI-A.C. does exactly that.
4. HX Stomp
The HX Stomp is not only an amp sim pedal, it is many things. I included it in this list because it is a perfect example of a multi-effects, amp modeler, cab sim, and IR load box that can serve as an amp in a box, many amps.
Final thoughts
The amp in a box pedal is not your ordinary effects pedal. It’s a pedal that replicates the sound of an amp. It can be used in front of an existing amp or can completely eliminate the need for a physical amp, which we then call an ampless rig.
You can have several amp-in-a-box pedals for gigs, or have more than one amp simulation on one pedal. You still get to use the amp’s settings: gain, EQ, level, but all without the size and weight of the real thing.
Like all things in life, you need to weigh what’s best for your needs. Do you absolutely need to use a 30-40 lb valve amp, or can you live with a small pedal that sounds very close to the real thing?
