Can You Use An Acoustic Amp With An Electric Guitar?

If you have an electric guitar, then you know it isn’t very useful without an amplifier. That’s because electric guitars are built to produce sound through their pickups, as opposed to just with the vibration of the body.

But what if you don’t have an amp designed for an electric guitar? Can you use an acoustic amp with an electric guitar?

You can use an acoustic amplifier with an electric guitar, but it will sound quite different from an electric guitar through a regular amp. The tone will be clean but will also sound somewhat flat, because acoustic amplifiers are more similar to a PA system than a traditional guitar amp.

Let’s look at how traditional guitar amplifiers work, how acoustic amplifiers are different, and why you might or might not like the tone you get from plugging an electric guitar into an acoustic amplifier.

How Is An Acoustic Amp Different From A Regular Guitar Amp?

When amplifiers were first being developed, in the 1920s, they were small PA systems, as opposed to something designed to amplify a particular instrument.

At first the amplifiers would be used with microphones, but starting in the early 1930s, the development of the magnetic pickup meant the vibration of the strings of a guitar could be turned into an electric impulse, which could then move the speaker cone of an amplifier.

The circuit layout of those early amplifiers, including their use of vacuum tubes for both preamplification and power, meant that while the idea was to faithfully reproduce the sound of the strings, the reality was different.

Early amps often had just a single volume control. That meant any tone adjustment had to happen on the guitar, if that was even an option.

Because of the way vacuum tubes work, there is a threshold where they start to produce harmonic distortion. Once you reach that threshold, then the louder the volume gets, the more the sound will distort.

The amplifier’s frequency response also had to do with the difference in sound.

These technical limitations likely ended up helping the guitar, because it created a distinctive sound, one that cut through the sound of other instruments better than an unamplified guitar while not clashing with them.

As solid state amplifiers were developed, they overcame many of the technical limitations when it came to tube distortion. While a lot of players find such distortion pleasant, it isn’t right for every case.

Guitar players who needed a clean sound and the volume to be heard over other instruments turned to solid state. But while those amps allowed players to dial in distortion with a gain knob, their frequency responses were still much the same as older amps.

At the same time, though, solid state PA systems were also becoming more and more ubiquitous. Those used circuits that were designed from the ground up to have very faithful frequency reproduction.

How Does An Acoustic Amplifier Work?

Many acoustic guitar players will use a DI box to send their guitar’s signal to the PA system.

If there’s going to be a sound check, where the performer and the engineer can dial in the correct EQ and volume, that will normally work quite well. In venues without a PA system, or when there isn’t anyone running the sound board, an acoustic amp is often a better option.

That’s because while a DI box is very portable, it leaves most of the shaping of the sound to the PA system. If you want more control, an acoustic amp, which is on stage with you, allows you to make changes on the fly.

And in many ways, the circuits in an acoustic amplifier are similar to those in a modern PA system. The main differences are the way the EQ of the amplifier is voiced and the fact many acoustic amps offer built-in effects.

For the EQ, while the basic frequency response of the amp is similar to a PA system, the tone controls are centered around the frequencies that will do the most to shape the sound of an acoustic guitar.

Some PA systems offer built-in effects, but not all of them do. Nearly all acoustic amplifiers offer a range of built-in effects, though.

Most are equipped with different kinds of digital reverb, as well as other modulation and time effects like delay, echo, vibrato, and chorus. This allows you to dial in the right sound and change it from song to song, if needed, as opposed to needing to rely on a sound engineer to make changes.

This video goes over why players who use acoustic guitars might want an acoustic amp.

Using An Acoustic Amp With An Electric Guitar

What about playing an electric guitar through an acoustic amp, though? What would that sound like?

Depending on what you expect, you might be quite disappointed. Think of the typical electric guitar sound — a lot of midrange, which can stand out in a band where a bassist is handling the low end and other instruments are playing in higher registers.

That’s a lot different from the round, warm sound typical of most acoustic performances. Acoustic guitars are typically more resonant sounding, also.

The difference in typical pickup types between electric and acoustic guitars also contributes to the difference in sound through an acoustic amp.

Some acoustic guitars use a magnetic soundhole pickup, but many others use an under saddle piezo pickup, an internal mic, or some combination of those. Both of those pickups sense the vibration of the guitar body as opposed to the vibration of only the strings.

Because acoustic amps offer a very faithful representation of the sound, a magnetic pickup on an electric might sound quite dull in comparison to the way an acoustic guitar sounds through the same amp.

That doesn’t mean there is no place for using an acoustic amp with an electric guitar, though. Some genres of music and some instrument types can make good use of what an acoustic amp can do.

Jazz, for instance, especially when played on a hollow or semi-hollow body guitar, works quite well through an acoustic amp.

Another potential advantage of using an acoustic amp is that most are dual channel, meaning they can take two input sources at the same time, and support microphones.

That means a singer-songwriter with an acoustic can carry just the one amp, but it can do the same thing for a two- or three-piece jazz combo with a guitarist and a vocalist.

And if you want to play a different genre, you can use an overdrive pedal, a multi-effects pedal or amp modeling pedal to shape the sound of your guitar tone, using the acoustic amp much like an ultra-portable PA system.

Conclusion

Usually, when it comes to choosing amps, it makes the most sense to stick with the basics — electric guitars work great through traditional amps, and acoustic amps are excellent for acoustic guitars.

But there are always going to be some exceptions to that. A major one would be: You need to perform and the only thing available is an acoustic amp.

If you’re not a jazz player, who can really take advantage of the wider frequency response and dynamic range of an acoustic amp, you can use effects to help shape the sound, whether that’s the ones that are built in or from effects pedals.

James Kelly

I’ve been a musician, particularly a guitarist, for more than 25 years. I love writing about guitars, gear, recording, music in general and more.