Can You Plug a Microphone into a Guitar Amp? Explained

The world of audio equipment is fascinating, complex, and sometimes confusing. Whether you’re a musician, a podcaster, or just someone who loves to experiment with sound, there are endless combinations of gear to consider. One question that often comes up among enthusiasts and novices alike is: “Can you plug a microphone into a guitar amp?” While it may seem like a straightforward question, the answer involves a bit of nuance.

This article aims to shed light on this subject, offering insights into what happens when these two distinct pieces of audio equipment combine.

Can You Plug a Microphone into a Guitar Amp?

Yes, you can plug a microphone into a guitar amp, but it’s not always ideal for sound quality or clarity. Guitar amps are designed to amplify the frequencies of a guitar, not the human voice. Consequently, while you might get sound out of the amp, it may not reproduce the vocal frequencies as accurately or as clearly as a dedicated PA system or vocal amp.

Also, plugging a microphone into a guitar amp could lead to feedback issues, especially if the microphone is positioned close to the amp.

Why You Should Not Plug a Microphone into a Guitar Amp

1. Impedance mismatch

Impedance is a measure of how much a device resists or impedes the flow of an AC current, and different audio devices are designed with specific impedance ratings. Microphones typically have a low impedance, while guitar amps are designed to work with the high impedance output of electric guitars.

Plugging a low impedance microphone into a high impedance guitar amp input can result in weak signal strength, leading to poor volume levels and compromised sound quality.

2. Potential Sound Quality Issues

Guitar amplifiers are engineered to reproduce the tonal characteristics of guitars, which means they emphasize certain frequencies that guitars commonly produce. A human voice has a very different frequency range and tonal quality than a guitar.

When a microphone is plugged into a guitar amp, it might not capture the full depth and nuance of the voice. This can lead to a muddied or tinny sound, failing to deliver the clarity and richness you’d expect from a PA system or a vocal amp.

3. Feedback Issues

Guitar amps, especially when turned up to high volumes, are prone to feedback when used with microphones. This is the high-pitched squeal you sometimes hear. The design and positioning of guitar amps make them more susceptible to this, especially if the microphone is placed too close to the amplifier. The feedback can be annoying and potentially damaging to the equipment.

4. Lack of Necessary Features

Guitar amps are generally devoid of features that are essential for vocal clarity and enhancement. For instance, they might not have the EQ controls appropriate for shaping vocal tones or effects that are tailored for voice, like reverb. On the other hand, dedicated vocal amps or PA systems usually come with these features, allowing you to tweak the sound to suit vocals specifically.

5. Potential Damage to the Equipment

Continuously using a guitar amp for purposes it wasn’t designed for might lead to suboptimal performance and potentially reduce the amp’s longevity. Overdriving the amp with signals it’s not designed to handle might cause wear and tear faster than normal usage.

Why You Might Want to Plug a Microphone into a Guitar Amp?

1. Quick Setups for Small or Impromptu Performances

There are moments when precision and sound quality take a backseat to immediacy and convenience. Perhaps you’re at a casual backyard party or an impromptu jam session, and all you have on hand is a guitar amp.

In such scenarios, plugging a microphone into a guitar amp can provide a straightforward solution. It allows for a quick setup without the fuss of arranging a dedicated PA system, making it a practical choice for informal settings where the audience is more forgiving.

2. A Unique Sound or Effect for Artistic Purposes

Artistic expression often thrives on experimentation. Musicians and artists are known to use equipment in unconventional ways to discover unique sound textures and effects.

A guitar amp can color the sound of a voice in a way that a standard vocal amp or PA system won’t. This can be especially appealing for certain genres or experimental music projects where a raw, distorted, or uniquely colored vocal sound is desired.

3. Situations When Dedicated Vocal Gear is Not Available

Sometimes, necessity is the mother of invention. In situations where a musician or speaker finds themselves without access to specialized vocal amplification, a guitar amp might be the only available option.

This could be in remote locations, during travel, or in settings where the primary equipment malfunctioned. In such cases, using a guitar amp for vocals is a practical workaround, ensuring that the show goes on, even if it’s not under ideal conditions.

How Do You Set Up a Mic for a Guitar Amp?

1. Choose the right microphone

Many different types of microphones are available, so it’s important to choose one that will be compatible with your amp and the sound you’re trying to achieve. Some popular choices for miking guitar amps include dynamic microphones, condenser microphones, and ribbon microphones.

2. Connect the microphone to the amp

Most microphones will have an XLR output, which will need to be connected to an XLR input on the amp. If your amp doesn’t have an XLR input, you can use an adapter to convert the XLR output to a 1/4-inch jack.

3. Find the right microphone placement

The best microphone placement will vary depending on the type of microphone you’re using and the sound you’re trying to achieve. However, a good starting point is to place the microphone about 6 inches to 12 inches away from the center of the speaker cone. You can experiment with different placements to find the one that sounds best to you.

4. Adjust the microphone’s gain

The gain control on the microphone will determine how much signal is being sent to the amp. Start with the gain turned down low and then increase it until you get a good signal level. Be careful not to overdrive the microphone, as this can cause distortion.

5. Adjust the amp’s settings

The amp’s settings will also affect the sound of the microphone. Experiment with different settings until you find a sound that you like.


To sum up, you can plug a microphone into a guitar amp, but it’s not always the optimal choice for high-fidelity sound reproduction. While it might work in a pinch or for specific creative effects, using a guitar amp for a microphone has limitations in frequency response, potential feedback issues, and sound quality.

Investing in a PA system or a dedicated vocal amplifier is generally better if you plan on having a dedicated vocal or spoken word setup. Nevertheless, understanding the intricacies involved helps one make informed decisions, offering flexibility and creativity in sound manipulation.