Amplifiers are a staple in any musician’s toolbox. Whether it’s for your guitar, bass, or keyboard, your amp is the key that makes your instrument heard. But different amps have different functions. So, can you plug a microphone into a guitar amplifier?
You can plug a microphone into a guitar amplifier, and it should work, but you’ll need an XLR to TRS adapter to connect the two. You may also need a phantom power supply if the mic requires one. Try to keep the feedback low and the volume down to avoid damaging the amp.
A guitar amplifier is designed to work with guitars specifically, so they may not be the perfect option for your needs. But if you’re in a bind and need to make it work, it can be done with the right tools and a bit of care. Just be sure to do your research first. Let’s take a closer look at how guitar amps and microphones work and how to use them together.
Can You Plug a Microphone Directly Into a Guitar Amp?
You can plug a microphone into a guitar amp, but you’ll need a few accessories to make it work right, including an XLR to TRS adapter and potentially a phantom power supply.
Microphones use a balanced XLR connector. A guitar amp would have a 1/4″ unbalanced TS or TRS input. The hardware side of the equation is not the only part of the story, though. It can be easily solved by using an XLR female to 1/4″ male cable adapter (on Amazon), and you’ll get the connection that you need.
Considering the balanced and unbalanced situation is more important because it indicates that a guitar amp is not designed for a microphone. Even with the right adapters, you’ll want to be aware of potential problems like noise and impedance mismatches.
It’s worth mentioning that you can find a few microphones with TRS connectors, but they’re not industry standard and are often low quality.
Explaining Phantom Power
The next thing to consider is that certain microphones need phantom power to work — a voltage sent down the XLR cable to power active electronics in the microphone.
Unfortunately, guitar amps don’t supply any kind of power, so you’ll have to find an alternative way to power your microphone. This is usually done with a separate phantom power supply (on Amazon) connected between your microphone and guitar amp.
Some small, battery-powered microphones don’t need phantom power and will work just fine with a guitar amplifier. But if you’re using a professional quality microphone, you’ll likely need some phantom power supply to make it work.
Even if you solve the hardware challenges, the sound quality might not be what you’re looking for. A guitar amplifier is designed to amplify line-level signals, which is what an electric guitar or bass emits. A microphone, on the other hand, emits a mic-level signal.
This means that a guitar amp will amplify the noise along with the signal, which can create a lot of feedback and distortion. And even if you manage to avoid feedback, the sound quality will be poor because the mic-level signal is too weak for a guitar amp, which is obviously not ideal.
Should You Plug a Microphone Into a Guitar Amp?
It’s not necessarily a bad idea to plug a microphone into a guitar amplifier. If you’re in a pinch and need to make your voice heard, it’ll do the job. But there are some significant drawbacks that you should be aware of.
A guitar amp is designed to amplify the signal of an electric guitar, which is very different from the signal of a microphone. Guitar or other instrument sounds are less percussive or transient than vocals. The frequency width is also limited; most guitars don’t output more than 6 kHz, delivered with a smooth roll-off.
On the other hand, vocals are diverse. A single note may have various overtones and harmonics, each with its own nuances and subtleties. The frequency width is also much greater than a guitar’s, while the overall bass is low. All of these factors make vocals a lot more challenging to amplify than guitars.
So when you plug a mic into a guitar amp, the output may not be as clean or articulate as it would be if you were using a dedicated vocal amp.
Sometimes, guitar amps are required to add a bit of grit or distortion to the guitar sound. In vocal application, this is generally undesirable. Nonetheless, a few musicians have used this to their advantage.
So, it’s not a perfect situation — but not that bad either. It really depends on what you’re going for and how you’re using the amp. If you’re looking for a clean, articulate sound, then you’re better off using a dedicated vocal amp. But if you don’t mind a bit of imperfection, then go ahead and use your guitar amp.
Is It Bad to Plug a Mic Into a Guitar Amp?
If you’re worried about damaging your guitar amplifier in any way, then don’t be. Guitar amplifiers are perfectly capable of handling loud sounds without any problems.
The only thing you need to be careful of is the intense feedback. It happens if the sound from the amplifier is picked up by the microphone and sent back through the system.
You can avoid this by increasing the distance between the microphone and the amplifier. Also, avoid beatboxing and cranking up the volume too high.
Another important precaution is to never plug or unplug any cables while your guitar amplifier is turned on. Rarely, this can cause a power surge that could potentially damage the amplifier.
So, always make sure to turn off your amp before doing any cable swapping.
To sum it up, as long as you’re using common sense, there’s really no danger in using your guitar amp with a microphone.
How Do You Plug a Mic Into a Guitar Amp Properly?
There are two phases of plugging a microphone into a guitar amplifier — the hardware setup and the tuning.
Hardware Setup
The first thing to understand is the type of microphone you’re using: does it require a power source, what kind of connection does it have, and which input do you need for your guitar amplifier?
If you’re using an XLR microphone, you’ll need an XLR-to-TS/TRS cable or an XLR-to-TS/TRS adapter (on Amazon). Connect the microphone male XLR to the female XLR of the adapter, and then connect the other TRS end of the adapter to your guitar amplifier.
A direct adapter is more suitable because a long unbalanced cable can deteriorate the sound quality. Make sure your amp is turned off while you’re connecting the cables.
Dynamic microphones don’t need any power supply and can be directly connected to the guitar. On the other hand, if you’re using a condenser microphone, you’ll need to connect it to a power source, either a direct DC power supply or a “phantom power” source.
In that case, the microphone’s XLR male end will connect to the power supply input port, and the adapter’s XLR female end will attach to the power supply output port.
Wireless or battery-powered microphones are more convenient. With those, you need to connect the receiver to the guitar amplifier.
Tuning
The second phase is adjusting your guitar amplifier’s input level and EQ so that the microphone’s sound is amplified without distortion.
Guitar amps are prone to feedback distortion, which increases when your instrument is close to the amp. So the first thing you need to do is move your amp away from the microphone — a distance of 6-8 feet should be good enough. It’s best to get someone to hold the microphone while you’re adjusting the levels.
Start with the volume controls. Bring down the volume of your amplifier to zero and then slowly turn up the input level until you hear a clear sound. Then move on to the EQ controls. Start with the mids and then work your way up or down depending on what you’re trying to achieve.
Using a condenser microphone, you can also experiment with the polarity switch. And that’s it! You’re now ready to rock out with your newly amplified sound.
What Type of Amplifiers Are Suitable for a Microphone?
When choosing an amplifier for your microphone, you need to consider the type of microphone and the purpose of the amplifier.
For live performance, for example, you will need a powerful PA system that can amplify the sound of your voice to reach the entire audience. It’s a system because it includes multiple parts — the amplifier, speakers, and mixer — that all work together.
The wattage of the amplifier (measured in watts per channel) and the size of the speaker(s) determine how loud the system can get. You might need more than one amplifier if your PA system is very large.
In contrast, a recording studio might use a much smaller, less powerful amplifier but with higher-quality components to get a cleaner sound. These types of amplifiers are also called “audio interfaces” because they often have digital inputs and directly connect to a computer.
You can find a wide range of audio interfaces to match any budget.
Bottom Line
Guitar amplifiers can be used with microphones, but it’s important to understand how to do it properly to avoid any accidents or damage. Different microphones require different types of connectors and adapters, so be sure to choose the right ones.
Once everything is connected, you’ll need to experiment with the input level and EQ settings to get the best sound possible.
Guitar amplifiers may not be the perfect match for microphones, but with a little creativity, you can make them work for your home practice or small gigs.