Speakers and microphones are like the two sides of the same coin — they have very similar technology. Also, I’m sure you’ve probably seen or heard about people using speakers as microphones. That’s a very common practice used in music studios to capture audio. But what about microphones? Can microphones be used as speakers?
In short, yes. A microphone can work as a speaker when you plug it in an audio output jack. Microphones have a diaphragm that vibrates to produce sound when it receives an audio signal. Although it will make a sound, it won’t be loud enough. You also run a risk of damaging the microphones.
Before we dive deep into this subject, let’s briefly talk about speakers and microphones, their differences, and most importantly, their similarities. And then, we’ll follow that up with how to use microphones as speakers.
Later in the article, I’ll give you some real-life applications on how microphones are used as speakers, and then I’ll give you my opinion on whether you should ever consider using a mic as a speaker. Let’s get into it.
Microphones vs. Speakers
Microphones have an important component known as the diaphragm. It’s a very sensitive part of the microphone and extremely lightweight. Due to its properties, it vibrates when a sound wave hits it.
The other components inside the microphone, such as the voice coil and magnets, help convert the diaphragm’s vibration into an audio signal in the form of an electric current.
On the other hand, speakers receive an audio signal from an amplifier in the form of an electric current. The signal (or electric current) gets sent to the speaker’s voice coil. The coil immediately turns into an electromagnet once the electric current passes through it.
This will cause the voice coil to move back and forth, repelling and attracting the speakers’ permanent magnets. The back and forth movement of the voice coil will cause the speaker diaphragm to produce sound.
In essence, microphones are designed to pick up sound waves with the microphone diaphragm and convert that into audio signals. Speakers, on the other hand, receive audio signals and convert them into sound waves by vibrating the speaker’s diaphragm.
So, by definition, you can already tell that a microphone and a speaker does the exact opposite thing.
If you paid a little attention while reading this, you’d have probably noticed one thing — both a microphone and a speaker has a diaphragm. However, the difference between the diaphragm of a speaker and a microphone is their size.
By design, microphones have a much smaller diaphragm that is also lightweight. They are made to be small and lightweight so that they can vibrate when they get hit by a weak sound source. This is why I mentioned earlier this a very sensitive part of a microphone.
The diaphragm of a speaker, on the other hand, is much larger. That’s because it is not designed to capture sound but rather to produce sound. If all of this sounds confusing, stick around, you’ll understand why shortly.
How to Use Microphones as Speakers
As we have already discussed in the previous section, how speakers work is the reverse of how microphones work. So, to make microphones work as speakers, you need to operate them in reverse. What do I mean by this?
Microphones are usually plugged into a mic input on a preamp, mixer, or audio interface with an audio cable. The mic will then send an audio signal in the form of an electrical current to these devices. Essentially, microphones are known to be input devices.
To operate a microphone in reverse means, you have to use it as an output device, just like a speaker.
To use microphones as speakers, simply plug it in a line output. You should be able to hear whatever audio you are playing through the microphone.
You don’t have to modify the microphone in any way. Once it is plugged into an audio output with audio playing, you should hear the audio playback through the mic.
Real-Life Applications – Intercoms/Walkie Talkie
If you don’t know what an intercom is, these are the small radio devices used for communication purposes. The handheld versions of intercoms are walkie-talkies, commonly used in hospitals, engineering fields, and more to communicate. Nowadays, intercoms are used in homes and offices all around the world for easy and cheap communication.
In the early days, the first intercoms and walkie talkies only had speakers which doubled as a microphone (or microphones which doubled as a speaker – either way). To send audio, you had to press a button, which will convert the speaker into a microphone. Once you release the button, it becomes a speaker, ready to receive audio.
Downsides of Using a Microphone as a Speaker
Although microphones can work as speakers, there are many reasons why you should probably not use them as one. And I’ll try to explain why.
Firstly, as I mentioned earlier, Speakers have a much bigger diaphragm compared to the tiny diaphragms on microphones, and it makes complete sense why.
Speaker diaphragms are designed to move air in order to produce sound waves. The more air a speaker diaphragms can move, the louder the sound it can produce. That is the primary difference between big and small speakers — the size of the diaphragms.
On the other hand, microphones have a much smaller diaphragm because they are not designed to produce sound but to capture sound. For this reason, mic diaphragms can’t move enough air to produce a loud enough sound.
So, yes, you may hear the microphone make a sound when you plug it in kan audio output jack. However, it may be loud enough if audible at all. Probably, you may have to place the microphone close to your ears even to hear a sound.
Also, even if the microphone works as a speaker, the sound quality will be poor. Mic diaphragms are too tiny to produce the mids and low frequencies of audio. You’ll only be able to hear the higher frequencies of whatever audio you are playing through them, which isn’t a correct representation of what you are listening to.
Lastly, you risk damaging a microphone by using it as speakers? Why? Let me explain.
The audio signal received by speakers is a much stronger amplified signal. This means the electrical current received by speakers is much higher. Running such a high current audio signal through a microphone can potentially damage it. That’s because its components are not designed to handle the high electric current.
Should You Use a Microphone as a Speaker?
I wouldn’t recommend using a microphone as a speaker. That’s because microphones won’t give you high-quality sounding audio, so chances are you won’t enjoy listening to audio playing through a mic.
You should rather get decent sounding speakers or even headphones to listen to your audios instead of using a mic.
Another reason why you probably shouldn’t use a mic as a speaker is you can easily damage it. If you don’t really care about your mic’s longevity, then great, you can definitely do that. But if you don’t want to risk damaging your microphone, you definitely shouldn’t use it as a speaker.
What you can do to prevent your mic from damaging is first to turn down the volume on the mixer or amplifier before you plug in the mic in an audio output jack. Once you plug it in, you gradually turn up the volume until you hear an audible sound from the mic. That may eliminate high audio signals damaging the mic. But personally, I wouldn’t risk it.
In summary, microphones can be used as speakers. All you have to do is connect them to an audio output such as headphone outputs or line outputs. Keep in mind, however, that they won’t play loud enough because microphones have a tiny diaphragm. You also risk damaging your microphone using it as a speaker.