Have you ever wondered if microphones are designed as input or output devices? It’s a fair question if you’re just getting started recording audio or connecting mics to your computer. In this simple guide, we’ll break it down in easy-to-understand terms so you can wrap your head around the input/output concept.
Microphones play a crucial role in many audio applications, from music recording to podcasting to voice calls. But to use them effectively, it’s helpful to know whether they are sending or receiving signals. We’ll answer the question [Is A Microphone Input Or Output] definitively by the end!
What Are Input and Output Devices?
First, let’s define the key terms:
An input device sends information into a computer or recording system. Some examples of audio input devices are microphones, MIDI keyboards, and turntables. These devices convert acoustic, mechanical, or optical inputs into electrical signals that get sent into the system.
An output device receives information from a computer or playback system and converts it into something we can perceive with our senses. Speakers and headphones are common audio output devices. They take electrical signals coming from the system and turn them into sound waves we can hear.
So in summary, inputs send signals in, outputs receive signals out. With that basic concept down, let’s see how mics fit in.
Microphones as Input Devices
Microphones are designed to be input devices for several reasons:
- They convert acoustic energy (sound waves) into analog electrical signals
- The analog signals then get sent to devices like audio interfaces for analog-to-digital conversion
- The digital data gets inputted into a recording system like a computer or smartphone
So in their most basic function, microphones take sound and transform it into signals that get inputted into devices.
Those analog audio signals from the microphone typically need to be converted to digital data before being fully inputted to a digital system like a computer. There are a few ways this analog-to-digital conversion can happen:
- Audio interface (hub style) – A desktop box with microphone inputs and software for recording. The Focusrite Scarlett 2i2 is a popular model.
- Audio interface (adapter style) – A smaller inline device like the Shure X2U which adapts XLR to USB.
- Digital microphone – A mic with a built-in analog-to-digital converter like the Blue Yeti USB mic.
No matter the type, microphones are inherently designed as the start of the signal chain. They output electrical signals and do not receive signals back in. The sound waves hitting the mic capsule are the “input” that gets converted to an electrical output signal.
Standalone Microphone Inputs and Outputs
Looking just at a bare microphone not connected to any gear, we can summarize:
- The microphone outputs analog audio signals (AC voltages)
- Some mics require DC power to operate, but this is not an audio input signal
- Microphones are not designed to receive analog or digital audio signals back in
- The sound waves that hit the microphone capsule are a mechanical input which causes the electrical output
So in their intended function, microphones accept sound waves as input and give audio signals as output. They begin the signal chain rather than receive signals further down the line.
Using Microphones as Speakers
Here’s where it gets interesting. Since microphone and speaker components are quite similar, it is actually possible to reverse the signal flow and use a mic like a speaker!
For dynamic and ribbon mics, connecting an audio source to the mic output will cause the diaphragm to move and create sound waves. With condenser mics, you’d also need to maintain polarization voltage.
Caution is advised not to blow up your prized microphone, but with the right setup it can work. If you’re curious to try this speaker-to-mic hack, check out this guide.
While using a mic to output audio is possible, it’s not the intended design. In most cases it’s best to stick with mics as inputs and speakers as outputs.
To summarize so far:
- The vast majority of microphones are designed as input devices
- However, digital mics with built-in headphone amps act as both input and output devices
- Headphones with integrated microphones are also input/output devices
So under normal conditions, it’s safe to think of mics as inputs that start the audio signal chain. But some multi-functional models blur the lines a bit.
Microphone Selection for Intended Use
When choosing a microphone for a particular purpose like recording vocals or a podcast, consider:
- The mic’s intended design as an input device
- Self-noise – how much noise the mic adds on its own
- Frequency response for the source audio
- Polar pattern to match the environment
The answer to “Are microphones input or output devices?” is primarily input. Microphones are designed to accept sound waves as input and convert them into electrical signals as output. Those output signals typically need additional conversion before being fully inputted into digital systems.
While it is possible to use a microphone in reverse as a speaker output device, it goes against the mic’s intended design. Stick with mics as inputs and speakers as outputs for best results!
Understanding the input and output concept is key to effectively implementing microphones in your recordings or live productions. Now that you know mics start the signal chain as inputs, you’ll select and use them more effectively.