What Is an In-line Mic?

Microphone Located on the Cord of Your Headphones or Earbuds

While shopping for new headphones or earbuds, you might have come across a company boasting that its product has an "in-line mic". This means that the device features a microphone that is built into the cable of the headphones, allowing you to answer calls from your smartphone or to use voice commands without removing your headphones.

Headsets that have headphones and a microphone that swings out in front of your mouth are not considered to have an in-line microphone.

Wireless headphones and earbuds may have an inline microphone embedded in the casing or connector band.

Controls for In-line Microphones

In-line mics also typically come with in-line controls that let you adjust the volume, answer and end calls, mute the audio, or skip tracks on your music player or smartphone. If you have a choice, the type of controls and ease of use can be an important factor in deciding which to buy.

The mute button may mute the microphone or the audio from your phone or music player, or both. Be sure to read the instructions to understand whether your voice is still being picked up by the microphone when you use the mute.

Often the volume control is done with a sliding tab or wheel, but it can be done with presses of a button to increment volume up and volume down. The volume control may only affect the incoming audio rather than the microphone output. You may have to adjust the volume of your voice going out by moving the microphone closer to your mouth or speaking louder.

The in-line controls may also have features specific for answering incoming calls from your phone, By pressing a button you can answer the call, which usually will pause or end playback from your music or another audio app for the duration of the call. You may be able to mute the microphone during the call, which is useful for conference calls.

You can also end the call using an end call button. Often, designs have only a couple of buttons which take on different functions depending on whether being used for playback or when you are using the microphone.

Compatibility Issues of In-line Microphones

Whether or not you can take advantage of all of the functions listed for the in-line microphone will depend on the type of device you have and the type of headphones you are buying. If you use an Android phone, for example, and the headphones you're looking at are Made for iPhone, the microphone will likely work but the volume controls may not. This can vary from model to model, so read the fine print first.

Features of In-line Microphones

Omnidirectional or 360-degree microphones will capture sound from any direction. The location of the microphone on the cord may have an effect on how well it picks up your voice or too much ambient sound.

Some in-line microphones are better than others for screening out noise other than your voice. In general, in-line mics are not of the highest quality and may not be suitable for sound recording.