How Does a Condenser Microphone Work? Check Out This Simple Guide

How does a condenser microphone work? Here's a simple diagram to help explain.

Condenser microphones are the perfect type of mic to use when you want to capture a clear and well-defined recording. But just how does a condenser microphone work?

Sounds that have lots of high-frequency content are best suited to condensers – sources like vocals, pianos, and acoustic guitars. If you’re just starting to look into microphones for your own studio setup, I would recommend getting at least one condenser mic to start with, alongside a dynamic mic as well.




Condenser mics, also known as capacitor mics, are far more sensitive to higher frequencies than dynamic mics. They pick up a lot of the top-end detail of the sound you’re recording.

As humans, we can generally hear things in the 20Hz-20kHz range, and condenser mics can easily record these top-end frequencies. Dynamic mics tend to drop off around the 16kHz mark, losing that top-end detail.

If you’re looking to record something with lots of high-frequency energy, go for one of these microphones. You’ll also find some models that can record very low frequencies, a feature known as ‘extended low-frequency response‘.

As with all recording microphones, you should be aware of the ‘proximity effect‘. This is where the lower bass frequencies become louder when your sound source moves to within a foot of the microphone.

Over the years, I’ve generally used this type of microphone to record the following sources:

  • Voice
  • Electric guitar (a few feet away from the amp)
  • Drum overheads
  • Ukulele
  • Organ (for a crisp and clear sound)



How Does A Condenser Microphone Work?


The two diaphragms hold a fixed charge between them, powered by phantom power. The sound waves hit the front diaphragm which alters the distance between the two diaphragms. This changes the capacitance and hence the voltage level, producing an electrical output.


How does a condenser microphone work? Here's a simple diagram to help explain.

This output is boosted by the microphone preamp so the signal can be processed by other devices in the studio.




The transient of a microphone refers to how quickly it can react to an incoming sound. Condenser microphones generally react quicker than dynamic models, helping them to record a more ‘accurate’ picture of the sound as they can record across a wide range of frequencies.

But they are more sensitive to louder sounds – dynamic models are generally better suited to recording sources at higher volumes (due to the sound pressures involved).


Phantom Power


These types of microphones require phantom power to be able to record. This is a power signal of +48 Volts that’s sent to the microphone through the XLR cable, usually from the mixing desk or the sound card/audio interface. All it takes is the press of a button to turn it on. Some mics do have the option of using internal battery sources as well.




The size of the diaphragm is an important microphone feature too.

Large-diaphragm mics:

  • are commonly used for recording vocals, as they can add ‘warmth‘ to a sound.
  • should always be used with a pop shield, to help protect against plosive ‘P’ and ‘B’ sounds.

Small-diaphragm mics:

  • are often long and thin in shape.
  • generally provide a wide and even frequency response when recording.
  • lead to good transient response as well, making them suited to some drums and acoustic guitars.


Microphone Models


When it comes to picking up your own studio mics, there are some great models out there for any type of budget:

  • Up to $99 – Audio-Technica AT2020
  • $100-$200 – Audio-Technica AT2035
  • $200-$500 – Shure SM27, Rode NT1-A or Rode NT1000

Amongst the most famous condenser mics used in high-end professional studios are those made by Neumann, especially the U47 and U67 models. The AKG C12 is another with a big reputation.


Final Thoughts


Condenser microphones are perfectly suited to certain recording situations, that you’ll definitely encounter in your own home studio. I definitely recommend picking up at least one for your recording needs, two if your budget allows.

You should now also be able to confidently answer that all-important question – how does a condenser microphone work – given the above explanation into this vital studio tool.