audio technica 2020 condenser recording microphone

Types of Condenser Microphones

Condenser microphones (or Capacitor) are generally considered to be of the highest quality and are used as recording microphones in the recording studio and in the television industry where a wide frequency response, high sensitivity and high electrical output are required.

The wide frequency response is needed to record all instruments and natural sounds that the human ear can perceive, the high sensitivity allows a wide dynamic range to be recorded (the quiet to loud sounds) and the high electrical output avoids having to add more gain in the audio mixer which would result in unwanted audible hiss.

Condenser microphones used to be considered too delicate to use in a Live Pop/Rock Concert situation and were exclusively used in recording studios and concert hall recordings, also they were very expensive. New manufacturing techniques and new manufacturers have enabled them to become cheaper and more rugged, though they still need handling with more care than a dynamic microphone.

Condenser microphones require a power source

Early condenser microphones had valves in them and required a high voltage external power supply, these ‘valve microphones’ are experiencing a resurgence in popularity for their different, slightly warmer sound.

Beyer large diaphragms condenser recording microphone

Most modern day condenser microphones (non valve) get their power from the three pin XLR plug that sends the signal from the microphone to the mixer, the so called ‘Phantom’ power is supplied by the mixer and doesn't’t affect the audio signal going in the opposite direction. It is typically 12 to 48 volts and a very low current whereas valve microphones need higher voltages and current, this is supplied down a multi-pin connector from a separate power supply box where the pickup pattern and any filters are also selected and where the audio is taken from, rather than directly from the microphone.

A power source is needed to supply a polarizing voltage between a fixed plate and the diaphragm, the movement of the diaphragm with respect to the plate creates a change in capacitance, this signal goes to the pre-amplifier which is incorporated into the body of the microphone and that needs power as well.

Microphone Diaphragms

The diaphragms used in condenser mics are not very robust and need careful handling, so they don’t get used in a Live situation except where a wide frequency response is needed e.g. Cymbals and Hi Hats.

Care should be taken to avoid large changes in temperature as this can cause condensation in the capsule, this results in a fizzing sound, if it has interchangeable capsules then the condition can be more pronounced. Allow time for the microphone to acclimatize - turn the phantom power on for awhile before starting recording. If you are recording for television then the camera will need to go through the same process to avoid the lens fogging.

Studio quality condenser recording microphone by neumann

Stereo microphones usually consist of two condenser microphones, sometimes electret microphones are used instead for economic reasons, e.g. in palm sized video camcorders while having similar characteristics to condenser microphones.

The longest established condenser microphone manufacturers include Neumann microphones (e.g. U87), AKG microphones (e.g. C414) and Sennheiser microphones (416), but there are more manufacturers such as Audio Technica microphones, Rode microphones and Samson microphones making a range of good quality condensers and helping to drive down their cost.

Large or Small Diaphragm Condenser microphones?

Historically condenser microphones had large diaphragms of about one inch in diameter. Strictly speaking these are more prone to resonance at some frequencies i.e. they tend to boost lower mid frequencies. These microphones are appreciated for their capability to ‘warm up’ vocals.

The smaller diaphragm microphones that were introduced in the 1960’s are used where a more faithful i.e. level frequency response is required.

Particularly with vocal recording there are no absolute rights or wrongs in microphone choice. Different microphones should be auditioned for each singer to achieve the sound you want.

Condenser Microphones Summary

Condensers are the most expensive type of microphones, though the cost has fallen dramatically in recent years, now some of them fall into the ‘affordable’ price band. They have the widest frequency response, dynamic range and a high output which makes them ideal for use where high audio fidelity is important.

A power source is required, this is cumbersome when the valve versions are used. Unlike dynamic and ribbon microphones they are not affected by large electromagnetic fields such as computer monitors.

Condenser mics are less robust than dynamic microphones and so don’t tend to get used in a Live situation. Neumann microphones and AKG microphones were best known for their condensers but new entrants to the field include Rode microphones, Audio Technica microphones and Samson microphones.