Headphone amplifier

Consumer headphone amplifiers are commercially available separate devices, sold to a niche audiophile market of hi-fi enthusiasts.

These devices allow for higher possible volumes and superior current capacity compared to the smaller, less expensive headphone amplifiers that are used in most audio players.

This allows headphones of a low sensitivity to be driven louder as a result of the extra voltage provided by the amplifier.

In 2008 Stereophile Magazine published an article that showed that a 120-Ohm output impedance could cause a 5-dB error in frequency response with certain types of headphones.

However, the author of the article also states: "The ramifications for subjective assessment of headphones are more troublesome because it is usually unclear what assumptions the manufacturer has made regarding source impedance.

For those who are electronically inclined, the low-power and fairly simple nature of the headphone amplifier has made it a popular DIY project.

The simplicity of the CMoy makes it an easy build, while it can be made small enough to fit inside a tin of breath mints (including batteries).

The introduction of digital signal processing (DSP) technology led a number of manufacturers to introduce amplifiers with 'headphone virtualization' features.

In principle, the DSP chips allow the two-driver headphone to simulate a full Dolby 5.1 (or more) surround system.

Headphone amps with sub-mixing capabilities allow the listener to adjust, mix and monitor audio signals coming from multiple sources at the same time.