5. FAQ (Frequently Asked Questions)
On this page you can find frequently asked questions on: "Headphones".
- What is impedance?
- What does the distortion specification mean?
- What is sound pressure level?
- Do I need open or closed style headphones?
- What is the difference between dynamic and electrostatic transducers?
- What is frequency range?
- I need DJ headphones. What features should I consider?
What is impedance?
Impedance is a measure of AC resistance (of components such as loudspeakers and headphones), measured in ohms.
What does the distortion specification mean?
The distortion level is the relationship between the original signal amplitude and unwanted distortion, measured as a percentage. In simpler terms: the lower the distortion, the purer the music.
What is sound pressure level?
The sound pressure level is a measure of volume in standardized conditions, given in decibels (dB).
Do I need open or closed style headphones?
Closed headphones seal the ear to the headphone better, offer better bass response, and block more external noise, but can become uncomfortable during long sessions.
Open headphones rest upon the ears more comfortably. They do not shield the ear from ambient noise, so they are safer to use outdoors. DJ headphones usually have a closed back design for extra bass and isolation.
What is the difference between dynamic and electrostatic transducers?
Dynamic transducers consist of a permanent magnet and a diaphragm attached to a moving coil, which transmits sound as it moves essentially a small conventional loudspeaker.
An electrostatic transducer works differently. Here the diaphragm consists of a thin polymer foil, stretched between two surface electrodes. The entire diaphragm is shifted evenly by oscillations in the signal, and is able to move so fast that the sound is produced very clearly with minimal distortion. This is because the transducer has a much lower mass compared to the magnet and coil in the dynamic system.
Electrostatic headphones are much more expensive and are used almost exclusively in the professional sector (apart from some high end hi-fi models which tend to be even more expensive). Consumer and DJ headphones are usually dynamic designs.
What is frequency range?
This refers to the range of frequencies that a pair of headphones is capable of reproducing. The range of the human ear extends from about 16Hz to 20kHz. The better the transmission range of the headphone/loudspeaker, the better the possible rendition of the music. Values that extend beyond the range of human hearing are not perceived directly, though debate rages over how their presence affects perception of the rest of the spectrum. Sound pressure level does not remain constant across the entire range, which is why the frequency range cannot be used as the sole comparison between different headphone models.
I need DJ headphones. What features should I consider?
The most important feature is a sufficiently high sound pressure level (SPL), in order to be able to hear above the external sound of a loud PA system, though a closed back design with good ambient noise rejection can allow monitoring at a lower volume level. Also, replaceable or washable ear cushions can help your headphones last for many years.