The HD 280 Pro is Sennheiser's most significant closed, around-the-ear headphone to be introduced in years. Designed to exceed the demands of the professional environment, the HD 280 Pro boasts extremely robust construction combined with the sound quality, modular design and aggressive noise isolation the necessary in the field. The unique collapsible design, combined with swiveling ear cups, offers maximum flexibility in any application.
Features
Closed, dynamic stereo headphones
Accurate, linear sound reproduction for critical monitoring applications
Optimum impedance ensures universal compatability
Space saving design features collapsible, rotating earcups
Up to 32 dB of ambient noise attenuation
Neodymium magnets for high maximum SPL
Single-sided, coiled cable with 3.5 mm mini jack with locking 1/4" adapter
Very comfortable, even if used for long periods of time
Rugged construction with user-replaceable parts
2 year warranty
Compatible (listen only) with latest generation of tablets
Professional DJ Headphones - Noise Cancelling Headphones
$99.95
Variants
HD 280 SILVER
Model #005327
$179.95
The HD 280 silver is a closed-back, circumaural headphone designed for professional monitoring applications. Although suitable for a very wide range of applications, the exceptional 32 dB attenuation of external noise makes the HD 280 silver particularly suitable for use in a high-noise environment.
When one speaks about headphones, the emphasis is on such things as sound quality and frequency response. There is rarely any mention of the connection cable. Most Sennheiser headphones are fitted with an OFC (oxygen-free copper) cable. This ensures linear and low-loss transmission in the broad frequency spectrum of the headphones. Many Sennheiser headphones also have detachable cables, which make it very easy to replace them.
Contact pressure
The wearing comfort of a set of headphones is determined not only by its weight but also by the force with which the earpieces are pressed onto the ears. This force is given in newtons (N), whereby 1 N corresponds to the compressive force which a mass of about 100 g exerts on a solid surface. The DIN Standard 45500 Part 10 limits the maximum permissible contact force to 5 N. Values of between 1.3 and 4 N are common, although lower values apply for open headphones. Higher values can be found in the case of closed headphones. Here, a higher contact pressure is required in order to achieve sufficient sealing, which is important for the reproduction of low frequencies.
Ear coupling
A distinction is made between headphones which are worn on the external ear (supra-aural) and those which surround the ear (circumaural). Open headphones have foam ear pads that rest on the ears or ring pads that surround the ears. Closed headphones, on the other hand, nearly always have circumaural ear pads.
Frequency response (headphones)
The frequency response of a pair of headphones is given within limits defined by the manufacturer.
Jack plug
A common audio connector in consumer electronics and music industry. Available in various diameters; in the hi-fi segment, 1/8" and ¼" are widely used. Poles range from one to four. (Examples: headphone jack or jack of an electric guitar).
Load rating
The load rating is the amount of electric power which - according to the manufacturer´s specifications - can be continuously supplied to a set of headphones over a period of time without causing damage. According to DIN 45500 Part 10, the load rating must be at least 100 mW. Testing is carried out using a special noise signal which is supplied to the headphones over a period of 100 hours.
Nominal impedance
See impedance.
Sound pressure level (SPL)
Due to the impractical numerical values, the sound pressure is usually given as the logarithmic value of the sound pressure level according to the equation: dB SPL = 20 x log (po / 0.00002 Pa). The abbreviation SPL (sound pressure level) is added in order to make a clear distinction from other uses of dB. The reference sound pressure, which is at the same time the threshold of hearing, is then 0 dB SPL. The threshold of pain is 140 dB SPL. A difference in the sound pressure level of 1 dB is just about perceptible, while a doubling of the sound pressure corresponds to 6 dB and a doubling of the volume corresponds to a rise of 10 dB.
Total harmonic distortion (THD)
Total harmonic distortion is a measure of non-linear harmonic distortion and is given in %. Non-linear harmonic distortions are signals which were not present in the original before the signal was converted by the headphones. These unwanted signals are caused by the diaphragm, whose movements do not precisely move in time with the electric signals that cause it to move. Unfortunately, this is a feature of all electroacoustic transducers. Although it cannot be completely eliminated, suitable steps can be taken to minimise it. However, the user is not interested in why this distortion takes place but in how great the level of distortion must be for it to become perceptible. According to the findings of several research projects, a total harmonic distortion of 1% in the frequency range of 100 to 2000 Hz is imperceptible. Below 100 Hz, the perceptibility threshold lies at 10%.
Transducer principle
Two transducer principles have become established for the conversion of electric energy into mechanical energy: electrodynamic and electrostatic transducers, whereby the latter is only to be found in audiophile systems, due to their relatively high manufacturing costs. Electrodynamic transducers basically consist of a ring-shaped permanent magnet and an oscillation coil, which is fixed to the receiver diaphragm. When an audio-frequency alternating current is passed through the oscillation coil, it is caused to vibrate in accordance with the audio-frequency alternating current, thus causing the diaphragm to vibrate in the same way.
