noise cancelling headphones, high attenuation of background noise
General Description
The closed-back HD 25-1 II purpose-designed, professional monitoring headphones offer high attenuation of background noise. Capable of handling very high sound pressure levels and of extremely robust construction, these headphones perform exceptionally well in high-noise environments, e.g. ENG, sound reinforcement, studio monitoring and audio equipment testing. The capsule is rotatable for one-ear listening. Ideal monitoring headphones for cameramen and DJs.
Features
- Very lightweight and comfortable, even if used for long periods
- High maximum sound pressure level
- 65 .nominal impedance for universal compatibility
- Tough, detachable steel cable
- Neodymium ferrous magnet systems and lightweight aluminium/copper voice
- Built-tough with a 2 YEAR warranty!
Delivery Includes
- 1 HD 25-1 II
- 1 adapter to ¼” (6.3 mm) stereo jack plug
- 1 Bag
- Soft ear pads (1 pair)
noise cancelling headphones, high attenuation of background noise
Technical Data
| Cable length |
Approx 5 ft. (1.5 m.) |
| Contact pressure |
Approx. 2.5 N |
| Ear coupling |
On-the-ear |
| Frequency response (headphones) |
16 - 22,000 Hz |
| Jack plug |
3.5/6.3 mm stereo |
| Load rating |
0.2 W |
| Nominal impedance |
70 Ω |
| Sound pressure level (SPL) |
120 dB (SPL) |
| Total harmonic distortion (THD) |
< 0.3 % |
| Transducer principle |
Dynamic, closed |
| Weight w/o cable |
Approx.4.9 oz. (140 g) |
noise cancelling headphones, high attenuation of background noise
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Article No. |
| 069417 |
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Velour ear cushion with foam disk, pair
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| 075527 |
075527 |
Donut style leatherette cushions for HME/HMEC25 series (also fits HME/HMEC45)
|
| 082370 |
082370 |
Threaded 3.5mm to 6.5mm phone plug adapter
|
| HD 25-02 |
040178 |
Replacement element
|
| HH 10 |
510615 |
Headphone holder for all over-the-head style headphones. ships with any new HD485 or HD595.
|
| HZL 25 |
040180 |
Replacement cable for HD25-1, terminates in right angle 3.5mm phone plug with adapter to 6.5mm.
|
noise cancelling headphones, high attenuation of background noise
Variants
| HD 25-13 II |
|
Model #502102 |
MSRP: $299.95 |
| HD 25-1 II, with 600Ω impedance, 3m steel cable, straight jack plug |
| HD 25-C II |
|
Model #502104 |
MSRP: $299.95 |
| HD 25-1 II with 3m coiled cable, straight jack plug |
Glossary
| Cable length |
| The cable length is usually measured between the anti-kink sleeves of the cable (cable length without connectors). |
| 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.
|
| 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. |