Personal Audio
HD 650 - Sennheiser USA
Article No. 009969
Key Features
- Balanced & transparent sound
- Elegant titanium-silver finish
- Optimised for minimum distortion
High Quality Headphones - Around Ear Headphones
$499.95
Related product
$499.95
General Description
In the HD 650, audiophiles will experience truly unique natural sound. With sound this good, long concerts in the comfort of your home are a certainty, so the HD 650 also sets standards in comfort and convenience. The HD 650 is a genuine masterpiece, which will satisfy even the most demanding listener. HD 650 – the Reference Class..
Features
- Top-of-the-range open, dynamic hi-fi stereo headphones
- Systems with narrow tolerances (± 1 dB), hand-picked in pairs
- High-quality titanium/silver finish
- Specially developed acoustic silk for precise, uniform attenuation over the entire area
- Specially modulated connecting cable (detachable) made from highly conductive OFC copper, Kevlar-reinforced, with very low handling noise, i.e. low structure-borne sound sensitivity
- Extremely lightweight aluminium voice coils ensure excellent transient response
- Exceptionally comfortable to wear due to elliptical design adapted to the shape of the ears
- Can be directly connected to stationary hi-fi components of the highest quality, in particular SACD, DVD-A and CD players
- Built-tough with a 2 YEAR warranty
$499.95
Technical Data
| Cable length | 9.8 ft. (3 m) |
| Contact pressure | Approx. 2.5 N |
| Ear coupling | Around-the-ear |
| Frequency response (headphones) | 10.....39,500 Hz |
| Jack plug | 6.3/3.5 mm stereo |
| Nominal impedance | 300 Ω |
| Sound pressure level (SPL) | 103 dB (1 Vrms) |
| Total harmonic distortion (THD) | 0.05 % |
| Transducer principle | Open, dynamic |
| Weight w/o cable | Approx. 9.2 oz. (260 g) |
$499.95
Recommended Accessories
| Part/Accessory | Article No. |
| Ear cushions | 050635 |
|
Ear cushion, pair. |
|
| Headphone cable | 092885 |
|
Headphone cable, 10 ft, with 1/4" (6.3 mm) plug. Fits HD 650, also fits HD 600/580/565/545/535 |
|
| HH 10 | 510615 |
|
Headphone holder for all over-the-head style headphones. ships with any new HD485 or HD595. |
|
| Plug adapter | 092595 |
|
Adapter, 6.5mm female to 3.5mm stereo phone 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). |
| 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. |
