The ultimate objective of modern headphones development is to reproduce sound that is as lifelike and direct as possible. That is also the aim of the engineers and acoustic developers at Sennheiser. For more than 60 years, the name Sennheiser has been synonymous with high-quality products in all areas of recording, transmitting and reproducing sound. The audio specialist from Wedemark continues to design and manufacture high-end headphones for the very highest demands, taking care to apply state-of-the-art and pioneering technology – and always driven by the ideal of achieving sound in perfection.
The milestones of headphones development
The history of high-end sound began with the HD 414. The world's first open headphones revolutionised the headphones market in 1968. For the first time, the ears could hear in a way that they are accustomed to: open and free in space. The sound can travel to the ear drum much more naturally and clearly than in closed models. With its new principle, the HD 414 triggered an absolute boom in headphones sales. More than 100,000 sets of headphones had already been sold by the end of 1969. Even today, the HD 414, which has long since gained cult status, is still the bestselling headphones in the world, with sales of over 10 million units to date. The open principle has also become firmly established in the development of high-end headphones.
A further milestone followed when Sennheiser engineers for the first time combined the principle of open headphones with that of electrostatic transducer technology. Sennheiser’s launch of the unipolar 2000 model in 1977 caused a sensation in the audio world. Its principle was once again an innovation in audio technology. In the electrostatic transducer, a high voltage is applied to two mesh-like electrodes. As in a loudspeaker, this voltage causes a coated foil diaphragm to vibrate in time with the audio signal. This results in an extremely fine resolution and low total harmonic distortion. “Its frequency curve has a relatively deep curvature from 2 to 4 kHz. This is one of the reasons why these headphones generate an extremely spacious, detailed, transparent, airy and nevertheless powerful sound image in unprecedented quality," was how one audio magazine ‘Hifi-Stereofonie’, sang the praises of the new headphones.
From a veritable flood of new headphones being introduced, one in particular stood out like a beacon in 1991: the electrostatic Orpheus HE 90/HEV 90. With the boldly ambitious mission to build the best headphones in the world, Sennheiser developers once again set to work – and once again exceeded all expectations of the audio sector with these electrostatic headphones and their impressive tube pre-amplifier. Two platinum-coated diaphragms vibrate between gold-coated glass electrodes. A 500 volt tube amplifier provides enough power to allow the Orpheus to fully unleash its sound. Due to the extremely complex technology involved, the Orpheus was produced in a limited edition of just 300 units. These legendary headphones still remain the ultimate benchmark for audiophile listening and for all high-end models that audio specialist Sennheiser continues to develop.
The Sennheiser high-end world today
The latest high-end products are all focused on guaranteeing perfect sound reproduction. The current highlight of this development is the HD 800. With this model, Sennheiser is taking up the tradition of the legendary Orpheus and has developed a set of audiophile headphones that offers the ultimate in reproduction precision and unique spatiality. The key component of these dynamic headphones is a 56 mm transducer. Its innovative ring design reduces distortion to a minimum even with a transducer as large as 56 mm, as the vibrating part of the diaphragm is not a circular surface area but only an annular section. Significantly less material thus results in less inertia and less additional vibration in high frequency ranges. The result: benefiting from total harmonic distortion of less than 0.02 percent (at 1 kHz and 100 dB sound pressure level), the HD 800 with its brilliant trebles and precise bass offers a sound image of unsurpassed clarity.
The HD 700 features a perfect combination of outstanding acoustic properties and sophisticated product design. Its styling and material selection have been thought through down to the finest detail in order to fully exploit the sound potential of the acoustic unit. The ear cups are designed in such a way that the sound waves are directed to the ears at a slight angle. This results in an impressively natural listening experience. The ear cups themselves have a completely open design. This not only ensures a highly transparent sound but also clearly displays the "heart" of these exciting headphones: the 40 mm Duofol transducer. Its powerful neodymium magnet systems guarantee detailed, lifelike audio reproduction from 10 to 42,000 Hz. To ensure that the acoustic properties of the headphones are not impaired by any partial vibrations, the transducer is mounted in a high-precision gauze made of stainless steel, as is the case in the HD 800 reference headphones. A new patent-pending feature is the special shape of the gauze, which continues the curved lines of the diaphragm.
True classics in the Sennheiser high-end world are the HD 600 and HD 650. Both models are open, dynamic, hi-fi stereo headphones with highly optimised transducer systems. Extremely light aluminium drive coils ensure excellent transient response, while neodymium ferrous magnet systems guarantee maximum efficiency. The HD 600 generates an exceptionally lifelike, spatial and accurate sound image with a frequency response of 12 to 39,000 Hz. With its deeper bass and pleasantly natural trebles, the HD 650 emphasis is on even greater expressiveness and emotion than the HD 600. The frequency response is 10 to 39,500 Hz.
With its new RS 220 wireless headphones, Sennheiser is opening up a new class of wireless listening. The digital wireless headphones guarantee a high-end sound image while offering total freedom of movement. The RS 220 transmits the audio signals without compression via a 2.4 GHz connection. To prevent interference during transmission, the transmitter uses what is known as frequency spreading. For a perfect sound experience, the RS 220 can be connected via various inputs: an analogue, a coaxial digital and an optical digital input. Discerning users can therefore decide themselves on the type and quality of the audio signal being fed in.
The IE 800 headphones from Sennheiser are the ones with the most innovations per square millimetre. The sound of the IE 800 can easily compete with that of the Sennheiser high-end portfolio. These dynamic in-ear phones offer fascinatingly brilliant trebles, precise bass response and a detailed, lifelike sound image with a frequency response of 5 to 46,500 Hz. The centrepiece is the specially developed Extra Wide Band (XWB) driver. With a diameter of just 7 mm, it is the smallest wide-band sound transducer currently available in dynamic headphones.
This year Sennheiser is launching its first amplifier for dynamic headphones, thus making the Sennheiser sound experience perfect. The outstanding features of the HDVD 800 include its balanced sound image, maximum precision and impressive spatiality. The digital HDVD 800 has a fully symmetrical layout and sampling frequencies of up to 24bit/192kHz to ensure an unequalled listening experience. It also harmonises perfectly with Sennheiser's HD 800, HD 700, HD 650 and HD 600 high-end headphones. A glass panel embedded in the aluminium housing of the amplifier gives a clear view of the top-quality interior of the HDVD 800. Selected components and sophisticated circuitry promise the ultimate in listening pleasure. The headphone amplifier is a further milestone in the history of development of premium audio products at the renowned audio specialist Sennheiser.
Shaping the future of audio and creating unique sound experiences for customers – this aim unites Sennheiser employees and partners worldwide. Founded in 1945, Sennheiser is one of the world’s leading manufacturers of headphones, microphones and wireless transmission systems. With 21 sales subsidiaries and long-established trading partners, the company is active in more than 50 countries and operates its own production facilities in Germany, Ireland, Romania and the USA. Since 2013, Sennheiser has been managed by Daniel Sennheiser and Dr. Andreas Sennheiser, the third generation of the family to run the company. In 2017, the Sennheiser Group generated turnover totaling €667.7 million.