From the September 1998 issue of Gramophone.

Ask the man in the street what kind of headphones he uses for serious listening and he will as likely as not answer Sennheiser, such has been the market penetration, as they say, of this German specialist transducer company. Sennheiser's success in this and, less publically, the microphone business is due to a combination of first-rate sound quality, very stylish presentation, deceptively robust construction and good value for money. In terms of volume sales, their biggest successes have come, naturally enough, with their budget models and few hi-fi enthusiasts will not recognise the distinctive yellow ear cushions which have until now been synonymous with this end of the range. Times change, though, and Sennheiser have decided on a revamped visual presentation for these new models.

At £26.99 the HD450 supersedes the HD4I0, while the HD480, at £36.99, similarly replaces the HD414. They are quite clearly two versions of the same basic design, having identical headband and earpiece chassis mouldings made, as usual, from a sturdy. black plastics material. The only differences here are in the lettering, which is maroon on the HD450 and silver on the HD480, and in the earpiece chassis which are left plain on the HD450 and are embellished with a metallic silver on the l-1D480.

Both are supra-aural as opposed to circum-aural types, which is to say that they fit on the ear rather than over it, and they are open-backed, using free-air rear loading of the drivers. This is in many ways the best approach, technically, since there are none of the design problems inherent in containing the unwanted rear-going radiation from the back of the driver. The penalties are that some, mostly high frequency, sound escapes into the room and that the wearer can similarly hear something of what is going on nearby. Many people prefer this sense of being in touch with their surroundings though and also feel much less of a sense of claustrophobia which headphone listening can induce.

The HD450 and HD480 offer a number of technical improvements over their predecessors. The diaphragms used are larger (although the overall cushion diameter remains much the same at around 80mm) and lighter than before, and new, more powerful, "Neodym-Iron" magnets have been used. The impedance of the coil windings has also been reduced to around 70 Ohms from Sennheiser's previous norm of 600 Ohms. Together, these changes have resulted in an improved transient response, a more extended bass and increased sensitivity, the latter relatively unimportant in most hi-fi applications where more than enough amplifier power is available but helpful in cases such as the 'Walkman'-type portable where the available voltage swing is somewhat limited.

As usual, Sennheiser have fitted a generous three-metre long lead which is both tough (stranded steel being used for the conductors) and flexible. Each model is fitted with a moulded 35mm stereo jack and supplied with a standard 625mm adaptor which is a push fit over it—a sensible arrangement which makes the headphones more or less universally compatible. Low cost Sennheisers have traditionally been very lightweight and comfortable and these are qualities which have been maintained here, for although the weight has increased a little to 135gm (about 4.75oz) from the 99gm of the HD414—which is still low—comfort has been enhanced with a soft covered-foam pad inside the headband. Very slightly concave, the ear-cushions are of acoustically transparent foam, now black. Damping material behind the drivers is covered by maroon fabric in the cheaper model and by a silver coloured wire mesh in the HD480. Left and right legends replace the colour-coded yellow and red cable strain-reliefs used before.

Sonically, these headphones clearly represent a significant improvement over their predecessors. During the last couple of years I have made quite extensive use of the HD414, finding it a useful tool for assessing the 'workings' of any given recording as an adjunct to normal listening via high quality full-range loudspeakers. Comparisons with the HD480 (taking careful account of their different sensitivities) quickly established the latter's superiority. The tonal balance is markedly smoother and more delicate and although at first one might be forgiven for thinking it a trifle dull, it soon becomes apparent, most strikingly on going back, that what is missing is one or two little wrinkles in the HF response. Pink noise can help pinpoint such deficiencies of course but one has to turn to a good recording of music itself to appreciate the qualities. A recently acquired favourite of mine is the 1983 Hyperion recording of Herbert Howells's deeply moving Requiem (Corydon Singers/Matthew Best, A66076, 8/83; (D CDA66076, 10/87, coupled with works by Vaughan Williams). Here the a cape/la singing is very revealing of any undue emphasis or deficiency and the HD480 came through this test very well indeed. At the lower end of the spectrum things are better too, with a more complete and convincing bass performance.

The cheaper HD450 has a response which leans towards treble emphasis compared with the HD480, which makes it appear more immediately 'dynamic' and punchy. This mild coloration is contrived to appeal especially to the youthful, pop oriented listener but the degree of compromise is slight and certainly not sufficient to render it unsatisfactory on naturally recorded classical material; it's good value at £2699 but I'd advise that you try before you buy. For 37 per cent more the l-1D480 provides a concomitant improvement in sound quality: it is a headphone which undoubtedly deserves to succeed in a highly competitive market. 

Specification

Frequency range: HD450 20-20,000Hz; HD480 18-22,000Hz. Impedance: 70 Ohms. Total harmonic distortion: less than 1%. Weight without cable: 135g. Plug: 35mm stereo jack plug with 625mm adaptor. Cable length: 3 metres. Manufacturer: Sennheiser Electronic KG, West Germany. UK distributor: Hayden Laboratories Ltd., Hayden House, Chiltern Hitt, Chalfont St Peter, Bucks SL9 9UG. UK retail price: F1D450 £26.99: f-f D480 £3699

Ivor Humphries