Sennheiser spent millions of Euros researching and creating the new HD650 in 2003, using technology created for its £1,000 MKH40 broadcast microphone to eliminate distortion and enhance clarity, while the sound balance was reported to be based on the Sennheiser Orpheus, which costs £10,000. It all added up to one of the company’s most popular hi-fi headphones of all time…
These phones are quite comfortable to use. They’re somewhat heavy at 260g, but they’re beautifully constructed with damped fibre frames, black stainless steel grilles, and a high-quality titanium-silver finish. Sennheiser’s unique Duofol transducers are used on both sides, with two Mylar sheets per side forming one stiff diaphragm and specially produced acoustic silk for accurate, consistent damping. The coils are made of ultra-light aluminium (Copper Clad Alloy Wire), with neodymium iron magnets in a sophisticated magnet/diaphragm combination that allows for regulated extended excursions with minimal distortion. Detachable three-meter connection cable constructed of highly conductive OFC copper for maximum signal transmission and Kevlar-reinforced for strength is used. This, according to Sennheiser, results in extremely low handling noise (i.e. sensitivity to structure-borne sound). As a result, the capsules are constructed to tight tolerances (within 1dB) and used in pairs that are hand-picked. Sennheiser claims a frequency response of 16-30,000 Hz (-1dB), using a 300 ohm impedance.
All of this would be pointless if it hurt to wear – I vividly remember Beyer’s DT990’s coiled cable giving me a lot of anguish as it continuously yanked at one side of my head! The HD650s, fortunately, are about as comfy as large hi-fi headphones get. The soft padding extracts a reasonable 2.5N of contact pressure, which isn’t as sylph-like as Sennheiser’s £29.95 PX-100s, but not bad!
They’re noticeably better acoustically than their HD600 predecessor. They start out quiet, which the ‘600s don’t, and then gradually open up and become more expressive as you listen to them. Daft Punk’s All Around the World demonstrated their musical prowess. The bass was slightly more powerful and rich than the HD600s, but it was also more fluid and articulate. With increased low-level detailing and a deeper feeling of ambience, the mid-band was smoother and more nuanced. But, once again, it was the gentler tone combined with greater expressiveness that wowed me. On jazz recordings like Herbie Hancock’s The Prisoner, this resulted in a more emotive listening experience — it was more alluring and enticing, rather than just plain ‘amazing,’ as the HD600s are. Another plus was the treble, which was far more impressive than the HD600s. It’s more atmospheric, ‘spacey,’ lucid, and slightly sweeter this time around.
They’re essentially pleasant, musical, and quite neutral, which is exactly how it should be. True, there are now more open and transparent designs available — the HD650s sound more cuppy and congested than they did at originally, reflecting increased competition from Audio-Technica and Philips. However, you still get a great sounding design that sounds much better with one of the many aftermarket headphone leads now available. Because of their popularity, these modern classic headphones are also a good second-hand buy, with prices ranging from £150 to £250; replacement earpads are roughly £50, so any HD650 you buy should last a long time.
