The HD 650 has been Sennheiser’s flagship audiophile headphone for several years now, but it is only recently that the firm decided to buck contemporary pricing trends to reduce the product’s list price from around $600 to $500. Sennheiser has been building very high-performance open-back headphones for years, so in a sense the HD 650 is an evolutionary design that leverages insights and know-how gleaned from the classic HD 580 and the critically acclaimed HD 600. Even so, Sennheiser says the HD 650 breaks new ground by offering a sound that “captivates your senses where you used to be a mere observer” and that “allows total immersion in an ocean of music,” and I would agree.
When you first put on the HD 650s you might feel a little like Indiana Jones discovering lost treasure because the Sennheisers manage to dig up delicate, extremely low-level textural and transient details that most other ’phones simply miss. Tonal balance is almost perfectly neutral and dynamics are highly expressive and—where appropriate—explosive. If there’s any downside to this headphone, it might be a tendency for upper mids and especially highs to sound analytical at times, meaning the HD 650s occasionally expose rough edges in records that other ’phones would probably gloss over.
As you might expect, the HD 650 prove particularly rewarding when listening to well-recorded material that’s rich in textural detail. A perfect example would be Holly Cole’s performance of the Tom Waits song “Take Me Home” from Temptation [Metro Blue]. The track opens with Cole softly whispering “here we go” to her sidemen before the music begins—a detail the HD 650s rendered with exceptional clarity, then expands, and then begins to unfold as bassist David Piltch and pianist Aaron Davis join in. The acoustic bass is recorded at high levels that can be tough to handle, but the HD 650s kept the low end perfectly but powerfully under control. What really floored me, though, was the way the Sennheisers nailed the subtlest of inflections in Cole’s voice, making the whole track come alive in the process. The Sennheisers consistently provided an up-close-and-personal view of the music.
Sometimes, though, this means getting more detail than you bargained for. On “You Were Always There” from Lyle Lovett’s My Baby Don’t Tolerate [Lost Highway], for example, the HD 650s reveal that both Lovett’s voice and Russ Kunkel’s cymbals are so closely mic’d that their sound can momentarily become hard-edged and aggressive—problems that other ’phones won’t always expose (probably because they can’t). My point is that the HD 650s are sonic truth-tellers, at times almost to a fault.
At first I found the HD 650s squeezed the sides of my head much more firmly than other ’phones did, but after experimenting with the Sennheiser’s sliding earpiece arms, I eventually found a position that was more relaxed, yet not overly loose. Hint: if the HD 650s grip your head too firmly, try lowering the earpieces relative to the headband.
The HD 650 must be considered one of the benchmark products— if not the outright “gold standard”—in it price class, because it does all things well while exhibiting few if any weaknesses. While there are a handful of ‘phones that can perhaps outperform the Sennheisers in one or two areas, few if any offer a more balanced and refined set of sonic virtues overall. Indeed, the HD 650’s only “shortcoming”—if you can call it that—is a tendency to sound almost hyper-revealing at times, owing to its accurate but slightly analytical-sounding highs. But it’s better to have too much clarity than not enough, right?