HD 600

The HD 600 has been on sale since 1997. That's the most important thing to know about it, and it's the thing most reviews bury. Three decades of continuous production means Sennheiser has had time to refine the manufacturing, drive the cost down, build a worldwide spare-parts network, and accumulate enough field data to engineer something that lasts. Cables, ear pads, headband padding, even the drivers themselves are user-replaceable. A pair you buy today will outlast five generations of TWS earbuds.

About the sound. The famous "Sennheiser veil" is real — there's a slight upper-midrange softness compared to brighter modern designs. Most reviewers either deny it exists or treat it as a fatal flaw; neither is right. What's true: out of a phone or basic DAC, the HD 600 sounds politely dull. Out of a proper headphone amp with a clean source, the same headphones reveal a tonal balance that's neutral verging on the right side of warm — and the veil dissolves into what is, in fact, a remarkably uncoloured midrange. The 300Ω driver is simple, low-distortion engineering done properly; it just demands the right amp behind it.

For a reader graduating from £100 closed-back consumer headphones to a proper open-back, this is where the ladder starts. What every £500 headphone is trying to be — without sounding overdesigned.