Product Description

HD 550

Your media is keeping secrets. No, not an encoded bitcoin key or Banksy’s real name — sonic secrets: the faint inhale of a singer, a fretboard squeak, whispered background vocals buried deep in the mix, faraway footsteps in an online game. The HD 550 headphones are your cheat code to hear them all — in brilliant detail and lifelike presence. And you don’t need a roomful of expensive equipment to access the experience.

• Nice and light (237 g) for long sessions
• Comfy low clamping force for your head and ears
• Your gateway to a new world of detailed, audiophile sound

Features

• Ideal for critical music listening, watching movies, remote work, and gaming — with microphone-ready design
• 150-ohm transducer (made by us in Ireland) for open, natural sound from 6 Hz to 39.5 kHz
• Enjoy extra comfort from gently soft ear cushions and headband
• Built to last, with replacement parts available
• Drawstring bag and 1.8 m cable included
• Open-back headphones with high-grade metal mesh earcup covers

A new world of detail and precision

Hear details you’d never noticed before. Feel like you’re right in the middle of the action. That’s what the HD 550 sound gives you in a light, comfy, accessible package.

Lots of mainstream audio products give you “bathtub” sound. They call it that because the frequency response curve is shaped like a bathtub. We like a nice soak as much as the next person, but with bathtub sound you’re drowning in bass and treble, vocals are weak, and certain frequencies resonate too loudly.

The HD 550 is the opposite — no gaps, peaks, or loofahs here. That means instruments don’t get “lost in the mix”. You can hear everything, and clearly. Deep sub bass reproduces frequencies you feel more than hear. Treble extends far beyond human hearing. Then there’s “soundstage”. Basically, high-end headphones make it feel like each sound is coming from a specific location. Not just left, right, or center, but also near and far, in front or behind you. Your ears do this 3D thing in real life, too. And with the right headphones, it works with recordings, games, and soundtracks.

What acoustic sorcery is this?

Getting a headphone design just right is a balancing act. It helps if you’ve been on this tightrope before.

Many modern headphones rely on electronics to achieve the desired sound. The HD 550, however, will have none of this: you get a direct analog signal path from source to ear. That means pure, unadulterated sound without additional noise or artifacts. This did put our engineers on the spot though: it meant the headphones had to be acoustically flawless.

They started with our excellent 150-ohm transducer inside the proven HD 500 chassis. We manufacture the transducer ourselves in Ireland, by the way, so you get outstanding quality and perfect channel matching. To create that 3D sound and wide soundstage, the transducers angle back towards the ears, mimicking real-life hearing. The dust cover is acoustically transparent. Even the ear cushion materials were selected for their acoustic properties. And a strategic bit of foam ensures smooth treble integration and controlled bass. The result is a neutral balance even our most demanding fans will appreciate. Open and airy, but never harsh, the HD 550 headphones are smooth enough to be anyone’s daily driver.

So light and comfortable they practically disappear

Has there been a contest for “most performance per gram”? If so, the HD 550 probably won. At just 237 g, they’re about as unobtrusive as possible.

The HD 550 design is heavily influenced by feedback from people like you. And you said, “make it light, make it comfy, and make it sound great.” So we revised the headband, using high-quality synthetic leather and softer foam. With such a low total weight, less clamping force was required. Which in turn allowed us to use soft, comfy earpads with plush velour. You get a fit that’s stable but so unobtrusive that even long sessions are no problem. Work, play games, or listen for as long as you like — without pinching, pressure, charging, or pairing.

But will they outlast my favorite band?

Depends who your favorite band is! Mick Jagger may very well be immortal, we can’t know for sure (Mick doesn't consult us on these things unfortunately). What we do know: people are still using Sennheiser headphones produced in the 1960s.

How can headphones from the days of the first “hip shake thang” still be going strong? Simple — German engineering and quality materials. And those haven’t changed. From the mechanics to the steel covers, our headphones are designed to withstand daily use or give collectors something to take out of a cabinet and dust every month for decades. You can get replacement parts like earpads for these headphones and many other Sennheiser products now — and years from now. And of course, all the accessories from our HD 500 range are compatible with your new HD 550 headphones.

Diving deep into the tech specs

Headphone frequency response graphs look very different from those for loudspeakers, which are ideally very flat. Here you can see a big rise on the right (treble) side and then it falls off a cliff. But this is in fact very close to what’s considered ideal for headphones. Because leading manufacturers base their goals on extensive psychoacoustic research about listeners’ subjective preferences.

For instance, it turns out that headphones negate the function of the outer ear, which otherwise amplifies sounds in the 3 kHz region. So, the ideal response for headphones is much higher there. Resonances in the inner ear also make sounds between 7 and 10 kHz louder, which is why the graph dips abruptly around 8-9 kHz. We can see here that the HD 550 builds on the already excellent characteristics of the HD 599, extending even further into subbass territory while still offering strong, analytic mids and brilliant treble without sibilance or harshness. The graph reflects the HD 550’s solid, satisfying bass response, balanced midrange, and precise and airy treble.