HD 650
HD 650
For over 30 years, the reference sound for lovers of neutrality — a legend in the world of headphones: the HD 650.
Sennheiser HD 650
Open-back dynamic reference headphone with a natural, musical, non-fatiguing signature
A Benchmark for a Complete Listening Experience
The HD 650 renders the subtle details in your music with the same ease as the highlights.
Sennheiser’s HD 650 is a reference-class stereo headphone that delivers a truly audiophile experience with an open, natural sound. Specially developed acoustic silk is used to ensure uniform damping across the entire surface of each ear cup. Lightweight aluminum voice coils provide remarkably fast transient response, while the wideband transducers offer a frequency response from 10 Hz to 39.5 kHz. The elliptical design naturally follows the shape of the ear and was engineered with great care to ensure long-term comfort.
The HD 650 features a detachable 3 m cable made from highly conductive OFC copper with low microphonics and low susceptibility. It can be used with powerful portable devices and truly shines on high-end home hi-fi components. Included are the detachable cable and a 1/4" to 3.5 mm adapter.
.jpg)
Highlights
- Top-tier open-back dynamic hi-fi stereo headphone
- Tight-tolerance systems (±1 dB), pair-matched and hand-selected
- Premium titanium/silver finish
- Specially developed acoustic silk for precise, uniform damping across the entire surface
- Specially modulated detachable cable made of highly conductive OFC copper with extremely low self-noise
- Ultra-light aluminum voice coils for excellent transient response
- High wearing comfort thanks to an elliptical design that follows the ear’s natural shape
- Can be connected directly to the highest-quality home hi-fi components
- The (high-)definition of smooth
- Balanced acoustics, luxurious construction, timeless design
Balanced Acoustics, Luxurious Construction, Timeless Design
The HD 650 has all the strengths of a high-performance sports car — without any of the quirks. Audiophiles love this open headphone for its musical, non-fatiguing sound that still delivers a high degree of detail. From the first note, your favorite tracks reveal their true potential. For hi-fi enthusiasts who value an engaging, refined presentation, the HD 650 is an instant upgrade.
Technical Specifications
| Speaker frequency range | 10 Hz – 41,000 Hz |
| Speaker sensitivity | 103 dB (1 V) |
| Impedance | 300 Ω |
| Total harmonic distortion (THD) | < 0.05% (1 kHz, 1 V) |
| Plug / adapter | 6.35 mm stereo jack plug |
| Adapter | 6.35 mm stereo jack plug to 3.5 mm stereo jack plug |
| Cable length | 3 m |
| Transducer principle | Dynamic, open |
| Weight | 260 g |
| Wearing style | Over-ear |
| Magnetic field | 1.8 mT |
| Article number (SKU) | 508825 |
Measurements
What does it mean?
The dashed black line represents the Harman target, a reference frequency response developed based on consumer preferences. The red line represents the measurement of the HD650. In practice, it shows how much the headphone’s frequency response deviates from the target. However, note that the target is highly smoothed, and it is not necessary to strictly adhere to the Harman target for a headphone to sound good.
The HD 650 has a bit of bass roll-off due to being an open headphone, but follows the Harman curve pretty closely for an even sound signature with a slight emphasis in the 8–9 kHz region. This makes for a very revealing listening experience — not boring, but flat in the best sense of the word. Also well suited for audio production.
Harman Research
The Perception and Measurement of Headphone Sound Quality – What Do Listeners Prefer?
