Sennheiser HD 400
These HD 400 (also written HD400) headphones were manufactured by the Sennheiser Corporation. Here are some of its features and specifications.
- Open-air
- Frequency Response: 20 Hz to 18 kHz
- Impedance: 600 Ω
- Nominal SPL (DIN 45 580): 90 dB
- Mass without cable: 80 g
- Cable length: 3 m