The HD 4.40 BT was made to go places with you – and make these places more pleasurable. With its around-ear design and deep, ergonomically designed ear pads it offers unmatched comfort even during extended listening sessions. Its robust foldable headband design that can be easily and compactly stored in the supplied protective case makes for perfect portability.
Specifications
| Impedance | 18 Ω |
| Frequency response (Microphone) | 100 - 10,000 Hz |
| Frequency response | 18 - 22,000 Hz |
| Sound pressure level (SPL) | 113dB (Passive: 1kHz/1Vrms) |
| THD, total harmonic distortion | <0.5% (1kHz/100dB) |
| Pick-up pattern | Dual omnidirectional microphones |
| Battery Specification | Li-ion Polymer Battery |
| Codecs | AptX |