HE-4 is the single end version of HE-5LE: very similar sound signature. Because HE-4 only have 50% magnet in HE-5LE, it is much lighter (350g).
HE-4 requires a powerful headphone amplifier to drive it. Our EF5 headphone amplifier can serve 2 watt per channel.
Spec
Frequency Response: 10 to 60 KHz
Impedance: 38 Ohm
Efficiency: 86 DB
Weight: 350 g
Accessories
Headphone cable (OFC) with 6.5 mm plug. Length 3 m / 10 ft
Balanced Portable headphone cable with 3.5 mm 4-pin plug. Length 1.5 m / 5 ft
Earpad for backup *1
Headphone cable connector *2