The Metalen PRO is a cabled hybrid earphone for musicians from BASN Audio that keeps that model's four-driver concept while changing the housing finish and the cable set. BASN positions it as a professional monitor for stage and studio work, where the closed metal shell provides passive isolation. It lists at USD 129.99 and comes in white, gloss black and sapphire finishes, and brown and light blue versions have also been listed.
Key specs that matter
Every earpiece carries two dynamic drivers of 10 mm diameter together with two balanced armature drivers. The dynamic units are arranged coaxially, with the armatures mounted in an array in front of them. Impedance is about 18 ohm and sensitivity is about 102 dB, with a stated tolerance of plus or minus 2 dB. The earpieces use detachable MMCX connectors, and both supplied leads end in a standard 3.5 mm plug. Each lead measures roughly 1.5 m.
Engineering and use context
The metal covers are shaped by CNC machining and then electroplated, a process BASN applies to raise corrosion resistance of the covers. The result is a mirror-polished, all-alloy body with a polished grill over the nozzle, which is of medium length. The all-metal construction makes the earpiece heavier than a resin shell, but the weight is spread across the ear. BASN supplies two cables - an upgraded silver-plated OFC lead for everyday listening and a silver fibre lead with an inline volume control and microphone for calls. The tip kit covers three shapes, namely single-layer silicone, triple-flange silicone and slow-rise memory foam, each in small, medium and large sizes, so the user can seal the ear canal properly. Also in the box are a T-shirt clip, Velcro strips for cable management, a cleaning brush, an MMCX removal tool, a 6.3 mm adaptor and a carrying case, and the earphones are covered by a one-year warranty.
Pairing
This efficient load lets the Metalen PRO work straight from a smartphone, a laptop output or a compact portable player, while the full-size adaptor connects it to studio headphone amplifiers, mixers, digital pianos and wireless in-ear receivers. The volume control on the fibre lead is handy when the source has no easy level adjustment. Because MMCX is widely used, replacement leads with balanced 2.5 mm or 4.4 mm terminations can be used with portable players that have those sockets.
Alternatives
The BASN Bmaster5 is a further BASN hybrid model, which combines one diamond-like carbon dynamic driver with four balanced armatures.