iBasso KLEE2 Earphones

The iBasso KLEE2 KiSEKi is a single dynamic driver in-ear monitor from the iBasso Jr. range. A 10mm driver with a lithium-magnesium alloy diaphragm sits in a polished stainless steel shell, tuned with dual Helmholtz resonators. It comes in Blue or Silver, with a silver-plated copper cable and both 3.5mm and 4.4mm balanced plugs.

The sound iBasso set out to make

iBasso describes the sound it was after like this:

• Controlled bass, with clearly defined drum hits.
• Natural treble extension, with harmonics gently dispersing into the air.
• Rounded sibilants, and a soundstage that is orderly in both width and depth.
• Vocals brought forward, with instruments in their own space.

A lithium-magnesium alloy diaphragm

The driver’s dome is a lithium-magnesium alloy. iBasso sums up what it brings in four words: light, for fast transients with no sluggishness, so every detail comes through precisely; rigid, to suppress diaphragm break-up and keep distortion low; stable, so it stays consistent; and smooth, for a natural tonal balance.

The 10mm driver uses a dual magnetic circuit with a magnetic flux density of 1.6T and a 0.03mm CCAW (copper-clad aluminium wire) voice coil. iBasso says this gives a crisp, well-articulated sound and an effortless presentation across the whole range.

Dual Helmholtz resonators

A Helmholtz resonator is a tuned air chamber that absorbs energy at a chosen frequency. The KLEE2 has two. According to iBasso they:

• cancel excess energy in specific frequency ranges, for a cleaner sound;
• tame harsh treble and excessive sibilance;
• smooth the treble and give the bass a taut, resilient quality;
• absorb and greatly reduce standing waves;
• create a spacious soundstage with a deep, quiet background.

Polished steel, in Blue or Silver

The shell is stainless steel with a polished PVD finish, in Blue or Silver. The gold-plated brass nozzle is removable. Each earpiece weighs 12.5g without the cable.

A silver-plated copper Litz cable, two plugs

The cable is silver-plated copper in a Litz structure, which iBasso says gives warm, smooth vocals and natural treble extension. Its nylon outer sheath helps suppress microphonics, the noise a cable makes when it rubs against clothing. It connects to the earpieces with standard 0.78mm 2-pin connectors, so other cables fit too, and the plug end is replaceable: 3.5mm single-ended and 4.4mm balanced plugs are both included.

Choosing eartips

Nine pairs of silicone eartips come in the box, in three kinds that iBasso has tuned to sound different:

Specifications

Good to know

• Try the three kinds of eartip and a few sizes: a good seal gives the full bass, and each kind changes the sound a little.
• The 4.4mm plug suits balanced players and dongles; the 3.5mm plug works with any ordinary headphone socket.
• For a small source in the same iBasso Jr. range, see the iBasso Jr. Macaron dongle; for another dynamic driver IEM from iBasso, the iBasso 3T-154; and for a step up in source, the DC07 Pro dongle.