Headphones — ROSESELSA QT-X

The QT-X is a hybrid in-ear monitor sold under both the ROSESELSA and Rose Technics names. Each shell carries seven drivers in a 1DD plus 6BA layout, and the package includes a USB DAC dongle alongside the analogue cable. The regular list price is USD 389.99, with a sale figure of USD 319.99, and the earpieces come in Nebula Purple, Platinum Silver, Starry Blue and Obsidian Black.

Key specs that matter

A 10 mm dynamic unit using a liquid crystal polymer diaphragm and a Tesla-grade magnet works together with six balanced armatures per side. ROSESELSA splits the armatures into pairs - two 30018 units for the lower mids, two 29689 units for the upper mids and two 30019 units for the top octaves. Impedance is 18 ohm and sensitivity is 108 dB, over a rated range of 20 Hz to 20 kHz. The detachable cable uses 0.78 mm 2-pin plugs, measures 120 cm and ends in 3.5 mm or 4.4 mm terminations. The weight is given as 30 g with a tolerance of 3 g, and passive noise isolation is rated at 26 dB.

Engineering and use context

Rose Technics states that its acoustic team adjusted the phase of the dynamic driver between 100 Hz and 500 Hz to lower distortion in that band. The nozzle follows a deep double-bend path, which the company says limits reflections of high frequencies inside the ear canal while keeping the fit comfortable. Two editions exist. The Value Edition bundles a dongle built on the CS4398 chip, a 24-bit converter rated at 75 mW, 110 dB signal-to-noise and -103 dB THD+N, with PCM up to 192 kHz, plus the Grey Rose cable of dual-twisted 4-braided 8-core 5N single-crystal copper. The Deluxe Edition moves to an ESS9039Q2M dongle, rated at 300 mW, 126 dB signal-to-noise and -110 dB THD+N, with PCM up to 768 kHz and DSD512, and pairs it with the Blue Rose Pro cable of mixed 6N single-crystal copper and single-crystal silver in a dual-braided 4-core build.

Pairing

Being an easy load, the QT-X needs little voltage, so the bundled dongle is enough from a phone or computer, and a portable player with a balanced socket suits the second plug choice. Buyers who already own a DAC can pick the edition by cable and dongle rather than by earpiece, since the shells and drivers are the same in both. Balanced desktop headphone amplifiers can also drive it, using their lowest gain step.

Alternatives

The QT9-MK3 is the smaller Rose Technics hybrid, which combines a single dynamic driver with a quartet of armatures.