Letshuoer S15
The S15 is Letshuoer's 3rd-generation 14.8mm planar with a passive 6mm R-Sonic filter, and approved coverage agrees it deliberately walks away from the bright, energetic S12 formula. The consensus is a rich, smooth, warm-leaning planar that prioritizes body and listenability over raw detail: bass has real weight for a planar, mids are full and relaxed, and treble stays polite. Reviewers praise it as a fatigue-free long-session set, while the recurring criticism is that resolution and clarity are only moderate for $329 and listeners expecting an S12 successor's energy find it subdued.
Moondrop Aria 2
The Aria 2 is a single 10mm dynamic driver IEM whose most concrete gains over the 2021 Aria are physical: a milled zinc alloy shell, a replaceable brass nozzle, a modular cable terminating in both 3.5mm and 4.4mm, and a leather-style zip case. It is easy to drive, carrying manufacturer figures of 122 dB/Vrms and 33 ohms alongside an impedance curve reported as effectively flat, so source pairing is not a concern. Tuning is broadly balanced with a mild U shape. Bench measurement shows a dip near 500 Hz, a consistent lift of about 3 dB from 1 kHz to 3 kHz, and extra energy between 3.5 kHz and 6.5 kHz. That upper-midrange lift is the most complained-about trait, drawing repeated descriptions of shoutiness. Coverage splits sharply on bass: one reading hears it as noticeably deeper and more extended than the original Aria, another hears very little sub-bass gain and prefers the first Aria there. Treble draws the same fork, read either as comfortably tamed and short on sparkle or as energetic with an audible 7-8 kHz peak that can turn sharp. Staging is called impressive for the bracket in some listening and merely average in other listening, and a measured immersiveness sub-score of 3.8 was the weakest of its three audio sub-scores. Comfort is generally good, though at 11.8 g per bud very small ears and pressure-sensitive listeners were flagged as at risk. Verdicts range from a clear recommendation in the bracket to a lateral refresh where the packaging does the persuading.
