The LETSHUOER S12 Ultra is a technically impressive planar IEM that delivers excellent resolution, speed, and tonal balance. The 14.8mm planar driver provides fast transients, clean decay, and very good micro-detail retrieval, especially in the upper mids and treble region.
The soundstage is wider than average for an IEM, with strong stereo separation and accurate imaging. Vocals are well-centered and slightly forward, maintaining clarity without sounding shouty. Instrument layering is clean, and the overall presentation feels controlled and refined rather than exaggerated.
Bass performance is tight and textured, focusing more on sub-bass extension than mid-bass punch. It does not emphasize impact aggressively, which makes the tuning more accurate and fatigue-free, especially for long listening sessions.
Build quality is excellent and feels premium. Comfort is good once the correct ear tips and nozzle angle are found, which significantly affects the perceived soundstage and tonal balance.
Cable note:
I also purchased an additional USB-C cable with an integrated microphone for convenience. While it works well for calls and daily use, it does not deliver the same sound quality as the original cable. The sound becomes more bass-emphasized but loses some soundstage width and fine detail compared to the stock cable. For critical listening, the original cable clearly performs better.
Important note for buyers in Türkiye:
For customers purchasing from Türkiye, please be aware that this product may incur significant additional customs taxes. In my case, approximately 17,320 TL in extra taxes and fees were applied, which substantially increases the total cost.
Overall, the S12 Ultra is a highly resolving and well-tuned planar IEM that will appeal to listeners who value clarity, speed, and balance over exaggerated bass. Strongly recommended for audiophiles who understand planar characteristics and proper fit.
