In practice, the revamped nozzle filters don’t really change the tuning. The S12 siblings sound highly similar, and one would be splitting hairs to hear a significant difference in A/B testing (well, unless you have golden ears). As far as fit is concerned… ugh. I will complain about this until I simply stop adding the most subjective topic of fitment. For me these fit perfectly. The slightly angled nozzle helps these earphones to sit perfectly nestled in my ear, almost like they grew there. For you however, I have zero clue how they will work. The S12 Pro are a bright pair of IEMs; make no bones about it. They have moderate treble extension, sparkle, and air, but for longer listening sessions, treble-sensitive folk might have an issue. These planars were relegated to brief footnotes on audio forums and didn’t gain much mainstream traction. That is, until the 7Hz Timeless arrived, heralding the era of the planar IEM hype train.

Letshuoer S12 Pro Review - Mobileaudiophile Letshuoer S12 Pro Review - Mobileaudiophile

The aluminum housings are pretty minimalistic and feature a matte finish. Build quality is top-notch. The shells are fashioned from a five-axis CNC (computer numerical control) process, with a small L and R circle on the housings denoting the left and right sides respectively. The S12 Pro are tuned to a deeper V-shape. They have bigger bass and sound more “fun,” though the bass isn’t as tight and textured as on the Talos and can bleed into the midrange.

Stock Cable

Multiple vent holes on both sides are effective in alleviating negative pressure build up within the ear canal and thus protecting your hearing. The S12 PRO has a minimalistic industrial appearance with a smooth space-blue finish and excellent workmanship.

LETSHUOER S12 Planar IEM - Reviews - Head-Fi.org

The S12 PRO has the upper hand when it comes to dynamic contrast and bass impact while soundstage is a draw, the P1 MAX is somewhat narrower and less open but it has a sharper imaging and more accurate positioning. In using a newer nozzle filter that is what Letshuoer is doing to create a newer “pro” version by lowering these aspects for better balance but then you throw on a more resolving silver plated monocrystalline copper cable? You see what I am getting at? I suppose you have to be really into your cable pair ups to fully understand what I am talking about. Bright +more resolving cable = Brighter.It is boosted here but it mainly adds some kind of a metallic - artificial hue to the treble that being fatiguing. The S12P isolates about as well as any iem on the market. Nothing to write home about, let’s just put it that way. Honestly when music is playing you can’t hear anything but the music. I suppose these would be fine for out and about listening but don’t think they isolate the outside world like a proper ANC set. For myself I get a great seal and isolation is above average.