SonyIER-M9 in-Ear Monitor Headphones Black

Disclaimer: I am not an audiophile, musician, or sound engineer. My review is for general users.Received on December 23rd. Have been using for only two days.I have been using Shure e2c (e2c) for all these years. Since Apple Music has introduced Hi-Res Lossless music, I want to fully experience the marvel. After debating between Shure SE865 (865) and Sony IER-M9 (M9), I decide to get M9. M9 provides both balanced 4.4 mm and unbalanced 3.5 mm ends. At a similar price, M9 has one more driver than 865. For DAC, I use THX Onyx for its portability.I completely understand that it is unfair to compare e2c with M9, but that is what I have. I have a low-end Asus Cerberus gaming headphone and Apple EarPods with lightning connector, but they are a lot worse than Shure e2c. I also have Airpods Pro, but all bluetooth earbuds are lossy.When I use e2c and M9 to listen to the same lossless music, some instruments that I did not notice before with e2c become more obvious with M9. In other words, M9 provides more details in the music.M9 has stronger treble and bass than e2c for sure.M9 has a higher quality cable than e2c.M9 is much more expensive than e2c.Both e2c and M9 have strong mids.Both are comfortable to wear for a long time.Both have a similar level of noise-attenuation from external environment.E2c is louder than M9 with the same volume setting.Ironically, when I listen to another lossless music with M9/THX Onyx vs the default, build-in speakers of my MacBook Pro (16 inch, 2019), I can hear more details with the default speakers (set at 24 bits, 96 kHz) than M9/THX Onyx (set at 24 bits, 192 kHz). For example, I can hear the unintentional background noise in the studio during recording with the build-in speakers but not with M9/THX Onyx. When the musician slides his fingers on the strings of a guitar, the sliding is also more pronounced with the build-in speakers than M9/THX Onyx. Perhaps THX Onyx filters out some details?I then unplug M9 from THX Onyx and plug M9 directly to the 3.5 mm audio out (set at 24 bits, 96 kHz) on my MacBook Pro and got similar results. The default, build-in speakers of my MacBook Pro still provide more details than M9. Perhaps the 3.5 mm audio out loses some details?Just to be fair with M9, the bass of M9 is stronger than the build-in speakers.Lastly, I plug M9/THX Onyx to my iPhone. Yes, I have a lightning to USB camera adapter from Apple. THX Onyx LED changes color according to the sampling rate of different songs. M9/THX Onyx performs similarly as the two forementioned conditions.Bias: after spending a grand on M9, I feel obligated to give M9 five stars for every category on Amazon review.

These IEMS hit all the right spots for me. They have top notch technical capabilities in separation, layering, and resolution, audio reproduction with natural timbre, and a warm-neutral sound signature. Together, these allow the IER-M9s to produce a supremely enjoyable and exquisite listening experience across all genres.Concerning comfort, the preformed ear-hangers and the provided different sized ear-tips keep the IEMs stably perched in my ears with no difficulties. The connection between the cable and the IEM body can swivel, so there should be no issues with awkwardness of positioning of the IEMs. I have found it easy to quickly put on the IEMs and get a good seal (common advice is to pull the lobes of the ears backwards and upwards slightly).These also provide good isolation, having used them on flights (yes, you can't really experience 'audiophile' quality music on a plane, but from experience, they're definitely still significantly better than the Sony WH-1000XM4s and Bose NC700s).For reference, I own the IER-M9s and the Focal Clears (a pair of over-the-ear headphones), and I use them for about ~20h and ~40h a week, respectively, switching to the M9s during the evenings when I typically prefer a warmer sound signature or when I wish to read in bed. These are the priciest personal audio devices I have ever owned (but not the priciest that I have tried), and I have no regrets for either of them. I should point out that I am not too concerned with large soundstages in my devices as I have used IEMs and headphones with larger soundstages in the past and found that I was not impressed with what they did to my music with the exception of orchestral pieces. The M9s also produce a palpable and pleasant rumbling in the sub-bass frequencies (with no strange balanced armature flavoring that I can discern), though they are not considered bass-heavy when compared to other top of the line IEMs.NB: Some readers may not consider the IER-M9s "top of the line". Apologies for the abuse of language.

Maybe I'll go for over ear from now on

My reference IEMs are typically: Earsonic EM-9, Sennheiser IE-300, Shure 846, and Aurisonic 2.5. I prefer lively, dynamic sound, with a mildly analytical side.The Sony manages to have several high-water marks:1)Fine resolution of details: you will certainly find sounds in your recordings that you may not have found before2) staging/imaging: pinpoint. Instruments have excellent coherency and placement. Stage is deep, holographic, and only a bit narrow compared to the best.3) Tonality: Warm, but still resolving. Sound is non-fatiguing, but still visceral. Polite and smooth treble. Bass has weight and moderate 'slam'. Note edges are soft, rather than sharp, but not to the point of 'boominess'. Midrange is more dry than lush, but still conveys emotion. The midrange is the 'holographic' element of the soundstage. Treble, is extended but not sharp. Not airy, but also not dull. 'Balance' is the key word.4) efficiency: Ok, here is a problem for some....you need an amp to drive these to realistic levels. I use a Dragonfly Cobalt and it works fine. Anything less.....the sound becomes 'meh'.Summary: highly recommended for those who like to have the lively Rock & EDM, but also need something to handle acoustic performances. W-shaped signature and solid dynamics.