Sony IER-M9 In-Ear Monitor Headphones (Black)

Model: IER-M9 UPC: 027242913035 Item: 172238

$998.00 OR

Regular Price: $1,499.99

Save: $501.99 (33%)

Out of Stock

More Product Details

Our product experts are here to help

Questions? We're here to help.

Product Information

New Realm of Musical Expression on Stage

In-ear monitor headphones for a new realm of musical expression with advance audio technologies which includes Sony’s 5x unique Balanced Armature drivers, including magnesium alloy diaphragms and gold-plated terminals. Every musical nuance is authentically reproduced. Built with advanced responsiveness to detect the most subtle of music nuances, these headphones are unlike any other.


  • 5x Balanced Armature (BA) Driver Units
  • Magnesium alloy diaphragm super tweeter
  • Sony's original design BA Driver Units
  • Light and durable Magnesium alloy outer housing
  • Preformed ear hanger for stable fit
  • Magnesium alloy BA drivers for optimized sound path
  • 4.4mm standard balanced connection
  • Silver-coated oxygen-free copper cables for better signal transmission
  • Detachable cable for easy replacement
  • Performed ear hanger for ease and stability

5x Balanced Armature (BA) units for optimal sound design

For clean high notes, rhythm, pitch and the pure emotion behind every nuanced performance, the IER-M9 has 5x Balanced Armature (BA) Driver Units, including a Magnesium alloy super tweeter. 

Sony's original design Balanced Armature (BA) Driver units

The unique T-shaped Balanced Armature directly drives the diaphragm for a more linear motion and clean, faithful high notes. 

Magnesium alloy super tweeter 

The IER-M9 super tweeter diaphragm is made of light weight and rigid Magnesium alloy to deliver the responsiveness required for describing subtle music nuance. The unique BA unit design also benefits from extremely low resonance thanks to a high internal loss. Internal wiring is also upgraded, with a new silver coated copper voice coil and gold-plated terminals, to faithfully reproduce sound without sacrificing even micro signals – so pitch, harmonics, and emotion are portrayed. 

Audio grade film capacitor for less distortion 

Sony’s custom audio grade film capacitor in the cross-over circuit delivers much lower distortion than ceramic capacitors. Suppressing vibration and electric interference, the audio grade capacitor of the IER-M9 In-ear headphones delivers fine, relaxed sound. Plus, audio grade solder also helps minimize any loss in signal path. 

Integrated Magnesium alloy inner housing 

The BA units are held firmly in an integrated, high-rigidity housing. This helps to eliminate vibration and keeps sound clear and clean without losing even a micro nuance of sound. 

Optimized sound path

While standard BA in-ear monitors rely on a long and narrow flexible tube in their sound path, the BA drivers in the IER-M9 In-ear monitors use a wide and short sound path made of magnesium alloy. This reduces frequency peaks and dips, and gives the ideal frequency response to ensure a monitor sound you can rely on for critical listening accuracy. 

Balanced connection available

The IER-M9 In-ear monitors come with a 4.4mm standard balanced connection cable which separates left and right sound signals completely, unlike conventional headphone cables where both channels share a ground wire. This minimizes cross-talk and the resulting sound deterioration. 

Silver-coated OFC 

Silver-coated oxygen-free copper cables minimize resistance and signal-transmission loss. The result is less sound degradation, finer detail and smother treble sounds. 

Natural silk thread and non-magnetic undercoat plug

The IER-M9 uses natural silk thread as a cable insulator. This natural fiber works as a absorber against vibration and prevents rustling or bumping noises when you touch the cord. The gold plating of the plug has a non-magnetic undercoat which transfers the signal preserving subtle nuances. 

Light, durable Magnesium outer housing

Own the stage and the moment with the light, durable Magnesium alloy outer housing of the IER-M9 In-ear headphones. Stably fit and durable against knocks or accidents. 

Detachable cable

The cable is fully detachable so you can replace it if needed, or fine tune your monitor sound through a different cable. 

Preformed ear hanger for ease and stability

The IER-M9 In-ear headphones stably fit your ears through the universally shaped ear hanger. With firm fit and optimal housing shape, each ear bud stays in the right position. 

13 variation of ear buds 

Our earbuds come in thirteen variations – six triple comfort and seven hybrid silicon. So you can find a snug fit for all kinds of ear shape. Combining hard silicone rubber and specially-developed formed silicone, they perfectly match sound with stability and are comfortable to wear for long lengths of time. 



  • Cable type: Y-type
  • Driver unit: Penta balanced armature
  • Frequency response: 5Hz - 40,000Hz (JEITA)
  • Headphone type: Closed, penta balanced armature
  • Impedance: 20Ω (at 1kHz)
  • Plug: L-shaped non-magnetic gold-plated balanced standard plug
  • Sensitivity: 103dB/mW
  • Weight: 11g
  • Power handling capacity: 100mW (IEC)

What's in the Box

What's in the Box:

  • IER-M9 In-Ear Monitor Headphones
  • Clip
  • Carrying case
  • Cable holder
  • Triple comfort earbuds (SS/S/MS/M/ML/L)
  • Hybrid silicone rubber earbuds (SS/S/MS/M/ML/L/LL)
  • Warranty card
  • Operating instructions
  • Cleaning cloth


Customer Reviews for Sony IER-M9 In-Ear Monitor Headphones (Black)

4.6 / 5.0
9 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
Rated 5 out of 5
Comfortable and lightweight with Great imaging
I bought the Sony IER-M9 to pair with my Sony NW-ZX507. I enjoyed the warm lower-midrange sound signature, which is fantastic when listening to vocal songs. Comfortable to wear and listen for long hours.
October 23, 2020
Originally posted at
Rated 5 out of 5
I bought a month ago and love it. I used mostly with my 507
August 24, 2020
Originally posted at
Rated 5 out of 5
Amazing music representation
Bought these 8 months ago, and they sound better now then when bought. The music is even smoother then when new. Everytime I put them on, it blows my mind as to hearing instruments or sounds I literally did not hear in my previous earphones. The imaging is at the same level as my Bang Olufsen Beolab 5 home speakers. I have these earphones paired with my Sony NW-WM1A, which is another impressive piece of audio equipment. You won't be disappointed.
May 8, 2020
Originally posted at
Rated 5 out of 5
An Incredible In Ear Monitor System
The Sony IER-M9 is a professional IEM in a gorgeous magnesium casing. It feels very much like a premium product. It's lightweight and comfortable in the ear, and its memory wire is superb. Under the right conditions it feels like it disappears when worn. It's much lighter and more shallow than the top-of-the-line IER-Z1R.

The sound the M9 produces is tremendous. Bass is accurate and well separated. It doesn't extend too far unless the song calls for it. Mids are just right - not recessed and not too far forward to be fatiguing. Perfect for listening for long sessions. The highs are just as good as the mids. Smooth, not shrill. Overall the M9 has excellent resolution and detail. Soundstage could be improved, though in general the M9 produces what could be called perfect sound; presenting music in a forgiving manner even with lower bitrate files. Its frequency response is sure to be pleasing to any music lover.
February 23, 2020
Originally posted at
Rated 5 out of 5
So much details!
Excellent craftsmanship. After about 200 hours of burning in, it matches the ZX 507 really well.
January 3, 2020
Originally posted at
Rated 5 out of 5
Just Awesome
Hi my name is Chris and I am an earphoneoholic. My IEM of choice is the Sony IER-M9. I own/have owned iems from every vendor of note as well as countless 'Chifi' brands (mostly high end). The M9 is what I regularly use. They have it all, quality, fit & comfort, removable cable, and most importantly ideal sound. They are audiophile, analytical, and clear while still being musical and fun. They have great bass (deep & clean), very slightly recessed mids, and wonderfully clear highs/treble. Impressive soundstage. I love how the bass can thump without affecting the mids/highs. I love how detailed and clear the treble can reach without fatigue/sibalance. They are advertised for musicians but I enjoy them for listening to everything (music, videos, podcasts). They respond well to EQ. I have multiple quality dac/amps and the M9 pairs well with all of them. You really can hear the details with lossless music sources. Interestingly they also sound good/musical/fun with lower quality sources as well. I enjoy them streaming music or videos 'wirelessly' over bluetooth with the little earstudio ES100. They aren't cheap but for me they are worth it.
The Sony ier-m9's are just awesome.
August 7, 2019
Originally posted at
Rated 1 out of 5
ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie ugly piece of poopie
February 25, 2019
Originally posted at
Rated 5 out of 5
Most amazing headphone I've heard in my life
Owned this for two weeks now and it still surprises me and impresses me every day. I power this IEM from a Sony ZX300 from the 4.4 balanced connection and it's a perfect match. This IEM is a master of detail retrieval, tonality and soundstage. BA drivers aren't normally known for their good bass but Sony has hit this out out of the park. The bass on these are absolutely perfect. I would not tweak it in any way whatsoever. They are a little bass heavy I would say. Not a neutral headphone but a fun headphone that I can listen to for literally hours and hours with zero fatigue.

My journey with Sony poetable audio products began just 3 months ago with the wonderful MDR-1AM2, which I adore. I loved them so much that not long after I purchased the MDR-Z7M2. Fantastic headphone but not for me. I returned them and used that to partially fund my now beloved IER-M9.

The only con for me was I wish they had included an LL sized hybrid foam tip. They have an LL silicone tip, which is the only tips included that I can wear. I guess I just have huge gaping ear holes or something as even the LL silicone is slightly loose in my right ear. But they still provide a perfect seal and are extremely comfortable and when inserted properly, provide a solid and sturdy seal that I don't have to worry about falling out or even coming loose.

I've owned a lot of headphones and IEMs in my life and this one is my favorite ever. I adore it and will enjoy it for decades to come. If you can afford it, buy it. It's worth every bit of the asking price and can be had cheaper than retail.
January 24, 2019
Originally posted at
Rated 5 out of 5
My IEM Workhorse!
Bought the M9 two weeks ago. Am surprised at the audiophile quality for its price. Big soundstage, distinct stereo separation, has breath and depth, never-tiring sound texture for treble, mid’s and bass. It sounds as good as those priced at US2,000 and above.You know it’s a good IEM when you don’t feel tired of listening songs with it day in day out. I am using the WM1Z and Sony Kimber 4.4mm cable. I will be getting the IEM1Z and the DMP when it’s available in January. Thank you Sony again for producing such beautiful products!
December 6, 2018
Originally posted at


Customer Q & A

Have a functionality, compatibility, or otherwise product-specific question about this product? Ask it here! If you have a customer service or shipping question, please direct it to our customer service department

Start typing your question and we'll check if it was already asked and answered. Learn More
No questions have been asked about this item. Be the first!