audio-sound @ hatena

An audio review & news blog. The volume should not exceed 80 dB is recommended. I usually adhere to the safe-listening style by WHO. Please note that my aural impressions and interpretations of measurements are also made from a safe-listening style.

(News) THOR Mjölnir MKII: An updater version of the first THOR model ever designed.




New IEM from THOR The THOR Mjölnir MKII is now available and will begin shipping after April 16, 2022.


Mjölnir is the name of the hammer held by Thor, the god of thunder in Norse mythology.



  • 12.56mm Fusion Diaphragm Dynamic Driver IEMs
  • Thunderous Bass, Brilliant Sound Details
  • 3D Designed Acoustic Chamber
  • Unique And Bespoke Manufacturing
  • High-Resolution Custom Silver-Plated OCC Copper Cable



About THOR

Driven by passion for audio rather than business growth, THOR has released only a handful of DIY-designed models - all of which have garnered praise from the few who have been able to get their hands on the limited releases. Every product is individually handcrafted and are available in limited stock. With a vision for paramount sound quality and bespoke character, THOR is committed to hand crafting each earpiece in small batches and continually innovating the field of in-ear monitors.


Thuderous bass, Brilliant detail

The Mjölnir MKII is the updated follow up to the first THOR model ever designed. Keeping in line with the original Mjölnir’s DNA, the Mjölnir MKII is a single dynamic driver in-ear monitor (IEM) specifically engineered to bring the best bass response in the industry.


The Mjölnir MKII features a never-before seen custom 12.56mm Fusion Diaphragm dynamic driver. The Fusion Diaphragm is a composite of DLC (diamond-like carbon), PEEK (polyetheretherketone), and PU (polyurethane) materials. Each of these membranes have been popular in the industry for their acoustic performance, but by combining them, the Fusion Diaphragm is able to harness the most optimal potential of each material. The DLC’s stiffness was selected to produce an incredibly punchy sub-bass impact, while the PEEK’s incredible thinness and responsiveness allows smooth and detailed mid-frequency playback. PU is not often used as a standalone material, but in composite settings, can provide beautifully sparkly treble that is airy and refined, with the added benefits of being easily tunable.


All of these components put together with an extremely powerful magnet capable of 1.6T of magnetic flux, the Mjölnir MKII makes for an exceptionally well-layered and coherent listening experience. With one of the most powerful bass response in the industry, the layers of separation between each instrument and frequency response still allows a refined and professional playback, suitable for stage bass guitarists and drummers. 



3D designed acoustic chamber

The tuning of the Mjölnir MKII relied more on the internal acoustic chamber design rather than typical dampening strategies used by dynamic drivers.


The acoustic chamber was 3D printed with a front micro-vent for pressure relief, reducing changes to the sound curve among dynamic driver IEMs often induced by internal pressure buildup. The rear acoustic chamber is also precisely designed to exact dimensions, and is fitted with a replaceable Knowles dampening apparatus, which is used in balanced armature drivers. This design allows for pressure relief, but also allows the user to change the rear dampening level by switching out the apparatus. The bass response can thus be effectively tuned to the needs of the user. 



The return of the legendary model that sold out in a flash

The original Mjölnir was only available as a 100 unit limited release, and sold out almost instantly.


THOR is made up of only a singular engineer who hand builds each unit as a DIY hobby during their freetime. Thus, each product is guaranteed to be unique and bespoke. It is a dedication and care for each specific unit that is rarely seen in the audio industry. The Mjölnir MKII will also only be available in limited stock. 




Replaceable Cable

The Mjölnir MKII comes equipped with a high-resolution custom silver-plated OCC copper cable that is replaceable. This allows the switching of cables to best fit the sound preference and comfort of the user, as well as ensuring the longevity of the IEM. 


Price & Availability

THOR Mjölnir MKII is now available at Linsoul and elsewhere for $369.