How to resolve AdBlock issue? Fostex TH1100RPmk2
Update of the flagship magnetostatic headphone model
Author and photos: Peter Kaminski
We have already reviewed the TH1000RP and TH1100RP headphones from Fostex. In December 2025, Fostex announced an update to both headphones. On this occasion, we would like take compare the new TH1100RPmk2 open magnetostatic headphones with their predecessor and list the new features. It is therefore also worth reading the review of the previous model, which you can find here.
New features
Visually, there is only one difference between the TH1100RP (top left) and the TH1100RPmk2 (top right), namely the new connection via two 3.5 mm mono jack sockets. The previous connection variant was of a very high quality, but the plug type was unusual. Since both drivers are connected via separate jacks, the headphones can also be operated with a balanced connection. Thanks to the new plug type on the headphone side, the selection of cables from other manufacturers is now significantly larger.
As with the TH1100RP, a two-meter oxygen-free cable (7N OFC copper) of the same quality and length is included, which is equipped with a 6.3 mm stereo jack plug on the headphone amplifier side. With the ET-TH4.4BL2Y, Fostex offers a cable with a 4.4mm Pentaconn plug for balanced operation. For balanced cables with XLR-4 plugs, you have to resort to third-party manufacturers.
Another change comes with the ear pads, which now have a slightly different shape, fit the head a little better, and have a two-layer construction on the inside, i.e., a core and an upper section made of two different types of foam, which are then covered with synthetic leather.
The modification of the driver inside is completely new. Here, a flow adjustment was carried out with damping materials. The so-called “Air Dumping Control” was also submitted for patent in 2024. In conjunction with the new ear pads, this results in changed acoustic conditions.
In terms of specifications, i.e., weight of 420 grams without cable, impedance of 32 ohms, frequency range from 10Hz to 40kHz, sensitivity of 96dB/mW, as well as mechanical construction and design, the MK2 version is identical to its predecessor.
In practice
For the test, we had both the TH1100RP and the updated TH1100RPmk2 available for direct comparison, which we operated with the Lake People G108 and the SPL Phonitor 2. Since the data in the data sheet is identical to the previous model, we were curious to hear what audible changes there were. In terms of sound, the difference between the TH1100RP and the new MK2 version is clearly noticeable. The predecessor had a very linear sound and was restrained in the lower bass range - but I still found it to be well balanced. However, even good things can be improved. With the MK2, you notice that the signal components in the bass range have more punch without sounding significantly louder. There is simply more sonic volume, which particularly benefits the bass guitar and electronic drums.
I think they listened to user feedback from the US consumer market and accordingly made acoustic corrections. In a direct comparison, you'll probably opt for the new MK2. The bass range is particularly critical when listening with headphones. The new improvement has created a sound solution that will satisfy more users. The MK2 also makes it more enjoyable to simply listen to music, yet it is still absolutely ideal for mixing and mastering.
When it came to changing the connections on the headphones, I personally would have preferred mini-XLR, but the gold-plated mini jack plugs are also of very high quality.
Conclusion
The price has not changed compared to the previous models and is around €3,000 for the acoustically open TH1000RPmk2 and around €3,300 for the closed TH1100RPmk2. Advantages of this new model include the ability to connect cables with mini jack plugs, the modified bass reproduction, and an overall more musical sound that still offers high transparency and resolution. All in all, a successful update that should make the headphones even more interesting.