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Fostex is not a word that immediately comes to mind when you think of headphones, but perhaps it should.

The recently released Fostex TH909 Premium Stereo Headphones are getting some raves from audiophiles and in pro-audio circles. These latest headphones from Fostex are the open back version of Fostex’s TH900mk2s, which were also well regarded, but a closed back design.

Fostex TH909 Premium Stereo Headphones

The Fostex TH909s were a nice surprise. The sound was simply superb, on a variety of program material that can really test the mettle of audio gear. While the physical design might not please everyone, as it is anything but understated, the sound, to my ears, was as good as I have heard from a pair of headphones.


Fostex TH909 Premium Stereo Headphones

  • Superior, sound on both high resolution and standard resolution files
  • Will show up any defects in the recording
  • Well-built and striking visually
  • No 3.5 mm plug or adaptor
  • Leather (or leatherette) bag, but no travel case

Fostex has been around since the 70s, notably in professional recording with multi-track reel to reel machines, and monitor speakers, and most recently with some digital products like DACS and headphone amplifiers.


Dynamic, 50mm

Operation Type:

Open back


25 ohm


100dB/mW (at 1kHz, 1mW)

Freq. response:

5Hz – 45kHz

Max Input Power:



390g (excluding the cable)


Detachable 3m 1/4” unbalanced stereo (model ET-H3.0N7UB)


Headphone Stand (model ST300), Carrying Bag

Retail Price:





Fostex TH909, headphones, open back, dynamic drivers, Headphone Reviews – 2019

I remember listening to playback of music in my days working in FM radio on Fostex monitors.

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The firm makes studio headphones, and more recently has offered some well received consumer headphones, built off of their knowledge of high quality audio. The TH909 Headphones I have under review encompass what Fostex has learned over the years and incorporated that into a really fine headphone that competes directly with the more well-known high-end brands.


The TH909 are flagship premium headphones based on the well regarded closed-type TH900mk2.  While keeping the same sound characteristic, the company claims to have further expanded and increased its sound field by adopting open back construction and adjusting the acoustic circuit design.

The TH909 looks very rich with its housing cover that uses a Lacquer Bordeaux finish. Set against the black metal adjustable headband, the TH909 is striking to look at, although those preferring something more subdued may not find it to their liking. Personally, I found it very attractive and well-conceived.

Fostex TH909 Premium Stereo Headphones

The headphones use 50mm dynamic drivers with diaphragms made from a mixture of bio-cellulose and inorganic fibers. The TH909 come with a 3 meter cable with Fostex’s proprietary connectors that mate to the headphones, and the other end terminates with a standard 1/4” headphone plug. You can get a balanced cable set, but that is an option and there is additional cost. The TH909s are comfortable, but like most headphones I would not want to listen for more than an hour or two. That’s not because of the sound, but just because having fairly heavy phones on my head for long periods is just not that comfortable. High quality headphones with large drivers are just going to be big, so expect to listen and enjoy the quality of the music, but I doubt you will want to make a whole day of it.

Fostex TH909 Premium Stereo Headphones

With an impedance of 25 ohms and a sensitivity of 100dB, the TH909s are quite easy to drive. Even my iPhone got the volume to listenable levels, but if you are serious about your listening, and at this price you likely are, drive them from a high quality headphone amp.

One nice feature is the headphones come with a headphone stand, something I’ve never seen included with a high end headphone. In a separate box you’ll find Fostex’s Model ST300 stand, which costs $69.99 if you buy it separately. It’s a nice touch. The stand isn’t fancy, but it would not disrupt the look of your listening room.

Listening Tests:

Let me preface this section of the review by saying that speakers and headphones are among the most difficult audio products to review. Unlike an amplifier or DAC which can be measured in a test bench for frequency response or distortion, headphones and speakers are the result of subjective design decisions. Speakers and headphones have a ‘house’ sound, a sound that reflects the musical taste of the designer. We’ve seen that in speaker designs beginning in the 60s and 70s, where ‘East Coast sound’ battled with ‘West Coast sound’. Even then, not everyone agreed what those particular ‘sounds’ entailed, but they were different and reflected the sonic ideals of the designers.

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That brings me to the TH909 Headphones. I hear no distortion, excellent dynamic range, wide response extending from the high frequencies down to the lowest bass. And in the low end, the Fostex TH909s really excel. I’m not sure if other headphones are holding back on the low end or the Fostex headphones are just very good at emphasizing it, but bass is clean and does not feel ‘pushed’ or out of place. It feels very natural, but it is the best bass I’ve heard from any headphone.

Dynamic range is excellent, and, as I detail below, percussion sounds are very realistic and have a ‘bite’ to the attack that is not something that is easy for a driver to do. I hear the same effect on plucked strings and guitars. This is very rare, first class performance.

Music listening

I listened to the TH909s on a variety of hardware, including the headphone output of an Emotiva XMC-1 fed by an Oppo 203 player rendering high resolution files from an attached hard drive. I also listened to a variety of SACD discs. Other listening sessions were through a Schit Magni headphone amplifier fed by a HiFiMan R2R2000 that I had in house for review.

Quiet Winter Nights with the Hoff Ensemble

Hoff Ensemble “Quiet Winter Nights”

Quiet Winter Nights with the Hoff Ensemble – A reference quality high-resolution presentation from 2L. Acoustic instruments and vocals will challenge any speaker or headphone. I used to play trumpet in an orchestra, sitting close to the percussion instruments, and the drums on this recording were startling in their realism.

When I switched to listen to some of my other headsets there was no comparison. The Fostex TH909s got the sound just right.

Miklos Rozsa - Three Choral Suites

Miklos Rozsa “Three Choral Suites”

Miklos Rozsa – Three Choral Suites – A hyper-realistic SACD from Telarc. It combines the Cincinnati Pops with the Morman Tabernacle Choir performing classic film scores from Rozsa, including Ben-Hur, Quo Vadis and King of Kings. Although not the most natural of recordings as the orchestra and singers were recorded at different times and in different venues, the dynamic range and frequency response are thrilling. The TH909s went deep while keeping the strings smooth and undistorted.

Symphony No. 3 “Organ" - Saint-Saëns

Saint-Saëns “Symphony No. 3 “Organ"”

Saint-Saëns: Symphony No. 3 “Organ" – Kansas City Symphony – Reference Recordings. This is another high resolution recording that will test any transducer. The low pedal notes of the organ, combined with a full symphony orchestra and a piano came through with a detailed soundstage, prodigious bass, and delicate high frequencies.


Fostex TH909 Premium Stereo Headphones

The FOSTEX TH909 is a world class headphone that let the original source come through without obvious coloration or distortions. Some listeners may want headphones that slightly modify parts of the frequency spectrum to arrive at a particular sound, but to my ears, and with a variety of program material, the TH909s never strained or appeared to modify the original source.

  • Beautiful Design
  • Superb sound at every frequency band
  • Open back design
Would Like To See
  • 3.5mm plug
  • Travel bag

The TH909s are reasonably comfortable, and the open back design enhances comfort. The design is striking, but is not subtle and some potential buyers may find them a bit over the top. I thought they looked unique, and appreciated the fresh design cues.

I’ve heard a lot of headphones over the years, and tested quite a few in detail. I’ve never heard a headphone that combined wide dynamics, the ability to reproduce percussion accurately, and could provide as solid a soundstage as the Fostex TH909s. Yes, it may just best other fine brands ‘micro-incrementally’, but it is those very slight advantages that make comparisons of high-end headphones so difficult and yet so rewarding.