The name Fostex has become synonymous with quite a few things throughout their long history. The first thing I usually think of when I hear them mentioned is full range drivers or the DIY haven that is the T50RP. While those things will always remain, it won’t be my first idea of Fostex any longer. A few years ago I remember reading reviews of TH909, and while reviews were positive I wasn’t in the position to be able to try and buy a pair. Years passed and when I finally had the funds my mind had drifted towards different things. Recently, I had a friend who mentioned having a pair of TH909 he would lend me for review. I jumped at the opportunity to try a headphone I had previously forgotten.
Its hard to discuss either the TH909 or TH900 without mentioning the gorgeous cherry red finish. The cups are made from rare Japanese cherry birch and finished in a Bordeaux lacquer. Each cup is handmade at the Sakamoto Urushi Factory.
Continuing on their classic build is the lightweight frame that supports the cups. While the headband is not very padded the weight is a non-issue. The cups themselves and the rest of the frame is so light its hard to tell they are even on your head at times. The clamping force is somewhat gentle but enough to get a good seal.
As far as the actual drivers, the TH909 uses a 50mm Biodyna driver. While this is a proprietary driver with special magnets, many companies have been stepping into the world of biodyna drivers with their own take. Fostex focused on the magnets with a very high 1.5 Tesla magnetic flux.
They are relatively easy drive with both low impedance (25 ohm) and high sensitivity (100 dB/mW). This allows people to drive these from most sources.
To match their race car red finish, these headphones are high energy, fast, and powerful. Once they are on it’s hard not to keep listening. They really are incredibly engaging with great speed for a dynamic driver. While maintaining that engaging signature they are still quite well balanced and natural. I was expecting a more V-shaped signature from what I had hear of the TH900 but was pleasantly surprised. They do extend well to either extreme giving them an impactful low end and nice sparklet to the highs.
Starting with the midrange, the TH909 almost present themselves as mid-forward especially in the upper mids. Vocals are quite vivid and clear with great detail. Timbre is decent and pretty much on par with other options from this price class.
The low end is one thing I was looking forward to after seeing the “guilty pleasure” air surrounding the TH900. I don’t consider myself a bass head, and tend to prefer quality over quantity approach. The TH909 checks all these boxes for me. They extended impressively deep while never sounding sloppy. They keep tight control and present notes both punchy and quick.
The treble on the TH909 is definitely emphasized, and while I would call them a bright headphone its not over done or glaring. They do a great job of toeing a fine line of almost having too much treble energy and then stopping so its not too much.
Soundstage is one aspect were they perform more average. Its neither overly exaggerated nor too intimate. It extends enough outside of the head and has great imaging to place instruments well and add to the overall experience.
Listening to “Goat Rodeo Sessions” demonstrates that while these can be aggressive and exciting when the time calls they can also be delicate and precise. Nobody demands greater control than listening to one of the masters like Yo-Yo Ma. These headphones are able to keep up with the speed and allow me to pinpoint each instrument in space. When the beat picks up they transition to energetic and can be reeled back in when the tempo changes. The mix is kept clear and precise, and all instruments are well defined.
I tend to lean on Fiona Apple when evaluating vocals. Something about her scattered, crisp vocals really show the strengths of some systems. I went through the whole album not knowing what to expect but came away pleasantly surprised. The vocal presentation is authentic and vivid. On “Under the table” I was rewarded with an incredibly dynamic and energetic presentation. Her voice swirls around as she self-harmonizing.
Overall, I think the TH909 was quite a surprise for me. I went from being not quite sure what I would think to being confident on how they wanted to present the headphone. In recent years, there have been a few dynamics in the same price class (Focal, ZMF, Sennheiser) all of which I think bring their certain strengths to the table. However, none of which are quite as enjoyable to me as the TH909. They are lively and energetic yet capable of being refined and tasteful. The speed of the drivers was probably one of my biggest surprises as some dynamics have a harder time keeping up. These are an easy recommendation for almost anyone looking in the market.