I have a soft spot for the Fostex TH900. It was the first headphone that broke me out of the idea that a headphone has to sound "natural" for me to enjoy it. The TH900, by most measures, is not a headphone many people would argue reproduces music in a realistic way. It's one of my touch points when someone asks for a "fun" sound. The TH900 has a lot of bass and treble with a bump in the center midrange to help with balance. It's a party condensed into a headphone. The open back version of the TH900, the TH909, added some alcohol to this party with, on my head, more bass and more treble. It was too much of a good thing for me. The recently released TH919 was purported to be a refinement of the TH909. This seemed like exactly what I was wanting from the original release. So, I decided to buy one earlier this year and after quite a bit of time with it, the TH919 does seem to rein things in significantly. Unfortunately, in trying to clean up its act, the TH919 seems to go a little too far.
Build
The TH900's successor, the TH910, is a downgrade in aesthetics for my taste with the removal of its platinum flake "FOSTEX" logo. But, the open TH909's grill size always looked awkward to me. The TH919's larger grills look much more cohesive, while still showing off the Urushi lacquer that Fostex uses for these headphones. This lacquer elevates the TH9XX series in my head to the point where I would consider them equal parts audio equipment and desk art.
Fostex has changed the swivel design from this infamously fragile design to a less complicated screw design. It doesn't seem immune to failure, as my pair did briefly come apart.
It was a trivial fix, with just a T4 screw bit and some blue threadlocker needed to prevent this from happening again, but I do wonder why there wasn't any threadlocker to begin with for such an expensive headphone.
Sound
The TH919 does retain the TH909's V-shaped tuning but interestingly, it does sound more controlled than I recall the TH909 sounding. The midrange and treble aren't nearly as grainy as I remembered from the TH909 but it does seem to have lost much of its character. The TH919 is a much safer tuning. This creates an interesting dichotomy where it's supposed to sound fun but... doesn't.
Bass
It's fine. It doesn't sound as bombastic as the TH900 or TH909 but it's a smoother transition from bass sections. This is technically a more "natural" presentation than the TH900's more hyped sub and midbass with dipped upper bass for more contrast. However, it's still quite elevated, so the balance is still skewed upwards. Subjectively, I do hear a little less texture in the bass due to this more smoothed presentation, which isn't exactly what I want from a headphone this expensive. It's easy to use the TH919 for background music, but the lack of engagement isn't necessarily something I desire from a flagship headphone.
Midrange
Less fine. The TH919 is very clearly a V-shaped tuned headphone but the combination of the recessed midrange and bass boost makes the TH919 sound a little too muffled for my liking with most music. The recessed midrange is less of a problem with bass-focused EDM, but for orchestral music, the balance of everything is way, way tilted to lower instruments. Timbre also seems to suffer due to this, as I notice instruments seem to have a little too much body and lack the sense of resolution I’d like.
Treble
The least fine! The treble peaks on the TH919 differ from those of the older siblings and seem to be pushed further up the frequency band and fatigue me quickly. I struggled to listen to music with them for more than an album at a time. While this is likely to shift in frequency and amplitude on different people, it’s severe enough that I don’t feel comfortable assuming it’ll coalesce better on other people’s heads. This is coming from someone who just positively reviewed a beyerdynamic headphone.
From what I am able to tolerate, it’s not as grainy-sounding as an uneven treble response typically is. But the elevation did make air and trailing ends of decay sound muffled in comparison.
Measurements
No real surprises with the measurements here: it's V-shaped with a fairly noticeable 1-2kHz dip, but actually seemingly less V-shaped than my ears hear it. The more interesting measurement is their impedance:
The TH909's impedance does look slightly different:
This actually does not seem to line up with Fostex's marketing material:
While the impedance curve in the bass is different and behaves more like a traditional dynamic driver, this actually seems like a step back. The TH90X headphones are some of the few dynamic headphones that were minimally affected by a high output impedance amplifier, but now I feel less compelled to do the same with the TH919, as the last thing this headphone needs is more bass. Unfortunately I also don't see an improvement in the midrange. In practice, I do think this is less audible than it appears.
Comparison
Versus Austrian Audio Composer
I only have one headphone here that I feel is a comparison that makes sense: the Austrian Audio Composer I was loaned to compare to the TH919. They are a natural comparison point to the TH919 as both are V-shaped-tuned flagship dynamic headphones. As someone that’s not often a fan of V-shaped headphones, it should be no surprise that the Composer has never been my cup of tea with both versions of pads. The velour pads do seem to help treble slightly, but the Composer still doesn't do it for me. In comparing back to back, I found something very interesting: the TH919 and Composer sound almost the same. On my head, they actually sound even more similar than the measurements may imply:
The main differences I hear are actually not that dissimilar from the differences between the Sennheiser HD600 and HD650. The TH919 has more bass and, for me, is smoother in the treble. The Composer puts vocals very slightly forward in comparison but does seem to bother me more in the treble. The similarity I hear between the two is actually astounding.
Conclusion
The TH919 falls in this awkward middle ground of attempting to make a more consumer-friendly tuning while keeping most of the colorations the original TH909 has. This leads to a worst-of-both-worlds situation where by smoothing over the rough edges, it loses most of its character. I understand why Fostex did this, as it does sound "better" than its predecessors. It's even likely that more people will like the TH919 than the TH909, but I find it hard to connect with the TH919. It's tuned to be fun and engaging but the actual presentation doesn't do anything for me. I find headphones more interesting when they're a hit-or-miss presentation rather than safe to a fault. I respect tuning decisions more even when I think they sound bad than tuning decisions that end up making a headphone sound mediocre to me. While I don't think the TH919 is a bad headphone, it's something worse: forgettable.
To close this review, the one thing that's pulling me towards keeping the TH919 is the beautiful Urushi lacquer. This may seem silly, but Fostex International may convince you that I'm not crazy: