Fostex's TH-610

After reviewing their flagship, the TH-900 Mk II, Fostex followed up with another of their biodynamic closed-backs, this time the TH-610. It occupies a much lower price bracket, at around $600. With a visually different style, but a somewhat similar sound signature, I think that these could be a great deal at the price, if you're a fan of the sound signature.

Fit and Form

Fostex has taken a bit of a different design approach with these than they have with the TH-900, at least in terms of style. Build-wise, they are very much the same, with the same size cups, same 2mm gap between the cup and the actual chassis, same hinge system, and same headband. However, the cups themselves are different. These use black walnut with a matte finish, as opposed to the elegant, but somewhat overt, Urushi lacquer of the TH-900s.

The connectors at the ear-cup are, again, the same, using a 2-pin connector that I have only otherwise seen on the TH-900, although I believe that these are the same ones used on Sennheiser's HD 600. The cable is pretty much exactly the same - fabric-covered, and very long. It is somewhat microphonic, but with music playing, that wasn't an issue. The connector at the amplifier-end is a 1/4" TRS auxiliary connector, with the same Fostex branding as the TH-900, although this one is matte, as opposed to the shine that the other connector has.

Comfort is very good, better than the TH-900 (and apologies for so continually referencing it). The pads used have an ovular opening that is fatter at the back-side, making them very comfortable. The clamp is just right for their weight, with the headband evenly distributing the weight of the relatively light headphones across the skull. The adjustment system, for length, clicks well and doesn't move unless it is moved by the user, thankfully. The hinges rotate well, and I really had no comfort issues at all with these headphones. The pads have been so comfortable that, after trying them for a little bit on my personal TH-900 Mk II, I'll likely be buying a set for them in the future.


These take a slightly different approach to music than the TH-900 Mk II does, as one would expect. I noticed that they do lack a little bit of the immediate "awe" factor that I noticed with the TH-900, but this post is not for comparisons, so I will try to avoid discussing that further. Bass is tight and fulfilling, with great slam and punch, as would be expected from a biodynamic driver. Mids are ever so slightly recessed and a little bit smoothed over, but otherwise portray vocals and instruments with good detail and fidelity. The treble is fairly smooth, but doesn't create a massive sense of space. I'll go into more detail in the specific frequency range sections in a moment.

The soundstage is very similar to the TH-900 Mk II, which is very good for a pair of closed-backs, but not quite rivaling good open-back models. It extends fairly far out, with pretty good height. Imaging and separation are both good, but not exemplary, lending a very cohesive sound to the headphones on the whole.


Songs used: Side B (Dope Song) by Danny Brown, Three Ralphs by DJ Shadow, and Viol by Gesaffelstein

Bass is unarguably the emphasis of these headphones. Sub-bass reaches very low, with great volume, lending songs like "Three Ralphs" a very punctual rumble that really shakes. Mid-bass has about the same emphasis, with bass guitars, kick drums, and electronic sections in the low end having great impact and definition. Thankfully, it isn't slow in the slightest, meaning that attack and decay in faster paced passages is not lost to the ether. This frequency range made for a very satisfying listen, as it gave a certain weight to most music that I put through these headphones.

Key descriptors: full, emphasized, and fast


Songs used: Scarlet Town by Chris Thile & Brad Mehldau, Find the Cost of Freedom by Crosby, Stills, Nash, & Young, and While my Guitar Gently Weeps by Jake Shimabukuro

Mids are slightly recessed, but not so much that vocals or instruments ever fade backwards. I appreciated this, as I've heard a lot of headphones recently where that is the case. They air on the side of lush, with a little bit of detail being obscured in the process. Compared to detail monsters like the King Sound KS-H3, they do miss some tiny details, like the exact sounds plucking of strings and the breaths between notes in sung passages. This isn't to say that this range is slushy or sloppy, as they still handle detail much better than most headphones I've heard. Additionally, they do a great job conveying the density and lushness of more complex and intricately layered passages, both vocal and orchestral. The imaging and separation, combined with the soundstage, allow for a very interesting stereo image to be created, which is very nice to hear in smaller-ensemble recordings, where it becomes very clear where each instrument is situated in the soundstage. I know this term isn't normally associated with this frequency range, but something that struck me with these headphones was that the mids,  particularly with acoustic instruments, are very impactful.

Key descriptors: lush, nuanced, and tactile


Songs used: Change of the Guard by Kamasi Washington, Ageispolis by Aphex Twin, and Seeds by palmlines

The treble is a little bit recessed, compared to the mids. This does lead the headphones to sound a little bit veiled, but it isn't on the level that some Audeze cans are, per se. There is still a good sense of detail, with cymbals coming through correctly, thankfully. Lots of headphones struggle with this, as the exact "tang" of a cymbal followed by its decay is a tough sound to convey with good fidelity. These do well here, although the muting of this range does restrain some overtones, leading to a slightly less realistic presentation of the timbres of instruments overall. This is me nitpicking, though, as it didn't particularly detract from my overall listening experience, which, if I haven't yet clarified, was very pleasurable on the whole.

Key descriptors: light, detailed, and restrained

Minutia and Miscellaneous

I don't have much to say here; Fostex fixed the comfort issues that I had with the TH-900 Mk II in this model, and crammed a whole lot of great sound into a headphone at a very reasonable price for what you get, in my opinion. In general, I think this is a pretty great package, and for anyone who can't quite make the jump to the TH-900, this seems like a very good option, as it retains a lot of the qualities of the TH-900, without sacrificing all too much.


There may be a bit of restating here, so bear with me. In sum, this is a very fun listen. Huge, impactful bass, without sacrificing mid-range emphasis and clarity. The mids, speaking of, are lush and fun, while still retaining a great sense of detail and touch. Although the highs are somewhat restrained, and that can have an impact on the portrayal of timbre, in whole, the sound still sits very close to natural, and is certainly an engaging listen. For anyone looking for something with the described sound signature, this may be your ticket. Plus, the comfort is absolutely stellar, which was essentially my only complaint from the TH-900 Mk II. These get a big thumbs up in my book.


These headphones were provided to me for review by Fostex. I am not being paid by anyone to write this review, to endorse the product reviewed, or for the content that I put in the review.

These headphones were powered by an Astell&Kern AK Junior, a Google Pixel, a Neurochrome HP-1, an iFi Pro iCan, and by whatever soundcard is in the motherboard of my computer.

I have had these headphones for about a month, and I have put about 35 hours of analytical listening through them during that period.

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