The first headphone that I’d ever dreamed of owning was the Sony MDR-R10. Released in 1989 with a production run of only ~2000 and an MSRP of $2,500 in 1989, they were a lofty goal for 12 year old me. Driver design issues that resulted in units failing has reduced that number to a figure I’d prefer to not know. Today, it’s not uncommon to see R10s sell for over $7,000, a price I personally can never justify, knowing that a small mistake can lead to me owning a $7,000 paper weight. However, ES-Lab, an electrostatic headphone manufacturer and repair center based in Hong Kong has released the ES-R10, their limited production attempt to revive the R10 in the modern era.
This is my second experience with an ES-Lab headphone. My first was the ES1a, which channeled the original Stax SR-Omega and remains one of my favorite electrostatic headphones. When I heard that they were creating the ES-R10 though, I was cautiously optimistic. While ES-Lab has been known to be able to repair Stax headphones and evidently has the capability to produce their own electrostatic headphones, manufacturing a dynamic headphone, much less one referencing a headphone with such a storied past, seemed like a lofty goal. I’ll preface this review by saying I have never heard a Sony MDR-R10, but I have owned an MDR-CD3000 and MDR-CD1000, both using Sony’s biocellulose drivers, though I cannot confirm the degree of similarity they have to the R10’s biocellulose drivers.
The ES-R10 comes in a lightweight paulownia wood box and a choice of cables: 6.3mm, 4.4mm, and XLR. I should commend ES-Lab for being able to implement SMC in an effective, secure way, something I assumed was possible, but ES-Lab proved. The tour unit I received had two sets of pads, but only one set, the shiny leather set in the photos taken, is included with the production unit. Thankfully, this is the set that I think sounds better by a noticeable margin. The build quality of the ES-R10 exceeds my expectations for the 12,500HKD (~$1650 USD as of December 2022) price point. The frame appears to be potentially a magnesium alloy, a Sony favorite, but feels sturdy. The cups look remarkably like the Sony R10 and is even made of the same type of zelkova wood the original R10 uses. In today’s market where manufacturers are able to release multi-thousand dollar headphones that feel unfinished, I don’t know how ES-Lab is able to release something that feels so polished for under $2,000.
Is it a true R10 clone?
I was given EARS measurements of the ES-R10 by ES-Lab compared to the original R10 and saw they didn’t have a significant amount in common other than a severe bass roll off. I would assume this is due to the soft, thin pads that don’t particularly seal well on my head and likely don’t seal well on a measurement rig. Given the unreliability of the EARS, I’ll refrain from posting the measurements so as not to release “bad” data. Those looking for an exact replacement for a broken pair of Sony R10s may not find that with the ES-Lab R10 but after hearing the ES-Lab attempt, I’m only more interested in hearing the Sony.
My primary testing setups with the ES-R10 were an Exogal Comet connected to a FirstWatt F5 and Questyle CMA800R. I did briefly try it with my Sony SCD-1 and Neurochrome DG300B but I don’t think it paired nicely with the tube amp, sounding even softer than my complaints later in this review.
The Standout Feature
The ES-Lab R10’s most interesting trick is that unlike many closed headphones that have a slight echo that sounds discordant, the ES-R10 reverberation is the closest I’ve heard to emulating the echo of a concert hall. It somehow sounds integrated with the rest of the sound and introduces a coloration that I find pleasant; it’s a direct opposite to the planar magnetic instant decay. If anything, decay can seem a little too slow and augmented which can be distracting with pop music but is an interesting presentation for chamber music. The buzzing of guitar strings lasts half a beat longer than I’ve heard it on any other headphone and I caught myself giggling at the novelty of the ES-R10’s sense of space given to it by this slight echo. This alone can be worth the price of entry for those who avoid closed headphones due to the lack of stage. While soundstage is towards the bottom of my priorities in a headphone, it’s such a triumph in that sense that I can’t help but acknowledge it. The trade-off is that the ES-R10 barely qualifies as a closed headphone: it is fully vented around the cups and playing them at my normal listening level (~80dB) yielded an amount of leakage that was roughly as much as a ZMF Atrium. The ES-R10’s ingress of external noise also certainly won’t cut it for a plane, though the size of the ES-R10 would take up more space than I’d want in a carry-on anyway.
The ES-R10’s treble is a mixed bag. I don’t know what material ES-Lab used with the ES-R10 but I do hear a little bit of hardness that I’m used to hearing from modern biocellulose drivers like the Fostex TH900. Air does extend quite well, especially for a closed headphone. This adds to the spaciousness of the sound and as a result, I often forgot I was using a closed headphone until I noticed the reverb. I do hear a bit of grain that grated on me the more I noticed it, but it wasn’t at offensive levels—about as much as a new Sennheiser HD600.
Other than the stage, this is what impressed me most with the ES-R10. It’s not quite as good as my Sennheisers, but it’s remarkably even-sounding. The closed market is rife with headphones with shallow cups that yield problems with backwave cancellation and as a result, dip lower midrange and color upper midrange. The ES-R10 avoids this, likely in part due to its deep cups. It leans a touch to the shouty side still with a subjective rise between 1kHz and 3kHz, especially compared to the much darker-sounding Aurorus Audio Australis, but the timbre was noticeably more accurate than most other closed headphones, and I’ve heard many of them, even off-the-radar ones like the Stax SR-4070 and AKG K872. I do have some gaps in experience, such as the newest Audio Technica and Victor models, but as an Audio Technica wooden headphone fan, I could only wish that the ones I’ve heard sounded as even as the ES-R10. I liked my Sony MDR-CD3000 for its forward midrange, but it was too nasal for most music, a characteristic towards which the ES-R10 only slightly veered. I don’t think it quite reaches the level of the Sennheiser HD580 in vocal timbre, but I’ve yet to hear anything that can. It has a slight boxiness and pinched nose effect to vocals that keeps it from truly shining, but for a closed headphone, it’s very solid.
Bass is the ES-R10’s weakest aspect. As mentioned earlier, the ES-R10 has significant roll-off. It extends slightly more than my Sennheiser HD580, which is known for its roll off. It’s also not particularly dynamic, which severely limits the music genres with which the ES-R10 plays nicely. I don’t want to call the ES-R10 anemic, as it technically has enough bass for most of the music I threw at it, but the softness of the bass does make them sound sleepy, bordering on uninvolving in that aspect. I’d certainly pick other headphones for EDM, for example.
The ES-Lab ES-R10 headphone is a product that appears to have a very specific audience: beyond those wanting to experience an emulation of the fabled Sony MDR-R10, the ES-R10 is best for those who prioritize midrange and treble, but are willing to deal with a little bit of coloration...and sound leakage. The spacious presentation is something I did not expect to be so enamored with, but it’s such an interesting effect that for the time I had the ES-R10, I had yet to tire of it. In fact, I’m heavily considering buying a pair for myself, in part because of the presentation, but truthfully, it’s such a pretty headphone it legitimately acts as a functional piece of art.