Astell&Kern is best known for their industry leading flagship A&ultima series DAPs, like the SP2000 and SP3000, but they’ve also demonstrated innovation with models like the powerful KANN Max and the A&futura series SE200’s unique two discrete DAC channels. It’s sometimes easy to forget about the A&norma series which doesn’t offer the top of the line, exquisite sound and performance of the A&ultima series, nor does it provide the innovation of the A&futura line. Instead they take bits of the tech from the higher end players, and turn it into class leading designs at lower price points. At $799, does SR35 carry on the brand legacy and stand out among the best players under $1000?
Build and Design
With a quad-DAC and a new amp under the hood, it’s impressive that Astell&Kern has continued to maintain its compact form-factor with the SR35. Among high-end players, SR35 is one of the smallest, and also provides some of the best battery life, with an estimated 20 hours of continuous playback. In order to achieve this, some sacrifices need to be made: with the screen perhaps being first and foremost. The 3.6 inch, 720p screen doesn’t make for a great bullet point on the box, but it enables the small device size, and excellent battery life.
The device itself is well-built and demonstrates typical Astell&Kern quality in the small details. The buttons are tactile and responsive, the volume wheel is smooth with a small but satisfying click to the movement. The fit and finish is top notch, with clean edges and secure, solid feeling jacks. In terms of providing a premium, luxury feel in a DAP, Astell&Kern is second to none.
The package is fairly minimalist. The box itself is nice, and inside you’ll find the device, a charge cable, quick start guide, and screen protectors. Cases are available separately, and between the slightly odd angles of the device and the glass back, you’ll probably want a case to keep anything from getting scratched up.
Interface
Probably the most anticipated change to the SR35 is that it’s now the second device with A&K’s new “Crimson” UI, which was originally developed for the SP3000. Crimson updates the library management and player interface from the previous UI, which was several years old. Part of what made the SP3000 such a revelation was that it combined an improved UI with vastly improved performance. SR35 has the UI, and improved performance over previous models, but the difference in performance over previous models isn’t as vast.
SR35 continues Astell&Kern’s practice of providing downloads for select music players directly through the Services menu on the device. App load times and performance within apps is good. It doesn’t have the snappy, responsive feeling of the SP3000, but also rarely if ever feels sluggish. The screen size and orientation can create some challenges for those with larger hands and fingers. I’m honestly impressed with the accuracy of the keyboard in deciphering that I intended to press “S” instead of “A” or “D” 95% of the time.
So basically, SR35 is like a smaller, slower SP3000. Its size is a two-edged sword, making it much more genuinely portable and providing much more battery life than most other DAPs with anywhere near the same level of sound quality or function, but also creating some usability issues. The speed and performance is fine, but don’t expect an upgrade over the SR25 MKII on the same scale that the SP3000 improved on the SP2000.
Sound
SR35 continues its sense of being a scaled down SP3000 in its sound. On first listen, I found it to be remarkably similar in the character and overall tuning to SP3000. Same black background, and the same sort of tuning that takes a detailed, reference sound and adds a sprinkle of smoothness and a touch of relaxation for a sonic delivery that you could listen to for hours. SR35 is quintessential Astell&Kern brought down to a more accessible price point. Now is SR35 able to deliver the precision, intricate detail, resolution, and immersive imaging of SP3000? No, but that doesn’t stop it from trying.
The bass presentation aims for accuracy and linearity, with excellent texture. There isn’t much emphasis in the low end. The mids are likewise rich and natural, with a hint of warmth and excellent timbre. The treble is natural and well-extended. It’s slightly smooth, offering a vibrant, but non-fatiguing top end.
SR35’s imaging and soundstage benefit from the rock bottom noise floor and inky black background that Astell&Kern is famous for. It presents great width and three dimensionality to the stage, and holographic imaging delivery. With IEMs that have strong imaging characteristics like the U12t or Campfire Solaris Stellar Horizon, SR35 delivers a vivid, lifelike stereo image.
SR35 and PA10
SR35 is an excellent pairing for IEMs, and does well with easy to drive headphones like the Focal Celestee or Audio-Technica ATH-M70x, but it can struggle with planar magnetic headphones, and anything harder to drive. After listening with headphones like the Meze Liric and HIFIMAN Arya, I thought I’d try pairing it with the PA10, Astell&Kern’s recently released standalone portable amp. The two proved to be an excellent match.
With portable devices often the issue is that while a device can generate sufficient voltage, it can’t deliver enough current. Part of PA10’s charm is that it allows you to adjust the output voltage and current separately. This covers both cases of “hard to drive” headphones. With higher impedance headphones you can increase the voltage, and with lower sensitivity headphones you can increase the current.
Pairing SR35 with PA10 lets you go from being able to drive a handful of easier to drive headphones, to driving a wider range of harder to drive ones. Arya, LCD-X, and the DCA Aeon 2 Noire all felt great with PA10. Sonically, PA10 adds a bit of muscle to SR35’s sound, and widens the soundstage – even with the easier to drive headphones.
Of course, PA10 adds quite a bit of size to your setup, and removes the pocketability to some degree. However, if you’re looking for a sort of modular option that can provide massively portable pocketability for some cases, and a bit more power – at the cost of size – for other cases, SR35 + PA10 is a great solution.
Comparison iBasso DX240 and Astell&Kern KANN Max
For comparison, we brought in a couple DAPs that are a step above the SR35: iBasso DX240 and – a personal favorite of mine – Astell&Kern KANN Max. Each player has some unique characteristics that help it stand out from the other two, but there are also a number of similarities.
In the build and design, DX240 has the edge of having the biggest screen, but otherwise, the A&K units have clearly better materials and build quality. DX240 is slightly slimmer than KANN Max, but SR35 is the smallest by a good margin. In terms of usability, DX240 boasts the classic stock Android, but has some challenges in the setup due compatibility issues with some of the preinstalled software that requires the user to immediately update the firmware before they can install any apps. DX240 has the best system performance and responsiveness, but SR35 does very well and outperforms the KANN Max for virtually every task.
Sonically, the three exist on a spectrum of most-to-least neutral. DX240 provides the most incisive, reference sound of the three, with strong detail and a reference-like presentation. KANN Max has a similar sense of being highly accurate, but presents the sound with a more organic feeling, and a bit more weight and body to notes. SR35 has the most “color” to the sound of the three, with that slight warmth and somewhat relaxed feeling.
In terms of the technical aspects of the delivery, the three are very close. KANN Max has the best balance of resolution, detail retrieval, and natural delivery. DX240 has the detail and resolution, but can feel slightly grainy in the treble in comparison with the other two, and lacks the same sort of organic feeling. SR35 has the natural character of KANN Max, but doesn’t quite match it in detail and resolution.
The names might change, but the story remains largely the same: iBasso delivers great technical performance and a better UI (with some caveats here), while Astell&Kern provides a better build and a more unified user experience that lacks the flexibility of the iBasso devices. Considering that it’s $500 cheaper than the KANN Max and $150 less than the DX240, SR35 makes a strong case as a “bang for your buck” player that doesn’t feel or perform at all like a “budget” option.
The Bottom Line
Most people don’t know that $4000 portable digital audio players even exist. Among those who know, very few of us will even spend $1000 on a DAP, but we might be left wondering what we’re missing out on. If you want a taste of what a flagship player does, without dropping a mortgage payment or two on one, SR35 delivers a perfectly scaled down version of the SP3000 sound, bringing Astell&Kern’s flagship experience down to a level we can all enjoy.
