I first heard an Astell & Kern player back in 2014 whilst auditioning a pair of headphones. I remember the dealer raving about it being so good that he had sold his CD player and replaced it with an Astell & Kern AK240, which from memory, was the player used for the demo. It was also my first experience listening to a hi-res file, which may have been the root cause of the considerable future shrinking of my bank account.
Astell & Kern is owned by the South Korean company Dreamus, who also own the consumer electronics company iRiver. Astell meaning ‘star’ in Greek, kern meaning ‘core’ in German, the company launched their first player in 2012, the AK100. Ten years later, they now have five ranges of DAP players, from the budget Activo, to the high-end Ultima, also headphones, a CD ripping drive and a variety of home audio equipment. I am sure I am not alone in finding the huge array of players from the brand rather confusing, but I think I’m right in saying the SP2000T reviewed here is the cheapest model in the highest tier Ultima range. I requested this model as I was intrigued by the tube output stage. Some ferreting around the internet revealed that this is not the first player to feature such an output stage, although A&K claim the SP2000T is the first DAP to feature a hybrid amp mode.
Build quality and design
The SP2000T is a lovely thing to behold. I feel the designers have done well to keep the weight down to a smidgeon over 300g considering the unit’s perceived build quality and features. The machined aluminium sides of the casing have stylish, sculptured edges and the volume control has a spiral design, specific to this model. The front is almost entirely taken up by a five inch, full HD screen, however, the clever bit is the design of the rear panel; covered in a single piece of glass with a frosted effect on the centre and lower part, the upper part acts as a display that shows the different amp modes or sample rates. The top houses the power button and three headphone outputs, including 3.5mm and both 4.4mm and 2.5mm balanced sockets, the latter I shall talk about later. The top left side has three buttons for track-skip forwards and back, plus pause. The top right side has just the volume control and along the base is a USB C port for both charging and file transfer, plus a micro SD slot.
It would probably be easier to talk about what it doesn’t have than trying to mention everything on offer, so I will concentrate on what’s important. At the heart of the DAC stage is a Quad-core ESS ES9068 which allows the SP2000T to play virtually any digital format, from lowly MP3, all the way up to DSD 512, DXD and MQA. Dual-band Wifi allows seamless connection to your home network and Bluetooth aptX HD is supported, although I did not test this. Up to 256GB of music can be stored in the internal memory, with micro SD cards up to 1TB taking care of those with larger appetites.
Unusually DAP users can transfer music to the SP2000T over a shared wireless network, via what A&K call File Drop. The OS system is Android-based and supports UPnP. The player allows various third-party apps, such as Tidal, Spotify, Amazon Music, Deezer and Qobuz to be installed and run natively. I only tested Qobuz and was pleasantly surprised to discover the player was able to download files for local playback. This facility proved especially useful for playing higher resolution files where Wifi was limited. These files are of course only accessible for as long as the user has a subscription but they sounded notably better than tracks streamed over Wifi. The player can connect to your router via either 2.4 or 5GHz connections, although there is no ethernet socket provided for wired access. As the owner of both the Chord Poly/Mojo and Chord 2Go/Hugo2, I initially missed being able to control music via my mobile phone. When I got around to actually reading the manual, I discovered Astell & Kern have this covered via their AK Connect app. In addition to the browsing functions within the app itself, I was able to run Bubble UPnP on my phone and stream music to the SP2000T via any cloud streaming service compatible with Bubble, in my case Qobuz, and anything stored on my home network. Users must ensure the AK Connect App is installed and running in order to control the SP2000T with a third party app. It is possible to input login details for a Tidal account within the AK Connect app, but not for any other cloud streaming service which seems strange, as Qobuz was installed on the SP2000T, yet it was not possible to access it via AK Connect. However, tracks can be selected from Qobuz via Bubble UPnP, if you don’t want to take the SP2000T out of your pocket.
The USP of the SP2000T is, of course, the tube output stage, courtesy of a KORG Nutube device. You can choose between the standard op amp stage, the tube amp stage and a hybrid amp stage — the latter offering five steps of configuration. Battery life is quoted as up to nine hours. It turned out to be somewhat less than this, although I did play a lot of hi-res files and some of the listening was via some fairly power-hungry headphones.
It took some time to work out how to extract the optimum performance from the SP2000T. Initial listening via Meze Liric headphones the detail and overall clarity of the SP2000T was impressive yet something was missing. Chord’s Mojo 2 provided a far more solid foundation for the music, with tighter and better-controlled bass. Switching to Hifiman Sundara headphones produced similar results. I was utterly perplexed as I was sure the SP2000T was capable of more. I popped in a 256 GB card, loaded with both CD rips and hi-res files and went out for a walk.
Listening via Cardas A8 Anniversary IEMs improved the balance considerably. Opeth’s Deliverance produced strong, clear bass lines, hard-hitting drums, strong dynamics, wide-open soundstage and a clean top end, with a good sense of attack. The Pink Opaque by The Cocteau Twins in 16/44.1 sounded sweet and detailed, with a fulsome bass. At this point it seemed that the Astell & Kern/Cardas combination provided better synergy than larger, less sensitive, planar magnetic phones. I decided to try out Obravo Cupid IEMs next. I bought the Cupids as a stop-gap whilst the Cardas IEMs were out of action in early 2020, but they never really gelled with the Mojo. Connecting the Obravos to the SP2000T via the 2.5mm balanced output proved something of a revelation. I was now enjoying a performance from the SP2000T which I had always suspected it capable of producing. Via the balanced output the SP2000T delivered a great sense of weight and fullness to the lower octaves of both piano and acoustic bass which helped reveal a decent sense of recorded acoustic. Peter Gabriel’s So (24/96 FLAC), which is known to sound rather harsh via some systems, now sounded full and balanced. Tony Levin’s bass playing on Hear That Voice Again, which sounded strangely slow and muted via the single-ended output, now sprang to life and propelled the track along. The Obravo Cupids tended to sound a little upfront and hard-edged when used with Chord DACs but the SP2000T’s sweeter balance, especially with hybrid mode output selected, tamed this aspect and caused me to view these IEMs in a new light.
I decided to try some more sensitive PSB M4U1 headphones via the SP2000T’s 3.5mm single ended output although I haven’t used them since I bought the HiFiman Sundaras. Radio Activity, the first track on John Mclaughlin’s The Montreaux Years (Qobuz 24/44.1), provides a great workout for both speaker and headphone systems. Sounding rather underwhelming with the SP2000T’s single-ended output feeding more power-hungry planar magnetic headphones, the track came alive via the PSB M4U1s and I was able to ,make a direct comparison with the Chord Poly/Mojo and 2Go/Hugo2.
Using my Sundaras, the SP2000T outperformed the admittedly much cheaper and older Chord Poly/Mojo combination, sounding more dynamic, with fuller, more natural bass and a more expansive soundstage. Comparing it with the 2Go/Hugo2 was fascinating. The SP2000T sounded sweeter and more open with a greater sense of acoustic. The 2Go/Hugo2 being dryer, but more dramatic and dynamic, with perhaps a better sense of timing. Considering the price difference between the two machines, it was a surprisingly close call and more about personal preference than an absolute winner.
After a disastrous attempt to source a balanced cable for my Sundaras via a popular online seller, I had great success with a cable from Ebay seller jack-james-knight. Despite the very reasonable cost, this cable proved excellent. The SP2000T was more than up to driving the Sundaras via the balanced output. Sticking with John Mclaughlin the soundstage opened up in terms of both depth and width. So natural, yet engaging, was the performance, it almost felt like rolling back the years and listening to the musicians live. The missing weight and bass drive experienced via the single-ended cable were now in the past. Instead it produced a great sense of acoustic and very fast and natural-sounding bass.
Comparisons between the SP2000T’s three output stages were equally fascinating. The op amp sounds dryer, faster with a better rendering of fine detail and studio effects. This became the preferred option with electronic and dance music, especially when using Cardas A8 IEMs. The hybrid amp generally sounds fuller and more spacious and was often more enjoyable with rock and jazz while the full tube amp was generally not to my taste, sounding a little slow, small and dynamically constrained. That’s not to say it won’t suit some headphone combinations for some listeners, but not for me, at least not via the headphones used.
I very much enjoyed my time with the SP2000T. Whilst the single-ended output worked very well with my more sensitive full size headphones and IEMs, the balanced output delivered the SP2000T’s delights via less sensitive transducers. The ergonomics worked well, the screen is sensitive, fast reacting and produces a vibrant image. The build quality is flawless and exudes quality. The AK Connect app worked well, allowing easy music browsing on the network. Most of all, I enjoyed the vibrant, spacious musical performance, which proved non-fatiguing yet always engaging, as long as I used the output that best suited the chosen headphones. The SP2000T is an essential audition for any audiophile seeking a DAP at this price point.