Astell&Kern A&ultima SP2000T DAP Music Player Review

Astell&Kern Meets the Tube

Tube, right? That's what the "T" stands for?

Astell&Kern will say not quite. It doesn't stand for just one thing. But yeah - of course it stands for tube.

Astell&Kern just won't. Stop. Innovating. Don't try to hold them back, because I'm still waiting for them to make a DAP with a built-in game console. It's just a matter of time, right? The introduction of the tube in a digital audio player isn't new, - iBasso has been doing it for years with replaceable amp cards. But if you've been paying attention Astell&Kern has been on a particular mission lately: and that is to give the listener options for how they want to listen to their music.

It started with the SE200, then the SE180, and now the SP2000T. So just how tubular is the new DAP? Let's find out.

Riff Notes Logo


  • Triple Amp System is a great way to customize your sound
  • Build Quality
  • Tube sounds great


  • Isn't quite on par with the SP2000 it's named after
  • Heat from the tube is not cause for alarm

Materials & Quality

Aesthetically this might be one of my favorite looking Astell&Kern players. It's the same excellent build quality as other AK DAPs, with the modern, angular design and sharp lines. Similarly, there are three buttons on the left side of the device, from top to bottom: back, play/pause, and forward. On the bottom of the device you'll find the USB-C charging port and the microSD card slot. The right side of the DAP you'll find the large volume knob that is quintessential of Astell&Kern styling. The engineering and smooth scrolling wheel is always one of the best parts of the AK experience. They just get it right every single time. On the top of the player you'll find (from left to right): 3.5mm, 4.4mm, 2.5mm headphone jacks, and the power button. All these design elements are consistent with other players in Astell&Kern's music player lineup. But that's about where the similarities stop.

The back of typical Astell&Kern players come designed with a glass back panel, but the SP2000T only has the top section (first quarter of the back) paneled with a glossy glass. Inlaid under the glass is also a colored LED indicating the bit/sample rate of the music you are currently listening to. In previous models this LED has been engineered as a ring around the volume knob, but the LED strip in the back is a nice new touch. Under the glass it looks a bit hazy, and at times I was wondering at what point would it reach full sentience and start selecting songs for me (it never did by the way). The rest of the back panel is a frosted grey glass with glossy lettering for the product information.

The engineering on any Astell&Kern DAP music player is going to be phenomenal, and the SP2000T is no exception. It's interesting to note that the SP2000T is lighter than the SP2000, mostly in part because of the new tube design in the circuitry that we'll delve into more in depth in the Features section. Because of this, you'll feel the DAP get warm during audio playback - this is completely normal - due to the tube inside. Usually in most electronics manufacturers will implement a fan for heat dissipation, but my guess is that because of Astell&Kern's material choice, the chassis of the player actually acts as a natural heat sink, by the aluminum absorbing and spreading the heat across its surface and allowing airflow to dissipate any remaining heat. Never did I think the device was getting hot enough to cause me to fear the electronics inside would get damaged.

Long story short: don't expect anything different here than the same excellent build quality Astell&Kern is known for.

Sound Quality

If you haven't figured it out by now, what sets the SP2000T apart is the fact that it is equipped with a portable-friendly dual-triode KORG Nutube. The Nutube is good for about 30,000 hours, and features an anode grid filament structure which operates the same as a triode vacuum tube. It's much smaller, consumes less power, and still delivers the same audio with rich overtones. Astell&Kern also utilizes an ES9068AS quad-DAC in the SP2000T, allowing 2 DACs per channel. The pairing of the ESS chip with the tube is a deadly combo, allowing the 2000T to have a sound signature that differs from the SP2000 flagship enough to make it unique to the device.

Say what you will about Don Henley, but The Boys of Summer is a solid hit. Listening to the SP2000T through the OP Amp Mode is what you would expect from AK - amazing detail and crispness. Those who prefer warmth will find the low end balanced, but lacking in depth to fill out those low frequencies. Tube Amp Mode is a different story however, adding a nice bloom to the music, that warmth extending even to the small tambourine in the intro, rolling off the transients and harshness of the metal to a more natural and organic sound. Bass is integral to yacht rock and 80's pop hits - creating a smooth timbre which sets the atmosphere for an inviting and pleasant listening experience. Henley's voice retains the smoothness on the higher notes under the control of the KORG Nutube, whereas it can sound thin under other ESS chips or the OP Amp Mode. It makes enough of a difference that it takes what I don't like about the song and filters them out enough to the point where it doesn't bother me. But again, what a hit, right?

One of the hottest albums for me right now is Brandi Carlile's In These Silent Days. She is a beast of a vocalist and song writer, and her new album is running on all cylinders. The song You and Me on the Rock is a great blend of Folk, Americana, and Pop, and it's just a great feel-good song. The acoustic guitar is featured prominently in this song, and it's interesting to hear how the left and right-panned acoustics are mixed differently. The right-side is more the rhythm guitar with some great percussive strumming, and as such is EQ'd much shallower than the left guitar which features more picking and lead lines. The picking guitar has much more low end and weight to it, bringing out the expressiveness of the performance. I like picking up on these subtleties, as they give me insight into my own mixing practices, but also how a device with multiple tonal options can affect the sound of individual performances of a song. The OP Amp mode brings out more of the attack on the picking, sounding precise and hearing more of the plastic of the pick hitting the strings. On the other side the Tube Amp Mode brings out the tail and body of the picked note more, rolling off the attack and presenting a more expressive performance.

Everyone loves a good epic soundtrack, and Thomas Bergersen (from Two Steps to Hell fame) delivers such epic soundtracks. The song Beautiful People from his collection Humanity Vol 1. is an emotional piece that shows off a lot of different elements from picking guitar, rock drums, flowing string sections, choral features, and of course epic and loud brass. There's a lot to uncover here, but the SP2000T handles it well. The beginning of the song is delicate, but like the Brandi Carlile number, the picking acoustic guitar again has much more weight and emotion when the DAP is in Tube Amp Mode. I actually prefer listening to expansive music like this in OP Amp Mode however, due to the size of the ensemble and overall dynamics, it's easier to use that detail and clarity to separate the different sections to my ear. The more musical and warm the sound is for very large and busy music the more muddled it sounds to my listening preferences. But that's the beauty of the SP2000T is that you can adjust the warmth and clarity to your liking. The loudest part of Beautiful People has epic drums and orchestra, full choir, rock drums, and more going on; there's a lot of competing frequencies but the power comes from the drums and drum set, plus the crescendoing of the brass section for the fanfares. Tube amp mode brings out that power in the low end and mids, but I find I lose some in the higher frequencies. Just the opposite with the Op Amp Mode, but the detail still allows for the various sections to be balanced and present in the mix. So this would be a perfect scenario to use the Hybrid amp mode to find that sweet spot between warmth and detail.

It's a trade off at the end of the day with sound and preference. What I truly appreciate is Astell&Kern understanding that everyone hears differently. And I feel like their product models of late mimic this exact sentiment. Why create a product with a certain (excellent) sound that will appeal to some and not others in an already polarized community? Options are good - and the SP2000T provides some of the best sounding options for a DAP in Astell&Kern's product line. But does it come at a cost? Are any sacrifices made? We'll discuss this more in the comparisons section coming up.

Don Henley Album Cover
Brandi Carlile Album Cover
Thomas Bergersen Album Cover
Betting for Benson Album Cover


The Boys of Summer by Don Henley

You and Me on the Rock by Brandi Carlile

Beautiful People by Thomas Bergersen

Places by Betting for Benson



The SP2000T is equipped with a portable-friendly dual-triode KORG Nutube, which is good for about 30,000 of continuous playback time. It features an anode grid filament structure which operates the same as vacuum tube, but is much smaller, consumes less power, but delivers the same audio with rich overtones.

The DAP is also designed in a way to minimize interference and noise from the tube. Astell&Kern utilizes magnetic forces to float the amp in the air, separating it from other mechanical parts, thus reducing the noise that is generated when contact is made or vibrations occur. Now, being that this is a portable music player, vibrations and movement are likely going to occur, so Astell&Kern's design is even furthermore beefed up with the application of shield cans and silver plating to eliminate noise and electromagnetic interference for superb audio performance.

Floating Tube Design

Floating Tube Design

Shield and Plating

Shield and Plating

Triple Amp System

Astell&Kern uses what they call the Triple Amp System on the SP2000T, using 3 modes to help you tailor your sound to your personal listening preferences. Three modes: OP Amp Mode gives you that classic AK signature – extreme clarity and dynamic sound. Tube Amp Mode gives you full access to the Korg Nutube with a uniquely warm and musical sound. Hybrid Amp Mode gives you control of just how much warmth or clarity you want – with 5 options to find just the right spot for you.

Quality of Life Improvements

The SP2000T comes with a Full HD 5-inch display (441 ppi), which is incredibly sharp and responsive. The larger touchscreen size and resolution makes the text clearer to read, album art vibrant and stunning, and includes more information on the screen than before. Replay gain, dual-band Wi-Fi (2.4 and 5GHz), AK File Drop, BT Sync, and a navigation revamp make for a smooth and intuitive user experience.


So how does the SP2000T compare to other DAPs, especially the flagship SP2000 music player?

The SE200 marked the first time Astell&Kern created a product giving the user option in how to listen to their music. It was also the first DAP on the market to include not one, not two, but three DACs in one music player. They utilized this in two separate channels: one using a dual-ESS DAC chip configuration and the other utilizing a single AK DAC chip for a warmer sound. It's still a great option for those wanting two very different sounding DACs in one device, but where the SP2000T ups the ante is with the ability to mix these signatures (from detailed to warm) for a custom listening experience.

The SE180 on the other hand took a different approach with the ability to completely swap out the input and DAC sections of the DAP, using modules that are completely cut off from the amplifier circuit. This allows the user to acquire specific DACs for sound options as well as offer varying headphone inputs for desired connections. Astell&Kern is continuing to develop their SEM modules for the SE180, so stay tuned for the latest information right here. Like the SE200, the SE180 still gives you options for either an ESS or AK DAC chip sound, but keeps the compatibility in one device so you don't have to buy a new device for a new sound. The added value here compared to the SP2000T again is still the customization of blending these detailed and warm signatures for a unique and personal sound, but the tube adds a touch of vintage to the mix as well. Tube circuitry just sounds differently than solid state, so if you're a fan of the tube sound (and not everyone is), then the SP2000T introduces the first tube circuit in an AK player, and should be a serious consideration.

The flagship SP2000 DAP music player continues to be the star of the show when it comes to Astell&Kern music players. Even though it was released over two years ago, the SP2000 is still the DAP to beat. It's equipped with dual AK4499EQ DACs - some of the best chips on the market, is able to output up to 6Vrms (balanced), 32bit/768kHz, 512GB internal storage, MQA, Roon Ready, and more. Sonically, the SP2000T sounds a lot alike the SP2000 when in full Tube Amp Mode, but the SP2000 still retains a lot of the clarity and transparency that the SP2000T loses with the tube. The SP2000's AK chips are vastly superior, and although the sound signature isn't completely determined by the DAC, the SP2000 still reigns as their TOTL (top of the line) music player.

Dragon Cable Experience

Due to the nature of the SP2000T and the variation of amp modes and filters it contains, the best choice for a Dragon Cable could go either way. For my testing purposes, I chose the Silver Dragon Premium Headphone cable to pair best with the SP2000T, only because I can regain some of the clarity and detail from my audio while getting the full benefit of the Tube Amp mode. If course, it wholly depends on your headphones and the genre of music you like to listen to. Feel free to Contact Us and we'll be more than happy to make a personalized cable recommendation just for you.

Silver Dragon Sound Signature

The Silver Dragon is the original cable. Silver strands clarify instrument separation, increase soundstage, and find previously lost high and mid-frequency sounds. Transients appear more cohesive and the bass tighter for a more controlled sound. The detail and clarity of the Silver Dragon make it a perfect match for classical music and other genres with many nuanced instruments.

For more information on finding your signature sound, visit our Sound Signature Guide.


It's hard to keep Astell&Kern from innovating for every new product they come out with. They've done it again, and the introduction of the new tube and triple amp system is yet another flavor for the audiophile who wants options. I'll say it again, creating a device that should appeal to more customers isn't a bad thing, even if some sacrifices are made that don't make it on par with the flagship player it is named after. It's new, it's innovative, and it's intended to bridge detail freaks and bass heads alike under one music player.

Does the SP2000T make the flagship SP2000 obsolete? No. But it does give the listener more options than the SP2000 to find the right sound for their music. The quality-of-life improvements also make the overall user experience more efficient and enjoyable. The SP2000T is a great option for those who want the option to adjust their music between warmth and clarity – and it sounds especially great for Classical, Jazz, Folk, and even EDM and Pop for music lovers who want a good thump in their ears. The vintage sound from the tube isn’t for everyone, but Astell&Kern gives you 7 options to find the right balance, making the SP2000T a great DAP for everyone.

Featured Products

Sold out

Sold out

Sold out

Sold out

What's in the Box

What's Included:

  • A&ultima SP2000T Device x 1
  • Leather Case x 1
    • SP2000T Onyx Black: Tan Case
    • SP2000T Copper Nickel: Green Case
  • USB Type-C Cable x 1
  • Quick Start Guide x 1
  • Warranty Card x 1
  • microSD card slot cover x 2
  • Protective Film (Front x 2, Back x 2)


Open Box Video (Coming Soon)

Review Video


Technical Features
  • Model: SP2000T
  • Body Color: Onyx Black
  • Body Material: Aluminum

General Specifications

  • Display: 5" FHD 1280 x 1080 Touch display
  • Supported Audio Formats: WAV, FLAC, WMA, MP3, OGG, APE, AAC, ALAC, AIFF, DFF, DSF
  • Sample Rate: PCM: 8kHz ~ 384kHz (8/16/24/32bits per Sample) / DSD Native: DSD(1bit 2.8MHz), Stereo / DSD128(1bit 5.6MHz), Stereo / DSD256(1bit 11.2MHz), Stereo / DSD(1bit 22.4MHz), Stereo
  • Output Level: Unbalanced 3.9rms / Balanced 6.0Vrms (Condition No Load)
  • CPU: Octa-Core
  • DAC: ESS ES9068AS x4 (Quad-DAC)
  • Vacuum Tube: KORG Nutube 6P1
  • Decoding: Support up to 32bit / 384Hz Bit-to-Bit Playback
  • Input: USB Type-C input (for charging & PC & MAC)
  • Output Level: Unbalanced Out (3.5mm) / Optical Out (3.5mm) / Balanced Out (2.5mm, only 4-pole supported / 4.4m, only 5-pole supported)
  • Wi-Fi: 802.11 a/b/g/n/ac (2.4/5GHz)
  • Dimensions: 3.07 "(78.1 mm) [W] x 5.55 "(141.1 mm) [H] x 0.68 "(17.5 mm) [D]
  • Weight: about 10.89 oz (309g)
  • Feature Enhancements: Firmware upgrades supported (OTA)


  • Supported OS: Windows 7,8,10 (32/64bit), MAC OS X 10.7 and up
Audio Performance
  • Frequency Response: ±0.024dB (Condition: 20Hz ~ 20kHz) Unbalanced / ±0.038dB (Condition: 20Hz ~ 20kHz) Balanced
  • ±0.027dB (Condition: 20Hz ~ 70kHz) Unbalanced / ±0.052dB (Condition: 20Hz ~ 70kHz) Balanced
  • Signal to Noise Ratio: 121dB @ 1kHz, Unbalanced / 123dB @1kHz, Balanced
  • Crosstalk: -137db @ 1kHz, Unbalanced / -142dB @1kHz, Balanced
  • THD+N: 0.0003% @ 1kHz, Unbalanced / 0.0003% @ 1kHz, Balanced
  • IMD SMPTE: 0.0003% 8000Hz 10kHz(4:1) Unbalanced & Balanced
  • Output Impedance: Unbalanced Out 3.5mm (1.5 ohm) / Balanced out 2.5mm (1ohm)

Clock Source

  • Clock Jitter: 25ps(Typ)
  • Reference Clock Jitter: 70ps


  • Capacity: 4,200mAh 3.8V Li-Polymer Battery
  • Playback Time: About 9 hours (Standard : FLAC, 16bit/44.1kHz, Unbalance, Volume 50, LCD Off, LED On, OP AMP Mode)
  • Charge Time: About 3.5 hours (Standard - 9V/1.6A Fast charging)
  • About 5 hours (Standard - 5V/2A General charging)


  • Built-in Memory: 256GB [NAND]
  • External Memory: microSD (Max. 1TB) x1

What To Read Next