Astell & Kern AK240 Stainless Steel
Brand Astell & Kern
The unwavering strength of stainless steel.
At Astell&Kern, we study countless materials to remain faithful to our design philosophy:
Deliver the unique beauty and pure essence of the raw material intact without needless processing.
"A strong, non-corrosive metal that does not easily bend or damage."
"A metal that can restore damage through polishing."
This type of metal is already widely used on high-end timepieces.
Unlike the previous iterations that employed duralumin, the Astell&Kern AK240SS is constructed with stainless steel to take full advantage of its inherent benefits.
Due to the extremely difficult processing techniques and high costs when compared to aluminum, stainless steel is generally reserved to high-end timepieces.
We at Astell&Kern have created the most special version of the AK240 to date using stainless steel to bring you only the best.
Native DSD Support
What is DSD?
DSD (Direct Stream Digital) is a digital audio file format originally developed for SACDs (Super Audio CD).
Regular digital audio file formats such as PCM (Pulse Code Modulation) is separated into 65,000(16bit) to 16,700,000(24bit) of information on the Y axis, and 44,100(44.1kHz) to 192,000(192kHz) across the X axis for digital signals.
DSD files have 1bit (0s or 1s) for Y axis and is separated into 2,800,000(2.8MHz) to 5,600,000(5.6MHz) of information for X axis.
Compared to regular audio CDs with 16bit/44.1kHz PCM format, SACD’s recording frequency goes up to 100kH and the dynamic range goes beyond 120dB while maintaining sound clarity during the transmission.
Native DSD Support
One of the approaches we decided that would help us move a step closer to the original sound quality was to provide native DSD playback without having to convert it into PCM. This was indeed a difficult task. In order to provide native DSD playback on the AK240SS, we had to select a different DAC chipset.
Making the decision to change the DAC was not easy, but in order to reach our goal, we had to make a bold move which was to start from scratch.
We have asked ourselves: Does the DAC support Native DSD?
Will it allow for the Dual DAC setup? What else is needed for the perfect Native DSD support?
In order to answer these three questions, we have decided to use the Cirrus Logic CS4398 chip in the Dual DAC setup with an added exclusive XMOS chip that will allow for Native DSD support.
The process of setting up Native DSD support was not an easy task. Since the main CPU does not process Native DSD, we needed a chip that will work with it. It took us a long time, but we made it work. Through countless hours of testing, we were able to achieve Native DSD playback by having the main CPU process the data, send it to the exclusive XMOS chip, then through the DAC to deliver the sound.
Unbalanced vs. Balanced Output
The unbalanced method is the most commonly used basic method which consists of “left and right signals + ground line”.
This setup includes a ground line which blocks out external noises from the outside.
However, since the ground line cannot block out all of the external noises completely, external noises can be mixed into the signals that are transmitted, which then result in changes to the sound.
The longer the signals travel, the more external noises that will be mixed into the sound which is why it is used within a short distance of 1 to 2 meters.
Unlike the unbalanced method, the balanced method has an additional cold signal to compliment the hot signal which reduces the external noises.
Balanced Out and Dual DAC
Dual DAC meets Balanced Output
It did not take us long to figure out that the AK240SS’s Dual DAC and balanced output resulted in the best sound.
During the development of the AK100 and AK120, Astell&Kern's specific analogue amp setup was already creating full balanced analogue signals streaming from the DAC and we were able to move a step closer towards the original sound by then creating a balanced output terminal at the end.
256GB of Massive Storage
Astell&Kern has created the AK120 Titan with a storage capacity of 128GB, but in order to support Native DSD, MQS, and massive audio files, we had to come up with the ultimate portable music player with 256GB of storage.
With 256GB of internal memory, about 2,500 MQS (24bit/96kHz, 4 minute-long, 90MB) songs can be saved.
With the addition of a 128GB microSD card, the AK240SS can support up to a total memory capacity of 384GB.
Astell&Kern products have started to evolve into network players by providing Wi-Fi capability.
To listen to your favorite music, you no longer have to turn on your computer, search for your music, wait for the songs to download, connect your player via USB cable, and then wait for the files to transfer to the player.
Now with MQS Streaming, you can easily download or stream music directly from the AK240SS by having the unit and your computer connected to the same network.
- "Astell&Kern MQS Streaming Server" software must be installed on your PC or MAC with a shared folder saved for MQS Streaming to work.
/ DSD Native : DSD64 (1bit 2.8MHz), Stereo / DSD128 (1bit 5.6MHz), Stereo
/ ±0.3dB (Condition: 10Hz~70kHz) Unbalance & Balance