Astell&Kern HC4

Hi-Fi Sound on the Move, AK HC4

Astell&Kern offers a Hi-Fi USB DAC cable product range for a true Hi-Fi experience on smartphones and PCs.

The Hi-Fi sound provided by Astell&Kern's design, which was completed in a small size, has won praise from countless audiophiles and media.

The AK HC4 continues the advantages of its highly acclaimed predecessors, delivering even more perfected sound in various usage scenarios through advanced design. Featuring Dual Output, compatible with most IEMs and headphones, the AK4493S DAC for true Hi-Fi sound, and Digital Audio Remaster technology, it brings the level of Hi-Fi sound previously exclusive to Astell&Kern's digital audio players to the AK HC4. Enjoy Hi-Fi sound like never before.

Selection for Hi-Fi Sound – ultra-high resolution sound from AKM AK4493s DAC

To achieve the highest audio quality achievable with a USB DAC, the AK HC4 is the first in the USB DAC Cable lineup to incorporate AKM's DAC. AKM's DAC has earned much love when featured in Astell&Kern's digital audio players, but due to the small size of USB DAC Cables and the challenges of amp design, it has been difficult to implement in the USB DAC Cable lineup until now.

The AK4493s DAC from AKM, used in the AK HC4, is further enhanced with improved noise control, lower power design, and ultra-precise amp design technology, delivering exceptionally high-quality Hi-Fi sound. Furthermore, it supports Native DSD256 and up to 32bit/384kHz to handle any high-quality audio source, allowing you to experience the high-grade sound quality that Astell&Kern delivers.

Precision DAC and AMP Design for Hi-Fi Sound

In order to gain stable output power and ultra-high-quality Hi-Fi sound through the Dual Output, AK HC4 introduces an exclusive AMP circuitry that supersedes the standard built-in DAC AMP.

While maintaining a compact form factor 29.5 x 64.5x 14.5mm, we used micro resistors and capacitor parts to achieve a small footprint without compromising performance. Carefully selected ultra-small tantalum capacitors, which are used in AK player products to create a stable system and audio performance by controlling the power fluctuations, are also included to create an optimal audio circuit design. In addition, the output and audio performance are enhanced with Astell&Kern's unique power management technology to minimize current consumption in respect of the connected device.

3.5mm, 4.4mm Dual Output 

The AK HC4 features Dual Output with both 3.5mm and 4.4mm connectors, allowing you to use AK HC4 with most Hi-Fi IEMs and headphones without the need for adapters or additional cables.

The 4.4mm Balanced output provides a high output of 3Vrms, maximizing the performance of sensitive headphones and IEMs, while ensuring clear channel separation and minimal noise.

The 3.5mm Unbalanced output is compatible with the majority of existing IEMs and headphones, offering a sufficient output of 2Vrms to fully experience the capabilities of your IEMs.

Digital Audio Remaster Technology for Even More Vivid Original Sound

The AK HC4 is equipped with digital audio remaster (DAR) technology, which was only applicable to the latest digital audio players from Astell&Kern.

DAR technology is developed to upsample the sample rate of the sound source being played to go beyond the limits of the source format.
The high sample rate allows more refined play and offers delicate and analog-like original sound, helping you to enjoy the richness of the original sound, subtle differences in the nuance of the music and rich sounds at a higher level.

In addition, the DAR slide key on the side of the product gives you a more intuitive selection of DAR options.

* The DAR function can be selected On/Off depending on the sound source or your preference.

* Supports PCM playback conversion Rate up to 384 kHz/DSD256.

DAR option: Maximum Conversion Rate

PCM:

44.1kHz range PCM will be converted to 352.8kHz for playback

48kHz range PCM will be converted to 384kHz for playback

No conversion will be made when playing DSD with this option selected

DSD:

DSD files below DSD256 will be upconverted to DSD256 for playback

High Compatibility and Simultaneous Support for UAC 1.0 & 2.0 for Gaming

While modern smartphones, tablets, and PCs support UAC 2.0 connections, many gaming devices still exclusively support UAC 1.0 connections.

To cater to both scenarios, AK HC4 ensures compatibility by supporting both UAC 2.0 and UAC 1.0 connections for cross-platform quality sound experiences.

Connect AK HC4 to your gaming device such as PlayStation and Switch, and enjoy low latency and enhanced sound for an immersive gaming experience.

Noise-Free Rear Output Structure

AK HC4 incorporates a rear audio output design to minimize noise.

Most USB DAC products have the DAC positioned in the USB terminal that is connected directly to the device to process and output audio.

However, with the HC4, digital signals from the device go through the dual shielded cable to the audio circuit before being converted to an analog signal by the DAC. By processing the digital signal after, the result is superior, noise-free sound compared to other USB DAC products.

Dual Noise Shielded Cable

To ensure optimal usability across both Android and iOS devices without the need for additional adapters, AK HC4 features an interchangeable cable that readily supports Type-C and Lightning connections. 

The AK HC4 features a dual shielded cable to minimize noise and deliver a more vivid, original sound.

The copper core wire is coated with tin to prevent corrosion and strengthen tensile force for enhanced durability.

Additionally, the entire cable is wrapped in an aluminum film to block noise with an extra layer of shielding around the power cable to further minimize noise, the biggest issue in audio, then the tin-coated copper wire is woven to minimize noise interference to sound.

Finished with a fabric jacket on top of the TPE jacket, the cable features enhanced durability and usability with perfect aesthetic appeal.

LED for real-time indication

AK HC4 has an LED indicator located on the front, that displays song details and USB Connection.

Standby : White  /  PCM : Red  /  DSD : Blue  /  UAC1.0 : Green 

* When connected to UAC 1.0, the LED is fixed green.

Standby : White  /  PCM : Red  /  DSD : Blue  /  UAC1.0 : Green 

* When connected to UAC 1.0, the LED is fixed green.

General Specifications

•  Model: AK HC4

•  Body Color: Moon Silver

•  DAC: AKM AK4493S 

•  Sample rate: PCM : 8kHz ~ 384kHz (8/16/24/32bits per Sample)

• DSD Native: DSD64(1bit 2.8MHz), Stereo / DSD128(1bit 5.6MHz), Stereo / DSD256(1bit 11.2MHz), Stereo

• Output Level: Unbalanced 2Vrms / Balanced 3Vrms (Condition No Load)

• Input: USB Type-C (Supports UAC 1.0 and UAC 2.0)

• Output: 3.5mm (Unbalanced), 4.4mm (Balanced, Only 5-pole supported)

• Dimensions: 29.5mm[W] x 64.5mm[H] x 14.5mm[D]

• Weight: About 1.09oz (31g)

Audio Specifications

Frequency Response

±±0.062dB (Condition : 20Hz~20kHz) Unbalanced │ ±0.063dB (Condition : 20Hz~20kHz) Balanced 

±0.066dB (Condition : 20Hz~70kHz) Unbalanced │ ±0.067dB (Condition : 20Hz~70kHz) Balanced 

Signal to Noise Ratio: 118dB @ 1kHz, Unbalanced │ 118dB @ 1kHz, Balanced

Crosstalk: -134dB @ 1kHz, Unbalanced │ -136dB @ 1kHz, Balanced

THD+N: 0.0005% @ 1kHz, Unbalanced │ 0.0009% @ 1kHz, Balanced

IMD SMPTE: 0.0005% 800Hz 10kHz (4:1) Unbalanced │ 0.0004% 800Hz 10kHz (4:1) Balanced

Output Impedance: Unbalanced Out 3.5mm (0.9ohm) │ Balanced Out 4.4mm(1.6ohm)