Let's start with the hardware of "SXFI AMP". The size is about 17.5 x 67 x 9.7 mm (width x height x depth). Small enough to fit comfortably in the palm of your hand. It seems that it is well organized to this size. It weighs about 15g and is very light.
There are four simple buttons on the surface: a button to switch SXFI on / off (on in green), a volume up button, a play / pause button, and a volume down button. Connect to your PC or PS4 and smartphone from the USB Type-C connector. Headphones are used by connecting to the 3.5mm jack on the opposite side.
Currently, only Android 7.0 or later USB On-the G0 compatible smartphones can be used, and some smartphones such as Huawei Honor 9 Lite are not supported, and iPhone is not currently supported.
The DAC used in the "SXFI AMP" is the "AK4377" manufactured by Asahi Kasei Electronics. In terms of specifications, it is a chip with the ability to support PCM up to 768kHz and DSD256 (11.2MHz). "SXFI AMP" is capable of 24-bit, 96kHz playback.
To experience SXFI, you need headphones that support it. You can check the list of headphones from the PC software "SXFI Control" or the Android smartphone app "SXFI App". If you select and set either, the information will be saved in "SXFI AMP".
From the left, SXFI on / off button, volume up button, play / pause button, volume down button. When SXFI is turned on, the green LED lights up. A 3.5mm jack is provided at the top of the main unit, and a USB Type-C port is provided at the bottom. You can refer to compatible headphones with the PC software "SXFI Control". Android app "SXFI App"