Streamers — SOtM sMS-200

The sMS-200 is the original mini network player from SOtM of South Korea, a small box that receives music over the home network and passes it on to an outboard DAC through USB. It has no converter, display or analogue outputs of its own. SOtM built it on a Media Player Board of its own design and later followed it with the sMS-200 Neo update and the sMS-200ultra, which carries an upgraded clock.

Key specs that matter

Playback reaches PCM at 32-bit and 768 kHz and DSD512, provided the connected DAC accepts those rates. Connections are a single audio-grade USB port for the DAC, two ordinary USB 2.0 ports for external drives and an RJ45 Gigabit Ethernet socket. The audio USB port supplies 5.0 V with over-current protection at 0.8 A, and SOtM advises keeping the load under 0.5 A. The unit runs from an external DC supply between 6.5 and 12 V and draws no more than 15 W. The case measures 106 x 48 x 152 mm and weighs 1.5 kg, and SOtM specifies an operating range of 10 to 30 degrees Celsius.

Engineering and use context

At the heart is an ARM processor board that SOtM developed for audio duty, with the extra functions of generic computer boards left out. Its circuitry draws on the same in-house parts SOtM uses in its tX-USB cards and SATA filters - a clock with very low jitter, low-noise voltage regulators and an active noise canceller. The operating system is Eunhasu, a Linux build stored on a micro SD card and controlled through a browser on a computer, phone or tablet. From that interface the owner switches between Roon Ready, a DLNA renderer, MPD, Logitech Media Server with Squeezelite, Shairport for AirPlay and an HQPlayer network audio adapter mode, and Librespot was added for Spotify. Music can come from USB storage, shared network folders or streaming services, and drives formatted as NTFS or FAT are read from firmware 0.2.7, one partition per drive. Early units shipped with 100 Mbps networking and were later brought up to Gigabit through a hardware and software upgrade. Firmware 0.3.0 enabled Wi-Fi through a USB dongle with the RTL8812AU chipset, and a Diretta driver is also offered.

Pairing

A converter with a USB input is all the player needs downstream, and SOtM names its own sHP-100 and sDP-1000EX as partners, with the tX-USBhubEX between player and converter. The maker asks for a Gigabit router and Ethernet cable of CAT6 grade or better, and lists one known clash with the USB 2.0 input of the Mytek Stereo192-DSD.

Alternatives

The SOtM sMS-500 is the newer network player that replaced the sMS-200 in the range, built on a quad-core processor board.