Прочие устройства — SOtM tX-USBultra

The tX-USBultra is a two-port USB regenerator and jitter cleaner from SOtM, a Korean firm that also builds network players, music servers and clock modules. It combines a USB 2.0 hub with the company's sCLK-EX12 clock board in a small case and is placed between a computer or music server and a USB DAC or digital-to-digital converter. It costs USD 1,100, or USD 1,300 with the master clock input option.

Key specs that matter

The input is a USB 2.0 Type B connector and the two outputs are Type A USB 2.0 ports, each with its own switch for the 5 V bus supply. The hub controller is USB 2.0 compliant and handles high speed at 480 Mbps, full speed at 12 Mbps and low speed at 1.5 Mbps. Output ports supply 5.0 V (+0.5 V, -0.25 V), with over-current protection at 0.8 A at 20 degrees C and a recommended load of up to 0.5 A. The standard power input takes 6.5 to 9 V DC at up to 2 A through a 5.5 mm OD, 2.1 mm ID jack, and a 9 to 12 V version can be ordered for owners whose supply delivers more than 9 V. The case is 106 x 48 x 227 mm and weighs 1.5 kg. Operating temperature is 10 to 30 degrees C, storage 0 to 40 degrees C, and humidity 10 to 90%.

Engineering and use context

The USB data stream is regenerated with timing from the sCLK-EX12 board, which uses a custom ultra low phase noise oscillator circuit and an isolated differential clock signal path. Five custom ultra low noise regulators and one standard regulator feed the circuits, backed by an active noise canceller. An optional 50 ohm BNC input accepts a 10 MHz master clock, and this connector is fitted only when that option is ordered. The unit is recognised automatically without driver installation, and a green LED bar confirms power. SOtM advises using only one of the two output ports at a time rather than both together. The box contains the unit and its operating instructions only, so a separate DC supply has to be provided, and the factory warranty runs for 1 year.

Pairing

A USB DAC that draws bus power from its host needs the switch of its port set to on, while a self-powered DAC can have the bus power line switched off. The same case width is used by the sMS-200ultra network player, which makes a matching two-box source when the player's USB output feeds the regenerator.

Alternatives

SOtM's tX-USBhub is a two-port audio USB 2.0 hub made in an internal version for PC cases and an external standalone version.