I will have to read the article, but Minerva has no USB port.
Indeed, you are correct - the Minerva has no USB. The improvement was reportedly made using an Empirical Offramp which would have fed the Minerva via SPDIF or I2S if it has that option. That was said to be superior to the Minerva fed by its native Firewire interface. The Offramp is a USB device.