Naim’s Unitiserve comes with an inline switching supply but a linear power supply with a transformer such as is found in Naim’s HI-CAP helps enhance performance. Since this has not been made for the Unitiserve, Longdog Audio Naim Uniti Serve Power Supply PSU Upgrade is a 5A supply made for this purpose.
Using high current MOSFET transistors to accommodate the required 12 volts of DC at 4.8 amps, the unit incorporates doubling arrangement to create a suitable supply that doesn’t need heat sinking.
The Long Dog XLCR comes in a reasonably compact case around twice the height of the Unitiserve. It has a green LED on the front fairly brighter than contemporary Naim kits. On the back there’s an IEC mains, output via a short lead with 4-pin DIN at the supply end and an Oyaide DC plug for the server.
The change this power supply brings is remarkable, it adds vigour to dynamics, opening up the soundstage and revealing a surprising amount of detail by pushing the noise floor down to expose quieter sounds and fine details that combine to make reverb last longer and instruments and voices sound more real. With an improved ability to hear more, you can tell where each note stops and starts so timing is a natural benefactor. Essentially you hear what the server can do and less of the noise that the standard supply injects into the wall.