It lives in a box styled similarly to the server and on any rational assessment definitely qualifies as a purist audio component. Changes made since we originally looked at this amp are to output distortion residuals which are now more firmly biased into low (primarily second-order) harmonics.

The amplifier features five inputs with record and preamp outputs and has an optional MM/MC phono stage. Both components are exceptionally well built and internally well endowed, and they're both unusually smooth in operation.

Adept audio

Unable to test the iPod's functionality with the Music Player for this review, we used a Sony MP3 player instead. As already stated above, it's not directly supported by the Music Player control system, but is compatible as an audio source via the USB 2.0 input and via this connection, it works extremely well.

More centrally to any rounded assessment of the server, CD ripping and internet radio are not directly dependent on the Music Player, they are clients that talk to the Music Player across a network and to a large extent are under the user's control using the client software. But it was clear from our experience with the test equipment that these elements are well designed, with key benefits over the common alternatives, for example in the area of jitter reduction using the online music database.

Once we'd acclimatised to the internet radio and the discs stored on the hard discs, they were fairly easy to access and use. But in the long term, the usability of the Music Player is compromised by the lack of a graphical interface, which is currently promised for the future.

Many will not be completely satisfied by the ergonomics of the server until this add-on becomes available. But, within the limits set by the front panel dot-matrix display and the simple control system, the designers have gone a great job. The supplied remote control gives fine grain access to the full feature set, but it is messily implemented and again highlights the need for a better solution.

Upgraded Power Plant

As already noted, we've looked at the amplifier before, but it was obvious that the Power Plant has changed, and for the better. Initially, we were surprised by its palpably smoother and more expressive quality. It no longer sounds obviously digital or mechanical in origin, a charge that was easily levelled at the earlier version.

It is now a more organic, fluid performer, that no longer sounds under stress through louder passages. In fact, it no longer sounds obviously like a digital amplifier, which is a valid criticism of the majority of class D amplifiers. If anything the sound is slightly soft-edged, which is not only unexpected, but gives the amplifier a far more analogue-like feel. The power stages produce considerable heft and authority, without sounding either hard or aggressive and have a truly organic way of tracking recorded dynamics.

The internet radio is dependent on the data rate currently in use and, of course, you don't have control over this, but the better stations with higher data rates – 192khz or better – worked better than we have heard internet radio perform in the past, but the reason appears to be better performance at the internet end of the hardware/software chain, rather than the Music Player itself.

The tools available for selecting and memorising stations are easy to access and do a good job. Lower data rate stations had a character that was very iPod-like, in other words scrawny and one-dimensional. The senior sources in the package, FM radio, the internal CD player and streaming from the users own discs, that have been ripped and stored on the users computer are the serious contenders here, of course. In fact, the internal CD player is extremely good and the FM tuner also performed well.