Integrated Amplifiers

Since I last tested Naim's evergreen Nait – the XS 2 in HFN Jun '14 – the most fundamental update must surely be the inclusion of a very capable MM phono stage. Retaining the ALPS volume control, reed relays and ceramic insulators for the power transistors, there seems very little change in the technical 'fingerprint' of the Nait. For example, the 2x83W/8ohm and 2x128W/4ohm power output of the XS 2 is mirrored in the 2x85W/8ohm and 2x130W/4ohm measured for the XS 3. Naim has tweaked the Nait's output protection, however, for while the XS 2 delivered 105W, 178W, 275W and 130W under dynamic conditions into 8, 4, 2 and 1ohm, the XS 3 offers an identical 86W/182W into 8/4ohm but mutes with any output above 130W/70W (8.4A) into 2/1ohm loads [see Graph 1, below]. Distortion remains fairly consistent at 0.004-0.009% through the midrange over the rated 1-70W, increasing to 0.035% at 20kHz.

Also unchanged, the overall gain is a little higher than average – higher than necessary to accommodate modern digital sources – at +44.5dB while the A-wtd S/N ratio is just slightly below average at 76dB (re. 0dBW), though it'll never be identified as conspicuously 'noisy'. As with other Naim amps, the output impedance is held high by series resistance to 0.24ohm and the response marginally rolled-off at –1dB/20kHz, continuing to fall away to –21dB/100kHz. While fans of high-rate DSD and 192kHz+ LPCM might baulk at this ostensibly curtailed response, in practice it is no bad thing. Moreover, in a one-brand system, the response will be determined by the 28kHz limit of Naim's DACs and streamers [see red trace, Graph 2, and HFN May '15, Nov '17, Sep '18, Jan '19 and Apr '19]. PM