Pre/Power Amplifiers

While there have been software/firmware updates between the Altair G2.1 [HFN Oct ’21] and this G2.2 iteration there have also been ‘tweaks’ to the analogue output stage that now runs at either a 2V (2.35V) or 6V (6.23V) output rather than the former’s 4.9V. This is sourced from a remarkably low 135mohm impedance that will not only drive ‘exotic’ interconnect/amplifier combinations but, with a suitable adapter, may also serve as an effective headphone amplifier. Auralic’s self-titled ‘Orfeo’ volume control and output stage is otherwise retained alongside ES9038 DACs, the combination maintaining a very consistent 0.0002-0.0005% distortion (20Hz-20kHz) over the top 30dB of its dynamic range [see Graph 1, below]. Digital jitter remains vanishingly low, with a correlated figure of <20psec across all sample rates and inputs, while the combination of a super-wide 119dB A-wtd S/N and resolution good to ±0.1dB over a 110dB dynamic range indicates a ~20-bit resolution for the Altair G2.2.

The G2.2 also includes ‘Clear’ and ‘Mellow’ tone modes which appeared as a ‘Beta’ release on the Lightning DS web interface but were not enabled here. The four familiar linear phase (Precise, Dynamic, Balance) and minimum phase (Smooth) filters are included, and looked to ‘load’ once selected, but were also inoperative, falling back to a default configuration. (The latest 10.0.3 firmware was installed.) Instead, all 44.1kHz-centric inputs were upsampled to 1.4112MHz and 48kHz-based streams upsampled to 1.536MHz via a very long-tap linear phase filter showing extensive pre/post ringing [see Graph 2] but offering an astonishing 135dB stopband rejection and flat responses out to –0.02dB/20kHz, –0.2dB/45kHz and –1.4dB/90kHz with 48kHz, 96kHz and 192kHz media, respectively. PM