NAD D 1050

摘要

This may be part of a very new and fresh product range and enjoy the benefits of the popular XMOS-based USB audio input but, at its heart, the D 1050 is actually based on a decade-old DAC - the stalwart CS4398 from Cirrus Logic. This chip includes DSD processing and both fast and slow interpolation filters, the latter employed by NAD to minimise pre-echo in the time domain at the expense of a more protracted post-echo and a slightly reduced stopband attenuation of 78dB (subjectively, this is often preferred). The frequency responses remain very extended, out to within ±0.1 dB/20Hz-20kHz (44.1/48kHz files), -0.9dB/45kHz (96kHz files) and -6.6dB/90kHz (192kHz media) through both USB and S/PDIF inputs. With two exceptions, there's little practical difference between its USB and S/PDIF performance. The latter has a minute edge in low-level linearity (±0.1 dB versus ±0.2dB over a 100dB range) but the USB input offers a significantly 'cleaner' jitter spectrum down from ～300psec to just 12psec here [see Graph 2, below]. Its balanced XLR outputs offer a full 4.6V and wide 115dB S/N ratio from a moderate 90ohm source impedance which all suggest the D1050 will drive high-end preamps in style. Distortion is a low 0.0001-0.0006% over the top 30dB of its dynamic range at all frequencies [see Graph 1, below] and channel separation is a massive 130dB through the midrange.