Network Audio Players/Servers

Since our review of Matrix Audio's X-Sabre Pro [HFN Nov '17] the company has improved its ES9038 Pro/32-bit Sabre DAC-based platform still further. Most notably the 'untidy' 200psec jitter revealed in my lab report for the X-Sabre Pro has now been fully resolved – the Element X incurs just 5psec/48kHz and 55psec/96kHz, the latter a very low-rate ±6Hz pattern. Distortion is spectacularly low at 0.00003-0.0002% at the maximum 4.3V balanced output (20Hz-20kHz), holding to a mere 0.00015-0.00027% over the top 30dB of its dynamic range [Graph 1, below], while the A-wtd S/N is a class-leading 116dB via all digital inputs and resolution true to ±0.05dB over 100dB and ±0.2dB over a 110dB range.

The frequency response(s) depend on which digital filter is chosen [see Graph 2, below] while the negative-going time/impulse responses show the Element X is phase inverting. Filters 1 (Minimum Phase/Fast), 3 (Linear Phase/Fast), 5 (Brickwall), 6 (Hybrid) and 7 (Apodising) all have sharp roll-offs, with Filters 2 (Minimum Phase/Slow) and 4 (Linear Phase/Slow) offering gentler treble roll-offs, reduced 'ringing' but poorer stopband rejection. Otherwise, Filters 1, 3, 5-7 offer a similar 73-83dB rejection of digital aliasing images with 48kHz media, but just 18dB/14dB with Filters 2 and 4 which are better suited to higher sample rates. With CD/48kHz files the responses reach out to –0.1dB, –5.0dB, –0.1dB, –3.5dB, –4.0dB, –12.3dB and –0.8dB/20kHz (Filters 1-7, respectively). With 96kHz media, the 45kHz response limits are –0.09dB, –7.0dB, –0.4dB, –4.9dB, –14dB, –23dB and –7.5dB while, with 192kHz files, the 90kHz response limits are +0.2dB, –6.9dB, –0.3dB, –4.8dB, –14dB, –23dB and –7.3dB. PM