Sony PS-X800 Turntable Lab Report

Lab Report

Sony's quartz-locked brushless/slotless direct-drive motor brings the alloy platter up to 33.3rpm in a little over one second and holds it to an absolute speed accuracy of +0.005%. Peak wow is very low at 0.02% [main signal, Graph 1] and while there's some slight broadening of the 3150Hz signal the peak-wtd flutter – with discrete sidebands at ±9Hz, ±18Hz, etc – is just 0.05%. Not only is the PS-X800 very pitch-stable but it is quiet too with a through-bearing/motor rumble of just –69.0dB (DIN-B wtd), reducing still further to –72.0dB (re. 1kHz/5cm/sec) when measured through-the-groove. Clearly, the combination of diecast alloy platter and rubber mat is effective in further reducing any motor-borne noise in the PS-X800.

The 'Biotracer' arm, meanwhile, has a pivot/stylus length of 180mm although the stubby square-section tube is just 80mm (3.2in) in length, hence the higher-than-average 165Hz main bending resonance [see CSD waterfall, Graph 2]. The limited harmonic and headshell flexing modes at 255Hz and 475Hz are further indications of the simplicity of a structure that hides relatively complex, miniature electromechanical engineering within. The latter is effective in applying downforce, albeit 10% light (so a setting of 2g yields 1.8g), and without the incremental 20Hz-80Hz 'bump/thump' we saw with the Technics SL-10 [HFN Apr '19]. Instead, the impact of Sony's 'continuous' adjustment of arm position may well explain the progressive increase in unwtd rumble from 20Hz down to near-DC. This lies below the –60.0dB hum and noise (unweighted), and also outside the DIN-B rumble weighting, but could it explain our reviewer's subjective bass experience...? PM

822vins.lab1

Wow and flutter re. 3150Hz tone at 5cm/sec (plotted ±150Hz, 5Hz per minor division)

822vins.lab2

Cumulative tonearm resonant decay spectrum, illustrating various bearing, pillar and 'tube' vibration modes spanning 100Hz-10kHz over 40msec

Turntable speed error at 33.33rpm 33.33rpm (+0.005%)
Time to audible stabilisation 1-2sec
Peak Wow/Flutter 0.02% / 0.05%
Rumble (silent groove, DIN B wtd) –72.0dB
Rumble (through bearing, DIN B wtd) –69.0dB
Hum & Noise (unwtd, rel. to 5cm/sec) –60.0dB
Power Consumption 17-36W
Dimensions (WHD) / Weight 440x120x445mm / 11.6kg
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