Turntables, Arms & Cartridges

Most recently tested in HFN Jul '09 and Jan '11, comparisons between the last 'OC9s and this new 'OC9XSH are instructive. The headline change lies in the AT-OC9XSH's response or, more correctly, a difference in the left and right channel responses – the left flat to within tight ±0.5dB limits from 50Hz-15kHz while the right shows a lift through the treble of +1dB/9kHz to +2.2dB/13kHz [solid vs. dashed traces, Graph 1].

Similarly, while the latest PCOCC coils and neodymium magnets have boosted output from 400µV to 470µV (AT-OC9III vs. AT-OC9XSH, re. 1kHz/5cm/sec), and channel balance has improved from 0.5dB to 0.3dB, there's also been a shift in the symmetry of the generator: lateral cuts now have a 'brighter' sound than vertical [black vs. red traces, Graph 1]. Subjectively this brings central stereo images (solo voices) forward while peripheral images are pushed slightly backward. Distortion, however, is consistent between lateral/vertical cuts [Graph 2].

Mechanical compliance has been slightly relaxed to 23cu/30cu (vertical/lateral) – higher than A-T's rated 16cu – so the 'OC9XSH is better suited to low/medium effective mass arms. VTA has also been fettled back to an ideal 22o. Downforce is unchanged at 2g and the boron cantilever retained, but even with the one-down-from-top Shibata-equipped model we have here, its tracking performance has improved from 'excellent' to 'outstanding'. On test it sailed through the top 80µm band and suffered distortion of just 0.2% and 0.3% at 315Hz with the +15dB and +18dB test tracks, respectively (re. 5cm/sec). It's an MC boasting top class MM tracking performance! PM