Turntables, Arms & Cartridges

As with SME’s other ‘MK2’ decks, the 4.6kg platter, 19mm sintered bearing and tower suspension of this latest Model 15 are informed by the original model, while the AC motor and two-box PSU/speed controller [see boxout, p51] are directly trickled down from the flagship Model 60 [HFN Jul ’22]. The Model 15’s alloy chassis maintains the same profile but now has a larger cutout to accommodate the bulkier synchronous motor [see p48], the latter bringing the deck up to speed within three seconds and tightening up any flutter from a peak-wtd figure of 0.03% (DC motor) to ~0.02% here. Peak wow is very low at 0.01%, as evidenced by the ‘sharp’ W&F spectrum [see Graph 1, below]. Intriguingly, the 65Hz noise component seen with the Model 60 and Model 12 MK2 was still clearly visible on the unwtd rumble spectrum but, again, did not punch through to the W&F spectrum. In practice, the through-bearing and through-groove rumble remains consistently in the ‘top drawer’ at –73.5dB (DIN B-wtd), ensuring the screw-down clamp will iron-out ‘less than flat’ LPs without adding mechanical noise.

The partnering 309 tonearm is a familiar sight on numerous SME turntable solutions, and despite not being a ‘one-piece’ tube/headshell model like the SME Series IV, V and VA, still offers a very stable cartridge platform [see CSD Waterfall, Graph 2] with a broadly compatible 11g effective mass. The tapered tube, bearing yoke and counterweight rail are all still fashioned from a single magnesium alloy die-casting, pushing up the first bending mode to ~150Hz with a higher-Q harmonic/twisting mode at 680Hz. As expected, the pre-loaded bearings offer almost zero (<5mg) friction and no detectable play. PM

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

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