SME Model 12 MK2 Turntable Lab Report

Lab Report

While this MK2 Model 12's chassis, 4.6kg platter and sintered bearing are all taken from the Model 12A [HFN Sep '19], and the Synergy turntable [HFN Mar '19] before it, the AC motor and two-box PSU/speed controller are directly trickled down from the new flagship Model 60 [HFN Jul '22]. The immediate benefit to the proven Model 12 chassis is realised in its reduced W&F [see Graph 1, below] and 2-3sec start-up (from 4 seconds). The Model 12A's 0.015% peak wow was already as good as might be achieved with a DC motor solution but this sharpens up to <0.01% here – firmly in 'direct-drive' territory! More tellingly, the new AC motor drive has halved the peak flutter to 0.02% and, interestingly, while the 65Hz noise component seen with the Model 60 was also clearly visible on the unwtd rumble spectrum here, it did not punch through to the W&F spectrum...

Now, in case you're thinking the Model 12 MK2 offers Model 60 performance in the round, I'll burst that bubble now. While speed stability is in the 'top drawer', the deck's rumble is a little poorer than the 60's, and the Model 12A's, at –69.5dB through-groove (unaffected by the record weight/clamp) and –70.5dB through-bearing (DIN B-weighted). This, I suspect, is the trade-off between the old DC motor and new, higher-torque/reduced rpm AC motor, but it's absolutely one that advances the Model 12's subjective performance. The partnering 309 tonearm, meanwhile, despite not being a 'one-piece' tube/headshell, still offers a very stable cartridge platform [see Waterfall, Graph 2] with a broadly compatible 10g effective mass. The first bending mode occurs at around 150Hz with a higher-Q harmonic/twisting mode appearing at a higher (midrange) 680Hz. PM

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

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

Turntable speed error at 33.33rpm 33.34rpm (+0.02%)
Time to audible stabilisation 2-3sec
Peak Wow/Flutter 0.01% / 0.02%
Rumble (silent groove, DIN B wtd) –69.5dB / –69.4dB (with clamp)
Rumble (through bearing, DIN B wtd) –70.5dB
Hum & Noise (unwtd, rel. to 5cm/sec) –58.6dB
Power Consumption 17W (12W idle)
Dimensions (WHD)/Weight (inc PSUs) 370x178x350mm / 23.2kg
Price (with arm): £10,475

COMPANY INFO
SME Limited
Steyning
Supplied by: SME Ltd
01903 814321
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