Dual CS 5000 Turntable Lab Report

Lab Report

Nearly forty years since this CS 5000 rolled off the production line its absolute speed error is still only a mere +0.075% fast. Speed stability is a little less impressive, however, with some very low-rate DC drift and higher-rate wow at ±8Hz amounting to a peak-wtd figure of 0.8% [slightly lower than measured in HFN Oct '86, see scans lower left]. The complex series of peaks that make up these sidebands [see Graph 1] are also visible on the unwtd rumble spectra [not shown] as are two distinct peaks at 44Hz and 88Hz that, presumably, are linked to the refresh rate of the quartz-locked speed control. The DIN-wtd rumble measurements provide a somewhat brighter picture as the figure of –67.4dB obtained directly from the sealed bearing improves to a very respectable –69.5dB through-groove, thanks almost entirely to the heavyweight rubber mat supplied with the CS 5000. I should add that the motor is not especially 'torquey' (no bad thing) so start-up time is a slightly sluggish 7 seconds.

The 8.7in (221mm) effective-length tonearm has a lightweight alloy tube and plastic headshell with an overall effective mass of just 9g – ideal for the 5g bodyweight/35cu compliance of the partnering Ortofon MM pick-up. The arm is not especially rigid and so the primary bending mode is sub-100Hz [off the left-hand edge of the X axis in Graph 2] with higher harmonic/bending and torsional resonances revealed at 195Hz and 300Hz. The cardan bearing offers low friction, and the spring-loaded downforce/anti-skate is calibrated within ±10%, but the semi-auto operation brings with it some additional complexity that's likely reflected in the short-lived, high-Q modes at 730-990Hz on the CSD waterfall [see Graph 2]. PM


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


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

Turntable speed error at 33.33rpm 33.36rpm (+0.075%)
Time to audible stabilisation 7sec
Peak Wow/Flutter 0.08% / 0.03%
Rumble (silent groove, DIN B wtd) –69.5dB
Rumble (through bearing, DIN B wtd) –67.4dB
Hum & Noise (unwtd, rel. to 5cm/sec) –60.9dB
Power Consumption 5W (4W standby)
Dimensions (WHD) / Weight 440x125x400mm / 8kg