AVM Rotation R 5.3 Turntable Lab Report

Lab Report

I discussed AVM's 'Elipso-Centric Belt Drive' in our boxout but while this demonstrates potential it cannot offset the low-rate drift measured from the R 5.3's DC motor or correct the slight –0.3% error in absolute speed. The drift, illustrated by the lack of sharpness in the 3150Hz test tone [see Graph 1], amounts to a peak-weighted W&F of 0.25%, which is a little disappointing by contemporary standards, as is the belt which, as supplied, is glued rather than continuous and responsible for a faint 'tick' as it passes around the pulleys. Nevertheless, start-up time is good at a few seconds. Furthermore, its through-groove noise is impressively low at –70.1dB (DIN-B wtd, re. 1kHz/5cm/sec), the test LP's impedance match with the 5kg acrylic platter successfully attenuating the through-spindle (bearing) rumble figure which is slightly poorer at –67.9dB.


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


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

The partnering 10in polished alloy tonearm is a medium/heavyweight, but the effective mass of 16g is well suited to the low 15cu dynamic compliance of the partnering Ortofon Cadenza Black, resulting in an acceptable system resonance of 8Hz. MCs with an even lower compliance and bodyweight between 8-12g may prove a better match still. Arm bearing friction is low at ~10mg in both planes and play is undetectable but the main bending mode of that long and heavy tube is an unusually low 38Hz with minor harmonics out to ~300Hz [see Graph 2, above]. Interestingly, this same mode is clearly visible on the through-bearing and through-groove rumble spectra [not shown here]. Otherwise, the higher-Q modes at 560Hz and 900Hz are mild by comparison and probably linked to the plate-like headshell and (in our sample) slightly loose fingerlift. PM

Turntable speed error at 33.33rpm 33.22rpm (–0.33%)
Time to audible stabilisation 3 seconds
Peak Wow/Flutter 0.15% / 0.10%
Rumble (silent groove, DIN B wtd) –70.1dB
Rumble (through bearing, DIN B wtd) –67.9dB
Hum & Noise (unwtd, rel. to 5cm/sec) –54.9dB
Power Consumption 7-9W (1W standby)
Dimensions (WHD) / Weight 470x175x390mm / 12kg
Price: £5490
AVM Audio Video Manufaktur GmbH
Supplied by: The Professional Monitor Company Ltd
01767 686300