Continuum Obsidian/Viper Turntable/Arm Lab Report

Lab Report

Much is made of Continuum's 'nested' flywheel-effect platter, supported on a very substantial, magnetically-assisted bearing. The latter includes a 25mm stainless shaft running in a tungsten sleeve on a ball bearing, placing the centre of the rotating mass some distance above the pivot point. Nevertheless this is a very quiet bearing design, with through-spindle rumble just –72.0dB (DIN-B wtd, re. 1kHz/5cm/sec) and a through-groove rumble of –70.7dB without the screw-down clamp, improving to –71.4dB with the vinyl pressed tight to the platter's surface. I'll remind lucky owners that keeping this surface scrupulously clean is vital!

This upper platter weighs some 7kg, the entire three-piece section higher still at 10kg, but the start-up time remains an impressive 4-5secs courtesy of Continuum's custom 60V DC motor. Although the motor is governed by a high-frequency servo, our sample was running fractionally slow at –0.38% in its 'auto' mode and – as we have seen with numerous DC motor applications – showing some evidence of low-rate drift, below the traditional 'wow' frequency. Conventional peak wow is just 0.05% and flutter 0.06% [see ±35Hz sidebands, Graph 1 below].

The partnering Viper tonearm features a 3D printed 'tube' – the profile determined by FEA – that combines a low 9g effective mass with a controlled resonant behaviour [see Graph 2, below]. Its contoured geometry gives rise to a pattern of low-Q resonances at 118Hz and 180Hz (a diffuse sub-100Hz mode is below the X scale of Graph 2) with mild and swiftly attenuated resonances at 570Hz, 750Hz and 1kHz. The Viper will likely have an uncoloured mid and treble, revealing any pick-up 'bloom', and deferring any subjective contribution to low bass frequencies. PM

1219continuum.lab1

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

1219continuum.lab2

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

Turntable speed error at 33.33rpm 33.17rpm (–0.48%)
Time to audible stabilisation 5sec
Peak Wow/Flutter 0.05% / 0.06%
Rumble (silent groove, DIN B wtd) –70.7dB / –71.4dB (with clamp)
Rumble (through bearing, DIN B wtd) –72.0dB
Hum & Noise (unwtd, rel. to 5cm/sec) –55.6dB
Power Consumption 5W
Dimensions (WHD) / Weight 370x178x350mm / 30kg
Price £49,998 (including arm)
COMPANY INFO
Constellation Audio
CA, USA
Supplied by: Absolute Sounds Ltd
0208 971 3909
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