Yamaha GT-5000 Turntable Lab Report

Lab Report

Rather than slip and strain the belt, Yamaha's 24-pole, 2-phase AC synchronous motor applies its torque progressively, bringing the GT-5000's 7.2kg aluminium platter/brass sub-platter up to speed within about 12 seconds. As supplied, absolute speed was bang-on 33.3rpm, requiring no fine pitch adjustment, although the peak-weighted W&F is moderate rather than especially low at 0.05% and 0.06%, respectively [see Graph 1, below]. The –69.2dB through-bearing rumble is optimally reduced via the rubber mat option, this yielding a figure of –70.6dB through-the-groove (or –70.2dB with the stiff felt mat, all re. 0dB/5cm/sec).

The straight, statically balanced tonearm has a 223mm effective length and no headshell offset, trading tracking accuracy (and a lack of side thrust compensation) for 'superior rigidity' and groove stability. Rigid it most certainly is, with the bearing all but frictionless at ~5mg, but the tonearm – a carbon-clad copper-plated aluminium tube – exhibits a series of striking high-Q resonances [see Graph 2, below]. The main mode for the tapered tube is deferred to a high 172Hz and is accompanied by two potent harmonic/twisting modes at 430Hz and 730Hz.

Erring on the side of caution, Yamaha's counterweight under-reads slightly, so dialling-up 1.0g yields a 1.08g tracking force and 2g gives 2.18g. Finally, whatever the various tonearm geometries (Baerwald, Lofgren and Stevenson most commonly quoted) might predict for the tracking error and distortion, in practice the THD from my test cartridge increased most steeply at the innermost grooves – from 0.65% (outermost) to 0.75% (middle) and 1.9% (end-of-side), all –8dB/1kHz re. 5cm/sec. 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 33.31rpm (–0.07%)
Time to audible stabilisation 12sec
Peak Wow/Flutter (Peak wtd) 0.05% / 0.06%
Rumble (silent groove, DIN B wtd) –70.6dB (–70.2dB with felt mat)
Rumble (through bearing, DIN B wtd) –69.2dB
Hum & Noise (unwtd, rel. to 5cm/sec) –53.9dB
Power Consumption 9W (0.5W standby)
Dimensions (WHD) / Weight 546x221x411mm / 26.5kg
Price £7000

Yamaha Corporation
Supplied by: Yamaha Music Europe GmbH (UK)
0844 811 1116