Pro-Ject Debut PRO Turntable Package Lab Report

Lab Report

Pro-Ject's Debut PRO turntable/arm/MM combination shares the same PSU, motor and MDF chassis as the earlier X1 [HFN Aug '19] and X2 [HFN Nov '19] models but there's a new nickel-plated bearing here, a new arm (bearing) and 1.6kg alloy platter with peripheral TPE damping. Once again, the deck is supplied with both glued round-section (78rpm) and continuous flat-section (33.3/45rpm) rubber belts but still I'll urge HFN readers to leave the former in the packaging and use the flat rubber drive. The round belt (with glob of adhesive) causes a marked deterioration in W&F [shaded spectrum, Graph 1], rumble and a speed error of +1% that some listeners might mistake for extra 'pace'! By contrast the flat belt delivers a very fine 0.02% peak-wtd wow [black spectrum, Graph 1] with a ±82Hz flutter that's also obvious on the unwtd rumble spectra [not shown here]. We saw the same rumble component on the Pro-Ject X2, and while the bearing rumble here is a little below average at –63.8dB (DIN-B wtd) this improves to –66.2dB measured through-the-groove.

The partnering 8.6in tonearm features the same one-piece alloy/carbon tube seen in earlier Pro-Ject designs but is supported here in a new bearing yoke with a marginally under-hung and decoupled counterweight system. The main tube mode is lower than expected at 75Hz [off the X axis of Graph 2, below] and accompanied by a trio of high-Q and clearly-defined harmonic/twisting modes at 245Hz, 475Hz and 830Hz, the latter possibly associated with the carbon headshell fingerlift. The new arm bearing is well adjusted, free of play and offers low ~15mg friction, but the latest 'superstructure' is clearly livelier than we saw in the X2 model. PM

1021pro.lab1

Wow and flutter re. 3150Hz tone at 5cm/sec (plotted ±150Hz; flat belt, black; round belt, grey)

1021pro.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 33.37rpm (+0.1%)
Time to audible stabilisation 3-4sec
Peak Wow/Flutter (Peak wtd) 0.02% / 0.03%
Rumble (silent groove, DIN B wtd) –66.2dB
Rumble (through bearing, DIN B wtd) –63.8dB
Hum & Noise (unwtd, rel. to 5cm/sec) –55.7dB
Power Consumption 6W (1W standby)
Dimensions (WHD, with lid) / Weight 415x113x320mm / 6kg
Price £699 (inc. arm and cartridge)

COMPANY INFO
Pro-Ject Audio Systems
Austria
Supplied by: Henley Audio Ltd, UK
01235 511166
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