Pro-Ject Audio Systems X1 Turntable Lab Report

Lab Report

The excellent all-round performance of Pro-Ject's X1 turntable/arm/MM combination surely makes this its very best sub-£900 offering to date. Measured directly through its latest stainless steel/brass/Teflon bearing, rumble is acceptable at –66.7dB (DIN-B wtd), a figure that improves to –68.7dB (through groove) with the felt mat in place and –69.0dB with the mat removed. The efficacy of the latter 'naked' option will rather depend on the flatness of your LPs because I would guard against using a heavy record weight with this deck. The motor is sufficiently 'torquey' that start-up time is a rapid ~3-4secs while absolute speed is a useful +0.1% fast (AC motors inevitably slow with age and use). Thanks to the new drive circuit, both drift and low-rate wow are reduced to just 0.03% [see Graph 1, below] while flutter is a modest 0.05% with mild sidebands at ±13Hz and ±85Hz.

The origins of the partnering X1 tonearm hark back to Pro-Ject's 10CC Evolution [HFN Jun '10] whose lightweight but very rigid carbon fibre tube was revealed to have a diffuse main bending mode at 190Hz but two high-Q resonances at 600Hz and 1.2kHz. Pro-Ject responded to our lab tests by improving the hard carbon tube's internal damping with an alloy sleeve [HFN Jan '16], offsetting these midrange resonances for a stronger but less subjectively debilitating harmonic at 290Hz. The X1 represents a further improvement – a one-piece tube/headshell with a main beam resonance at 170Hz and two harmonic/twisting modes at 280Hz and 410Hz [see Graph 2, below]. The 9.5g effective mass confers wide compatibility with medium compliance MM/MCs while the four-point Cardan bearing offers very low (<10mg) levels of friction. An impressive package! PM

1019project.lab

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

1019project.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 (+0.10%)
Time to audible stabilisation 4sec
Peak Wow/Flutter (Peak wtd) 0.03% / 0.05%
Rumble (silent groove, DIN B wtd) –68.7dB (–69.0dB)
Rumble (through bearing, DIN B wtd) –67.5dB
Hum & Noise (unwtd, rel. to 5cm/sec) –59.3dB
Power Consumption 3W (1W standby)
Dimensions (WHD) / Weight 415x125x335mm / 7kg
Price £699 (inc. arm and cartridge)
COMPANY INFO
Pro-Ject Audio Systema
Austria
Supplied by: Henley Audio Ltd, UK
01235 511166
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