Pro-Ject 175 Vienna Philharmonic Recordplayer turntable Lab Report

While the bare bones of this limited edition deck are culled from Pro-Ject's 'The Classic' turntable [HFN Aug '16], the wooden chassis, alloy platter and – particularly – the stainless steel/bronze bearing look to have been enhanced. For example, while the same AC motor drives the platter up to speed over a slightly longer 5secs, and the absolute speed is still an imperceptible –0.16% slow, its wow and flutter – its dynamic speed stability – is markedly improved at 0.02% and 0.03%, respectively [see Graph 1]. Through-bearing rumble is also 2dB improved at –73.0dB (DIN-B wtd) with the Vienna deck, although this model did betray a discrete mode at 41Hz in its rumble spectrum.


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

The partnering S-shaped 9in tonearm is heavily chromed and features a magnetic insert halfway along its length, plus a polished brass headshell with a 'clarinet flap' fingerlift. So perhaps the whopping 25g effective mass should come as no great surprise... What this does suggest, however, is that only low compliance MCs are really suited to this tonearm – even the supplied 11g Cadenza-derived MC, with its 16cu dynamic compliance, realised a low 6.5Hz arm/cartridge resonance. An Audio Note Io would make a better, if costlier, partner!

Otherwise, S-shaped arm tubes typically exhibit a complex series of bending and torsional modes and Pro-Ject's heavyweight is no different. There is a diffuse main bending mode at 65Hz followed by a series of other modes, possibly harmonics, at 260Hz, 330Hz and 410Hz [see Graph 2]. The high-Q modes at 800Hz/1kHz look to be associated with that fingerlift but it'll be passing footfall and rippled LPs that must be guarded against to avoid exciting the arm/cartridge resonance. PM

Turntable speed error at 33.33rpm: 33.28rpm (–0.16%)
Time to audible stabilisation: 5sec
Peak Wow/Flutter: 0.02% / 0.03%
Rumble (silent groove, DIN B wtd): –68.4dB
Rumble (through bearing, DIN B wtd): –73.0dB
Hum & Noise (unwtd, rel. to 5cm/sec): –62.2dB
Power Consumption: 2-3W
Dimensions (WHD) / Weight: 462x131x351mm / 13kg
Price: £6500 (inc. arm and cartridge)

Pro-Ject Audio Systems
Supplied by: Henley Designs Ltd, UK
01235 511166