Turntables, Arms & Cartridges

Although both decks include their fair share of German technology, the Pro-Ject A1's internal MM phono stage is a different design, built to different compromises, to that in Thorens' TD 202 [HFN Jan '22]. Nevertheless, like the Thorens solution, the A1's fixed +33.8dB gain is someway short of the +40dB to +50dB expected for an outboard MM phono preamp. However, the A-wtd S/N ratio remains generous enough at 78.4dB (re. 5mV input) and proper thought has been given to 'building in' a usefully wide input overload margin.

While this was the TD 202's Achilles' heel, the A1's tethered output holds to <1% THD until the cartridge output exceeds 84mV – equivalent to +26dB headroom beyond the 4mV (1kHz/5cm/sec) of the supplied OM10 pick-up. So, not only will this accommodate the fiercest grooves in your collection but the output enjoys a low ~0.01-0.003% mid/treble distortion, only increasing to 0.1%/20Hz [red trace, inset Graph]. This increase in bass THD, and output impedance (from 100ohm/1kHz to 2.4kohm/20Hz) is linked to the A1's inbuilt subsonic filter (–3.5dB/20Hz to –6dB/13Hz). The latter will cool the worst excesses of any warped LPs while the slightly 'bright' +0.4dB/20kHz presence/treble top-end might add some sparkle [black trace]. PM