Vintage

The pulley, belt and freewheel drive mechanism described by Tim in our review is clearly innovative but not without some technical compromise. Specifically, while the high-speed DC motor can be fine-tuned to deliver a very impressive –0.04% absolute speed accuracy, there is still some 'dynamic' drift as the adjustments of the servo are relayed through the pulleys and belts. Visible as a very low-rate wow [Graph 1], amounting to peak-wtd figure of 0.08%, this drift rarely impacts on the listening experience as obviously as might a higher-rate (2-10Hz) wow. Many listeners may well be oblivious... No special claims were made for the GA 202's main bearing and, indeed, the original '–60dB (DIN-B)' rumble specification is hardly extravagant. In fact, the GA 202 achieved a through-bearing figure of –66.5dB (DIN-B wtd) improving to a very creditable –70.5dB measured through the groove – testament to the isolation afforded by the platter and bonded hard-rubber mat.

The short, straight tonearm (effective length 222mm) with offset headshell, exhibits a main bending mode at a low 70Hz with a harmonic/twisting mode at 185Hz – these low frequency resonances being complicated by the sliding counterweight/ collar midway along the alloy tube. There are other, higher-Q, modes at 335Hz and 710Hz more likely associated with the headshell assembly [see Graph 2]. In terms of its utility, however, Philips' sliding collar is very accurately calibrated, each division representing +1.04g of additional downforce. Finally, the 9g effective mass of this delicate-looking arm is, perhaps, slightly higher than might be anticipated, but it is well suited to the ~18cu compliance of the partnering GP 500 MM pick-up. PM