Turntables, Arms & Cartridges

Allegiance to LP playback is something of a mission for that indefatigable champion of optical cartridges, DS Audio's President, Tetsuaki 'Aki' Aoyagi. 'I intend to pursue the reproduction of analogue records as can only be done with optical cartridges', he promises. Of course, this latest twist in the DS Audio saga – the Extreme's single-piece diamond stylus/cantilever – is an 'on trend' approach in high-end cartridge design.

'I have learned', says Aki, 'that the sound changes so much depending on whether the stylus is glued or a single-piece. I would also like to make the vibration system lighter to retrieve the stylus tip information more directly'. Research continues beyond the stylus/cantilever but some aspects of the cartridges' basic optical topology seem settled.

Regarding immunity from stray light, Aki says, 'The photodiodes are only sensitive to infra-red (850µm) rays, so interference from outside light is basically not a problem. Also, the cartridge's body shell prevents light from coming in from the side or top'. There is, however, in-depth research being conducted into the optimisation of the light path.

'We are now experimenting with alternative light sources and photo-detectors for possible future use. We will probably not change the wavelength, but there are various options, such as using a lens to focus the light to a more stable intensity. We are also looking at using photo-detectors that offer faster response times and lower [thermal and shot] noise.' Watch this space!