PAST MASTERS: SONY WM-D6C
Tim Jarman brings you this definitive guide to one of the best sounding cassette decks ever made, Sony’s classic Walkman Professional portable.
To any nineteen-eighties audiophile, the Sony WM-D6C – the ‘Walkie Pro’ to its friends – was one of that decade’s most iconic products. Not only was it the ultimate Walkman, but by virtue of its superb engineering happened to be one of the finest sounding cassette recorders that money could buy, full stop. That’s right, in some respects it beat even the top Nakamichis of the time – despite being smaller than a paperback book. Although it was based on technology which preceded any Walkman, it was never bettered and remained in Sony’s personal cassette line-up almost to the end. In the fast-moving world of Japanese hi-fi, that was quite an achievement.
One of the reasons for the success of the WM-D6C was its impeccable pedigree. The machine’s origins lay in the TCM-600 (TCM-100 in some markets) ‘Pressman’ model of 1978, a pocket-sized mono model intended for newspaper reporters and business people. Despite being the smallest cassette recorder on the market at the time, the Pressman is remembered only for one thing – it formed the basis of the 1979’s TPS-L2. This was the world’s first personal stereo cassette player, the machine which would achieve global fame as the Walkman a year later.
This updated model added to the strengths of the WM-D6 by offering an important extra feature: Dolby C noise reduction. This system, which operated in playback and record, improved the dynamic range considerably. Including Dolby C noise reduction in a compact portable was not easy, and the integrated circuits which performed most of the functions had to be made by Sony themselves. The fact that this extra function could be fitted to the WM-D6 without making it any larger was amazing, though it forced some changes, for example the second headphone socket was no longer fitted.
Other useful modifications were made at the same time. Most useful of these was the addition of a line-in connector, which allowed direct connection to other audio equipment without having to use the microphone socket. This was a great improvement and helped to reduce the background noise level when recordings were made from line sources, such as a CD player, second tape recorder or a mixing desk. The level meter was also altered so that as well as showing the recording level or the battery condition, it could be switched off to save battery power.
The WM-D6C can easily be identified from the earlier WM-D6 version because the “professional” script on the top cover is green instead of yellow. The WM-D6C could not really be improved upon and so remained in production almost unaltered for many years. However, two significant changes did occur, both in the latter part of the production run. Firstly, the excellent and very effective amorphous head with its distinctive parabolic grind was replaced by a simpler, cheaper permalloy type of a cylindrical section. This later head is noticeably more wear prone and therefore could not be considered an improvement. Only latterly was the “amorphous head” script removed from the badge on the front of the machine so it cannot be used as a reliable guide to which type is fitted. Secondly, the printed circuit was re-drafted to use surface mounted components. These were much smaller than the types used originally, though as the size of the recorder stayed the same the only advantage was a reduction in the cost of assembly. The circuit remained substantially the same as before and offered near identical performance.
由于使用了表面贴装组件，后期 WM-D6C（底部）的主 PCB 底部比早期版本（顶部）更加稀疏。