Linn Twin Klimax - Manual (Page 12)

So what’s the problem?
The first problem is that this is a lot more complicated than a mains transformer (a few kilos of copper and
iron), a rectifier and some large capacitors. A switch mode design optimised for minimum part count will still
have many tens of parts, most of which are quite delicate but still have to operate reliably in a very
electrically hostile environment. We have been designing and building switch mode supplies for our CD
players, tuners, preamplifiers and multiroom components for several years and can now make them more
reliable than the conventional transformers they replaced. But this takes persistence, thoroughness and a
very consistent high quality manufacturing process.
The second problem, which is what stops most manufacturers considering switch mode for audio, is the
potential high frequency electrical noise, or more precisely, preventing the high frequency signals becoming
electrical noise. The scale of the problem is quite daunting. The high frequency signal applied to the
transformer if connected to an external antenna would obliterate radio reception for miles around (please
don't try this at home!). This must be controlled and reduced so that it not only meets international legal
regulations but it must also not cause any audible or measurable interference with any of the audio
circuitry. This does not happen by accident, but takes experience, thorough precision engineering and
diligent quality control. Only when all of this is achieved can the potential audio benefits of switch mode
start to be revealed and exploited.
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