Linn Twin Klimax - Manual (Page 10)

3. How does the Klimax work?
In most power amplifiers the power supply comprises a large transformer, a rectifier and reservoir
capacitors, often as large as the transformer. The highest performance amplifiers also have voltage
regulators which maintain the power supplied to the amplifier circuitry constant, regardless of the input
voltage or the output load. The bulk of these components dominates the size of the amplifier and the
'tightness' of the audio path, and if voltage regulators are present the power dissipation of the amplifier
increases by up to 50%, requiring a bigger heat exchanger. This conventional type of power supply is simple,
reliable, tolerant of overload and predictable. On the down side it is very bulky, heavy, slow to respond,
inefficient, causes high mains power distortion, can cause electrical and acoustic noise and requires a
relatively long and exposed audio path.
In the Klimax amplifiers we use a technology we have been developing and using in our low power
products for several years, called 'switch mode'. This concept is not new; it has been used in computers since
the 1960's, however applying it to audio has always been considered, at best, inappropriate. The potential
benefits of switch mode power supply technology are compactness, high efficiency, fast response, good
mains input tolerance, good load tolerance, low acoustic noise and with its low material use, environmental
friendliness. The potential downsides are electrical noise, high complexity and potentially lower reliability,
complex certification requirements, design difficulty and high engineering cost. These have kept switch
mode out of most audio equipment.
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