Linn 500 Solo User Manual

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 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.