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Linn 500 Solo User Manual

Page 18

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10

The arguments about the relative merits of tubes, MOSFETS and bipolar

devices have filled many technical journals, and needless to say, most are

over stated and over simplified to try to win the argument! It’s possible to

design a good amplifier using any of the available technologies. Turning it

into a great amplifier takes more than just a good argument. In the Klimax

we chose bipolars running in Class AB and put in the essential circuitry to

take maximum advantage of the inherent linearity of bipolars (unlike

MOSFETS), and to manage their potentially slower switch off characteristic.

Many MOSFET designs neither adequately linearise the MOSFETs, and in

the assumption that ‘they are easy to drive’ don’t put in adequate circuitry

to take advantage of their potential switch off speed. However, if we ever

decide to make an amplifier above 500 Watts we would most probably use

MOSFETs.

To run a system of amplifiers of the Klimax power in Class A would heat a

house, very expensively, after laying in a high current three phase mains supply

to the house. So we chose to use Class AB with the circuitry necessary to

control precisely the handover from one power device to the other.

To avoid having capacitors in the audio path the Klimax is direct coupled

with a dc servo to minimise output offset voltage.