The IC is mounted on the cooling radiator with 4 mm aluminum plate. Usage of termo-silicone paste is mandatory. To maintain power of 100 W additional cooling is needed otherwise you can experience 50 % drop of power.
ATTENTION!!! Before submitting VOLTAGE MOUNT THE RADIATOR!!!
It's recomended for rectifier of the amplifier to use 150 W transformer with twi secondary voltages from 20 to 30 VAC, bridge rectifier 6 A, electrolytic capacitors from 2000 to 4700 mF / 50 V or 63 V.