Here the great 35W power amplifier with single IC STK-082 from Sanyo Semiconductor. Simple circuit with high power output.. 
This circuit uses symmetrical (dual polarity) power supply with maximum power voltage is 43V based on the datasheet document. The recommended voltage operation is +/- 30V. For stereo application, you just need to build two similar circuit. Use minimum 2A center tap transformer for stereo channel amplifier.
Use this kind of dual polarity power supply circuit:
STK082 Features:
- @lMST, l Channel by 2 Power Supplies
- Differential amp. constantc current driving.
- Capable of tone controlling.
Download the STK-082 datasheet from the following link:
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