Humble One. Class A Push-Pull 11 Watt. Uses OPA189 opamp.


Humble One is a small Class A amplifier.
Output is 11 Watt into 8 Ohm and 12 Watt into 4.
The amplifier uses only parts that are possible to find and buy.

Humble One is controlled by a quality opamp, OPA189, for low distortion.

Output devices are MJE3055T and MJE2955T TO-220 transistors.

Bias in output is 1.25A Class A.
The power in each output device is 20 Watt and will produce heat.

Gain is set to x10.
The offset is very low thanks to the CMOS opamp.

Transformer should be 2x12VAC, preferably 100VA.

The circuit is simulated with very good results.


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