
Here’s the part 3 of Dimitris’ Arduino controlled Dual Mono AK4490 DAC project we covered previously:
Following up on Part 2, it’s time to talk about the output stage.
This output stage is the brainchild of my friend Kostas, all I did was lay out the PCB.
It is a fully discreet single-ended class-A output stage, outputting ~2.4V RMS.
More details on Dimdim’s blog. If you missed part 1 and part 2, be sure to check it out.

Looks like Class B to me.
I thought Class A amps had an output transistor that conducts 100% of the time.
This design has 2 output transistors (each conducting 50% of the time), with a third eliminating crossover distortion.
I failed to read past the ‘discreet’, to be honest. In fact, there are some more gems in Dimdim’s posts, see the beginning of Part 2, “Bare with me,…” No Sir, I would prefer to keep my clothes on.
I wonder why he so confidently wrote “single-ended class-A output stage”, especially the single-ended part. Hmmm.