Analog amp with optocoupler

[lumanauw]

Is it possible to use linear optocoupler like HCNR200 to make analog audio amp? From input transistor directly to B-E of final transistor?

 

[Eva]

Remember that practical output current is in the range of 5 or 10 microamperes.

 

[lumanauw]

You're right, the output current is small in the linear area.
How about using this diamond-buffer style booster?