OpAmp choice and circuit configuration for DAC amplification to speaker
Well, testing the circuit with a protoboard checked out that it works perfectly, as long as the LM386's power supply is first decoupled with a bypass cap, otherwise we did have saturation noise at the output for frequencies above around 10kHz when we needed to handle up to at least 20kHz. The voltage divider didn't even need to attenuate the signal so much so a 10K resistor on top worked perfectly.

Sorry I don't have more details, we tested this two weeks ago and only now I remembered I had asked for help here.