Arduino AC Signal Creation

Okay I understand.

If I used my PWM output to create the 'average voltage' using the duty cycle. This signal then into a DAC and then into an Op-Amp?

This will create my AC signal matching what I need in the first post?

Will the reaction time with these 3 components be quick enough? The voltage switches from roughly +6v to -6v in 0.5 micro seconds.

Many thanks!
Max