Tell your avr it has no sub connected to it and your speakers will play all the bass they are capable of.
Lower your crossover and your speakers will play more of the bass frequencies in the source material.
Set your crossover and enable your avrs double bass feature, which will allow your speakers to play the full range signal and your sub to play bass frequencies below your set crossover. This can have negative cancellation effects and is not usually recommended.
Simply cutting the power to your sub without telling the avr that it is not in use will eliminate bass below your crossover setting.
I don't need snobs to tell me how to think, thank you!