Perhaps a pair of these:
https://www.parts-express.com/pedocs/specs/294-2705--prv-audio-5mr450-ndy-specifications.pdf
-in parallel for net 4 ohm "average". (..the F4 doubles its power into 4 ohms.)
Maybe 14 liters for the two with 90 Hz vent freq..
https://www.stereophile.com/images/styles/600_wide/public/290ae2.promo_.jpg
https://www.parts-express.com/pedocs/specs/294-2705--prv-audio-5mr450-ndy-specifications.pdf
-in parallel for net 4 ohm "average". (..the F4 doubles its power into 4 ohms.)
Maybe 14 liters for the two with 90 Hz vent freq..
https://www.stereophile.com/images/styles/600_wide/public/290ae2.promo_.jpg