I could be wrong here... if you use an open baffle, a woofer would radiate sound waves from the front-side and also opposite waves from behind the baffle , consequently it will create cancelling waves. That's the reason why a woofer out of a cabinet doesn't sound as loud. Some speakers run 2 out-of-phase woofers on an open baffle to compensate for wave cancellation.

The sailor does not pray for wind, he learns to sail. --Lindborg