just using the reference on the audyssey and pumping up the bass freq on the EQ dont help much

well the towers can play proper with a good amp but im a bit annoyed they sound so bad without the sub
Try Reference Level Offset of Zero (0). Increase the Trim Level (speaker channel level) by +3.0 or more (like +6.0, +9.0). Of course, turn on Dynamic EQ and see if that helps.
When towers don't sound very good without the help of subwoofer bass, it is usually NOT because the towers need more power.
It's usually because you need different full-range towers, like ones with ACTIVE bass control that allows you to adjust the bass.
My towers have active bass control. I use Audyssey XT Dynamic EQ for bass EQ. And the bass quality (punchy, dynamic, musical) from my towers is better than any subwoofer I have ever owned.
But many towers are unable to reproduce bass that is as punchy and dynamic as some subs.
Is there a reason you DON'T want to use the Subwoofer?