pelo911...the fact that your speakers have almost no bass and that your Pass Lab amplifiers are able to deliver the current and output power to drive those bass woofers very well, suggests to me you have a speaker placement/room interaction problem. By the way, how much time have you put on your speakers? Remember there is lengthy break-in for speaker drivers and crossover components before the speaker can sound its best. If you have very few hours on your speaker right now (say less than 50 hours) then I would run them continuously for a week (preferably 2). I would set a CD or your PC on repeat and have a music signal running through the speakers continuously. If there is no one home during the day and there are no neighbors close by to complain, crank the volume up and give those speakers a work out. In the evening and at night time, dial down the volume and if at night you want to make the sound even less bothersome, position the speakers facing one another maybe a foot apart and on one of the speakers, switch the speaker cables at the terminals (that's called wiring them "out of phase") and even cover them with a blanket and let them play (you will hardly hear any sound). So that is advice number one: break in your speakers properly and log some hours on them.
Advice number two is when you have completed speaker break-in above, is to place them back where you currently have them positioned and play some music that you know has some bass on it. If the speakers still sound weak in the bass (especially as compared to the Focal 1038Be's that you had before), then the speaker's position in the room is such that at your listening position, you are experiencing a "suck out" somewhere in the bass frequencies. So what you will have to do is start experimenting with the speaker position relative to how close it is to the back wall and the side walls and see where the bass starts to sound fuller, more clear and differentiated (i.e., more articulated) and where ultimately it starts to sound natural to you (i.e., an upright bass sounds like an upright bass, or a drum kick sounds like a drum kick, etc...). Do this positioning exercise one speaker at a time and when you find the position for each speaker that works best where the bass on each speaker sounds right to you, then you can play around with how far apart they are to give you the best center fill image and how much to toe them in to give you the right balance between soundstage width and treble smoothness.
Once you visit Dave Baskin at DAV, speaker positioning may be something he can advise you on as well. I can guarantee you though that it's not your Pass amps that are the cause of the weak bass you are hearing. Those amps can drive the bass woofers on your speakers very easily and can push enough current to make the Maestros sing. I am not saying you should not consider other amplification as you may prefer different amps with your speakers but just that your amps are not the cause of the weak bass you are experiencing.
Hope this helps.