VegetarianEater, Glad to see you got them working, did you figure out what was causing your shutdown issues?
It is not possible for cabinet leaks to impact the bass output of your speakers to any significant degree, (unless you forgot to put a side on or something like that). The rear port is a giant cabinet leak so you would have to see major gaping holes like that to have any impact. If you put your ear to the rear port you should hear deep bass, but you will not feel a lot of air like from a sub.
In terms of things you could have done wrong that impact the bass - either wiring one of the woofers internally out of phase (hooking the plus wire to the negative terminal) or wiring one of the rear terminals that way, or simply hooking one of them to your amp out of phase is the most likely culprit.
My earlier comments about their great bass had more to do with how deep they get (re: concern over the 60HZ spec on the back label). I think it likely that they have less total bass output amount than your Pioneer Towers, but probably get deeper. The frequency cure for the DIY 2.2A shown on the Hivi Site shows a flat accurate response.
. In my room they sound slightly bright with no EQ or tone controls. When I used a better quality amp the high frequencies sounded more balanced, but I still like them with a 2DB treble cut on some music.
Changing their location in the room, putting them closer to a rear wall will increase the bass a lot.
You could also go through the Room EQ process using the Mic that came with your VSX-80 to see how that impacts things. If they sound hugely different when you do that, their could be something wrong in your wiring, or you could just have placed them in a spot in the room that does not emphasize bass. The built in EQ circuits are one of the best things that has happened to receivers cause you can get accurate sound without changing your room.
If they still sound bass-lite to you after the EQ it would indicate they are accurate but you prefer a more bass enhanced sound. Although using EQ or Tone controls is frowned on by some audiophile types, unless your room has been treated to be perfectly accurate then bumping or cutting bass/treble makes great sense. Every recording studio is heavily EQed because no 2 rooms are the same. You should be able with slight adjustments in placement and EQ get plenty of bass.