Bass Heavy Headphones?

DT770 80ohm. Otherwise try some of the ultrasones. But I think you will like the 80ohm DT770 most.

DT770 Pro 80 +1.

DT770 Pro 80 +1 as well

I really don't have much knowledge with " Basshead" Cans but I'll tell you one thing. The DT770 has MASSIVE bass, Too much for me personally. I sold them off it was so much.  You put a decent amp behind them and the pure Bass power is outstanding. I could take about 30 mins tops...LOL

lol, the first time I tried dt770 pro's all I could say was "wow" feeling.  You could give them a try, take advantage of amazons return policy :)

If I were in your position, I would just get an amp with bass boost functions.  Have you tried an amp with your sony's?  There are several portable amps available in your price range with bass boost functions.  The fiio E11 has a two level bass boost switch, and it's cheap.  For the same price you could get the cMoyBB, which also has a bass boost function.  Both amps are for portable use.  For desktop I would recommend the fiio e17, also has bass boost functions.  For some extra juice you could get a fiio e09k and dock the e17 with it for a powerful amp+dac combo.  The extra juice would be handy, especially if you decide to try out the dt770 pro's.

Cant comment on that as I have never heard the ab1000.  The dt770's were way too much fun for me :) way too much bass for my taste.  Again, I would recommend trying out an amp, especially since you haven't tried any before.  I know it's tempting to just buy another set of headphones, I should know.  But a simple bass boost for your xb800 may be all you need.

DT770's or any Ultrasone. 

Have you tried "Darth Beyers"

Take a look at this thread: http://www.head-fi.org/t/574825/ultrastone-900-pros-vs-beyerdynamic-dt-770-pro-80-oms-for-dub-dnb

Cool :) and maybe in the near future you could send your dt770's to headphile and they can turn them into the infamous Darth Beyers.

once you get DT770 80ohm, (bassiest and easiest to drive, easier than the 32ohm), you wont need anything else for bass ever again. I know thats a big statement, but im comfortable making it. I produce hophop and hiphop orientated electronica, so i came to this hobby chasing bass, it took two tries to find the DT770. Then i tried others (everything really) and stayed with DT. Then i tried all the impedances and found little difference but liked the 80most for bass and the 250 had the best balance (we are talking half a bees dick though, the 250 can hardly be called balanced, its a fun U shaped thing). THey are also super comfy! Very light, and the pads are made out of velure just like a tacky gangster tracksuit... mmmmm.... velure....

Now i buy cans for other reasons, maybe because my "tastes evolving" (more realistically im addicted to buying this crap and are making excuses for myself as my music hasnt changed one bit), but i dont believe there is a more boisterous and QUALITY brain rattling bass out  there. I say quality because Beyers are still a "studio ready" can *nudge* but they are seriously a step up from the stuff you buy at cd shops or department stores from mainstream brands . I cant make too many blanket statements when it comes to the dirty B word around here or a hoard of grub steppers might swoop down on me like winged monkeys and start cackling about beats by dre and some other retail shelf piece of bass crap they feel they need to defend/justify till their dying breath. Just buy the 770 80ohm, by the sounds of it you really wont regret it.