The ATH 700 MKII's have great bass. They employ a 53mm driver which is much larger than most phones have (45mm is typical). The soundstage on Audio Technicas is pretty narrow though. If you want a more expansive sound field, I will second the nomination for one of the Ultrasone models. They have loads of good QUALITY Bass. Not the boomy Bass you'd get from any of the Beats or similarly marketed "Rap" headphones, and the highs are detailed, soaring, and clean. Best bang for the buck out there right now if you want an Audiophile quality can.
You want to say I should buy mk2??