Quote:
Originally Posted by
nywytboy68 
Try a Cowon dap (J3/S9/D2+) - but don't use the BBE, that actually takes bass and clarity away (IMO). The bass does have a slight roll-off, but it's still highly customizable, and can be adjusted to perfection.
I personally don't use the BBE, as I mentioned above - but you might love it, most do.
Not sure about S9 or J3, but I would not say that D2+ has good bass. Other than the poor amplifier (pronounced bass roll-off), its EQ is terrible especially if one is looking for the deepest bass; 80Hz (the frequency adjusted by the bass slider of the EQ) is not what I would call deep bass. Sure, the combination of BBE/MachBass may sound interesting with some tracks. But never deep. As a matter of fact, that is why I sold my Cowon D2 a couple of months after I bought it - bass performance was very poor.
Apple started using better DAC/amplifier chips in their iPods/iPhones since at least a couple of years or so ago. That means no more bass roll-off (bass roll-off was the reason I sold my Nano 2nd gen) and overall very good sound. Very recently they have also updated the EQ (at least in iPhone/iPod Touch) - no more distortions and decent sounding, however iPod EQs come only with presets so forget about fine tuning the sound and enhancing the very low frequencies.
Sony's are very good with bass - shaking the earth without sweating. It is also deep, but true not the deepest you could think of. I concur with a_recording, keeping your current player and looking for the right earphones would be a good solution for your quest.
Otherwise, rockboxed Sansa Clip/Fuze is also a very good alternative. The internal amplifier is very good and the EQ in Rockbox is all that you can dream of - you can adjust the frequency and the quality factor the way you want it. The deepest bass I've ever heard in a portable player came from my rockboxed Sansa Fuze. However, the impact is not the same as in my Sony's (A829/S729/S515) despite the numerous adjustments options in Sansa.