It's neither, actually. If I remember correctly, the iPod's output impedance is actually lower than most of the common SS amps people like to run (ie E7/E9) and all 3 of the iPod, iMac and Little Dot have more than enough power to feed the Denons. When you say they need more power to sound their best, that implies I need to turn them up louder to sound their best, which just isn't true at all.
On to a different note. EQing by ear isn't good either. Our hearing has its own loudness curve, and EQing to the point that everything sounds the same in volume just means you'll have hugely exaggerated low end and really high end. In theory, compensating for computer measurements is the better approach.
The output impedance of the iPod is still too high (denons tolerate at most 3ohms, 3rd Gen iPod touch is 7ohms) and is not nearly powerful enough. Sounding loud and sounding good are two different things. The denons can be "loud " no problem, but its likely you'll run into the v -shaped response curve everyone talks about, or bloated bass. More power equates to better control over the driver, not necessarily more volume.
Edited by scannon18 - 2/21/12 at 4:50pm