NO other amp will give you more bass or change the frequency response in any way unless it's a broken unit or a heavy tube amp specifically developed to change the FR and add harmonics i.e. distortion. A good amp is always developed such that it doesn't interfere with the sound. The best amp is the one that adds nothing to the signal but amplifies it as clean as possible (maybe adding some character but those features I'll explain in the next paragraph). If you think that changing amps will improve your headphones, you've been seriously mislead. BTW Ananda does not have harsh highs. If you hear them as harsh, they will absolutely be harsh in any situation on any amp with these headphones. That's how you hear, 'cause every person hears differently. Yes, bass is not the strongest feature of these headphones, but man, use EQ for that matter - it's FREE! No amp will give you more bass, including the SA-1, unless there is a switch like the XBass on the iFi Zen Can.
All the nuances we are talking about here in regards to the sound signatures of amplifiers are really minute and can be appreciated by trained ears and music connoisseurs, like trailing ends of tones, micro- and macro dynamics, soundstage width and depth, impact, separation, and so on. But even if we talk about dynamics, simply changing your headphones will give you 99% difference compared to what can be achieved by changing an amplifier.
Of course, you can absolutely disagree with a random dude on a forum who tries to ruin your faith in amplifiers but here is a similar view from Crinacle who, I believe, is not the least person in the audio community: