Leaving this drop for fear of the treble, and possible lack of bass with an AMP. I am getting the NarMoo S1 instead as I lack a portable AMP and saw no reviews explicitly using these without an AMP. $34 on amazon with my Prime free 2-day shipping and no risk of me not liking them, I feel like its a win-win for me. Too bad I couldn't get a reply in time to determine if treble really is a problem or not, but my budget is close to nill and I cannot take risks.