i got iphone 4s+shure se215
and i'm looking for to buy portable amp
The budget is 60$
i think about cMoyBB
what you guys say?
My 2c. The SE215 like most of the Shure IEM line are extremely sensitive, and can be driven by your iPhone more than adequately - you''ll deafen yourself before you get the volume to maximum (although I haven't tried the SE215, I have owned the SE315, 420, 425 and currently own 535s - oh an I have an iPhone 4).
When I'm using my 535's I nearly always use them straight out of the iPhone or iPod Touch - saves the bulk of using an amp - and to be honest, and difference in SQ is negligible (even using my Arrow). The Arrow is great for my full sized cans - but I simply don't need it for my IEMs.
If you really want to spend $60 - add a few more dollars to it and go buy yourself a set of Grado SR60i. They don't need amping either. Then go enjoy the music.
Don't worry about an amp until you actually need it. And don't believe all the threads stating "night and day" differences when amping sensitive cans / IEMs. Most of it is in their heads IMHO.
The O2 is above his price bracket at $156 USD, and it's massive for an iPhone, it's more like a desktop amplifier.
The iBasso D-Zero comes with a DAC inside of it too, and with theoretically via a mini USB cable override the internal iPhone DAC in a smartphone, thus improving the sound-quality more than the O2 ever could dream of.