I have grado rs1i phones and audeze lcd rev2 phones as well.I find their tonal qualities seem to be somewhat similar with regard to the midrange.Of course the audeze phones are superior but I was giving you some input in my humble opinion.I have heard the grado amp and was not that impressed with its sound via the Rs1i when I bought mine a couple of years ago.I had opted for another amp.
Of course I have moved on from that amp and presently have two amps.A burson ha-160 and a ray samuels raptor.I find that the grado rs1i pairs really well with the raptor.The soundstage depth fleshes out with this amp and has good bass that is pretty tight for a tube amp.The grado is an easier load for headphone amplifiers than the lcd2 rev2 but both my amps work fairly well with both phones.I am using an upgraded power cord with my amps.I also replaced the stock fuse in both amps with hi-fi tuning fuses.I suggest at least the silver star fuse and posiibly the supreme fuse from hi-fi tuning.The hi-fi tuning fuse upgrades really improved the sound of both of my amps and is worth the effort.The fuse upgrade is very reasonable at 50-60 dollars., The sound improvement is very apparent for such a small cost.
My preferred amp with the audeze is the burson ha-160 for now.The audezes really shine on this amp with the upgraded power cord and silver star fuse. And it does not sound bad with the rs1i either.
I might suggest a new amp to realize the full potential of your grado phones.
Edited by buson160man - 2/5/12 at 11:05pm