Excellent post, and I think you nailed the Grado sound transition in the SR line since the 'E' series was launched. I had a 325i many years ago, and even for me (I love the Etymotic BA "house sound"), it had spikey treble that was hard to tame down. I retried the 325E about 2-3 years ago and was super-impressed with the smoother and yet still alive sound. I kept them for several months and loved them, until I got hold of a used GH2 cocobolo, then RS2e, then PS500e!!Here are my Grado SR 325X > Impressions.
Right out of the box.
I've listened to Dub, Rock, Country, Ambient, Jazz, Jazz Vocal, Bluegrass, and Classical.
First things first......
I've not tried the Hemp, nor any of the new X series, but am assuming they will sound closer to my PS500e, with a fuller sound in the 500hz and below region.