Actually... I've not heard that BUT that is a good suggestion! THere are from my undersatnding like 2 [maybe 3] versions of the HP 100
The orignal with >100 Serial Numbers, the first batch which are VERY neutral and have a VERY linear Sub bass with a smidge of reccesed Mid bass. I had that version of teh hp 100
but I hear there are new HP 100's which have more of a mid bass hump or rather linear sub bass and a slight hump to mid bass, which sound a little less balanced over the "sucked out" early model
That said, depending on which HP 100 you have, the newer "warmer" one or the older "sterile" one will depend on weather you want something warm like the X1 or something more sterile like the Akg or the DT 880
Hmm, mine was pretty warm and reached pretty low for my likings. It was my "fun" can when I had it so I doubt it was the version you had.