Appreciate the compliment Expat, but don't be fooled by my barely passable pretensions to being either.
I also appreciate the app recommendations and I spent most of yesterday playing around with both EQu and Equalizer.
My hasty conclusions are that all of you (Expat, Achmed, and Smilelizzy) are correct in having a preference for Equalizer's accuracy. I definitely found it to be less damaging than EQu, but I did prefer EQu's interface. However, I'm left feeling the same about EQ overall, which is to say:
The EQu and Equalizer apps for iPhone do exactly what I would expect a half decent EQ to do in that they give the user a tool to modify the frequency response of his/her entire setup, which is an interesting diversion, but does not really improve SQ in my view. More or less bass, mids, or treble can certainly "smooth over" poor recordings or even ameliorate either gross deficiency or gross profligacy in an IEMs frequency response curve, but for me these adjustments don't really amount to an improvement in SQ. For me SQ is the sum of those elements that make the playback sound real, that make me turn my head to the left to see the palmista who shouts "Allez" (or it's Spanish equivalent) 42 seconds into Estrella Morente's Bulerias de la Bolla on "Mi Cante y Un Poema." Assuming that you are starting with a decent recording and playing it back through a decent rig, EQ never helps bring that moment alive in my experience and, in fact, usually dulls that moment anywhere from just a smidgen (with the best EQ) to massively (with Apple stock EQ). Good amplification on the other hand makes the TF10 go from painting the cry in starkish relief (via iPod/iPhone HP out) to actually making me turn my head to look for the palmista (via RSA Hornet).
Edited by NewAKGGuy - 5/16/11 at 10:30am