So I'd tweaked the frequency response of my phones to be as smooth as reasonably possible as per PiccoNamek's tutorial (with some caveats outlined here). The sound has taken a quantum leap in improvement (physics be damned) but there were still problems. In particular, some songs from old albums by Miriam Yeung (Hong Kong pop singer) had ear-splitting sibilance, and the guitars at Jimi Hendrix--Live at Royal Albert Hall sounded more and more like chainsaws as the concert progressed (the latter is obviously intentional--even feedback whine got into the list of effects used as the last song is titled "Smashing of the Amps", FFS 
) and no reasonable amount of EQing down the treble would take the edge off these albums. UNreasonable amounts of EQing barely made them bearable, at the cost of making everything sound like it's coming through a damp cloth <--)
A search through google and dimly remembered sound engineering classes turned up de-essers and multiband compressors (essentially the same thing) as a possible cure. And boy did it do the job right!
What these can do is shave off just the peaks of particular offending frequencies without changing the sound of the rest of the music.
- those offending ssss's are toned down
- you don't have to turn down the treble, meaning that you can keep on listening with Etys or even Grados and retain their signature sound even on these problematic tracks.
- with detailed cans "treated" to take out the ssss's I would describe the sound as analogous to tone-mapping treatment of Hight Dynamic Range photography, where you can hear every little detail / see into all the dark parts without the cymbal crashes / ssss's / anything too closely miked / the sun deafening you / blinding you.
- can be applied to bass frequencies as well as treble, if you find the loudest bass lines overpowering but don't want to reduce the bass presence in other parts of the music
- more aggressive compression of the bass and treble makes for a very relaxing sound for long listening sessions without compromising quality of vocals
- the moving needles on a multiband compressor like this even make a really neat visualization effect:
I've been experimenting with platinumear's 5orcery 5-band compressor with good results:
http://platinumears.com/5orcery.html
I wasn't able to load the de-ess preset, so I just set the crossover frequencies for the two highest bands at 2kHz and 5kHz, left everything else on default and just tweaked the compression threshold slider until I was getting a good few dBs of reduction on those ssss's. Very simple and easy to use (after you figure out how to load VST plugins), although I wish that the crossover frequencies were more flexible and that it had a setting for the compression ratio.
VST host plugin for foobar2000:
http://www.hydrogenaudio.org/forums/index.php?showtopic=84947
Install the VST host by copying foo_vst.dll to the Components folder of your foobar2000 install, then follow the instructions on this page for loading VST plugins:
http://wiki.hydrogenaudio.org/index.php?title=Foobar2000:Components/VST_adapter
Edited by Joe Bloggs - 7/18/11 at 8:32pm
