I've heard those M-Ls, and they sounded, to me, anything but ragged in the upper-mid/lower-treble range. They were driven by a SS amp and tube-pre, with computer files as a source. FWIW, as my system has evolved, I have gradually lost any edge or excessive brightness in this very sensitive range. I can now listen to those bad recordings without engaging my McIntosh preamp's tone controls, and enjoy them. I went from asking, "what the heck was the recording engineer thinking?!" to "Oh, so that's what they were hearing in the control room when this recording was mastered!" Yet, audiophile recordings still sound wonderful. I actually had a parametric EQ for the same purpose as you want one, but sold it after I realized I wasn't using it for listening any longer. I got there through numerous upgrades of equipment, speakers, cables, etc. I like having the tone control option, but I like not having to use them even more. I think your M-Ls are fully capable of providing enjoyable listening, even to poor quality recordings. You need to rethink your system synergy and try some new things. And don't ignore your room acoustics, either.
Adding Tone Controls?
My system sounds wonderful when playing well recorded jazz, classical, or "audiophile approved" material. Unfortunately, mass market pop frequently sounds horrible, with screechy splashy highs. It's obviously recorded with a built in bias to be played on car radios or lo-fi mp3s.
What can I add to my system to tone-down the highs on this sort of material? Sure, there's plenty of well recorded material to listen to, but there are plenty of pop rock bands I'd really like to explore if the recordings could be made a bit more listenable.
What can I add to my system to tone-down the highs on this sort of material? Sure, there's plenty of well recorded material to listen to, but there are plenty of pop rock bands I'd really like to explore if the recordings could be made a bit more listenable.