One thing about the tone controls is that they may not have the effect you really want. For instance my Rotel 1066's service manual states that the treble control operates at 10khz; but I've read that the frequencies that we as listeners associate with harshness/brightness are actually much lower than that, around 4-6 khz I believe. Now the treble probably filters on a slope just like EQ (since it's essentially a very simple EQ), but I would think that if you're trying to reduce output at 4-6khz using a control that has the most effect at 10khz isn't the way to go.
So maybe the resistors would be better in this regard, I don't know. I'm waiting for mine to arrive, and I'll probably give it a try since I can alway change it back.
