What is the best way to tame a slightly bright speaker?


I know the answer is get a speaker that isn't bright,  but I've got a pair of TAD Evolution Ones that I like quite a bit except that the magnesium midrange and beryllium tweeter are just a little bright for me.  I'm driving them with a D'Agostino Classic Stereo, which I needed to drive my old speakers but I don't need all that muscle for the TADs (89db sensitivity, 4 ohm impedance {doesn't drop below 4 ohms}) recommended power 50 to 250 watts. 

I'd like to get  an amp that does voices especially well.  I know somebody posted recently that a subwoofer solved his brightness problem and I may look into that at some point.  Any and all suggestions are welcome.
128x128tomcy6
Often that 300 a side SS Amp is clipping a lot more that you might think .Micro-seconds sound harsh .
Thank you everyone for sharing your ideas and experiences.  There's a lot to try in your suggestions and I'm sure something will work.  For fellow Evolution One owners, yes they are really good speakers.  I'm looking forward to getting them sounding their best (or close anyway).
take the crossover out and lower the non polarized cap to the tweeter, if its 1.0uf drop it in half.