Amp for Vintage Heresy

Some good recommendations above. There are so many great solid state power amps available that tubes should be left for preamps and sources, ime, if you want some warmth and coloration. You need to damp the mid and high frequency horns and the woofer baskets using a Dynamat type material and use self-adhesive sealing tape (used for doors/windows) for the rear panels (between the cabinets and rear panels for a better cabinet seal. Upgrade the crossovers using Crites, get a fast subwoofer (or two), and experiment with raising them off the floor with good solid stands (I prefer the Heresy elevated). BTW, I consider myself quite knowledgeable and experienced with Klipsch, specifically the Heritage line. If PRAT is important to you, solid state is the way to go. You need to determine what sq attributes and characteristics are most important to you. My best, MrD.

When I had my Heresy’s they were a great match with my McIntosh 240. 

Overall I agree with @mrdecibel but really did enjoy a Tube Amp and Tube Pre with my Heresy 1's .  I even ran a Tube DAC with them to take some of the brightness out as they were usually  in smaller room.  My son now has them and uses an old but fully restored solid state Luxman 100U and I was pleasantly surprised how well they sounded.

The crossovers were updated by Crites . I sent them in and they were reasonable to ship and have them do the work correctly. I sent the crossovers in only, not the speakers.

A friend of mine has vintage Heresy speakers paired with a Fisher 500C receiver. It's a good match. It's not a high-end audiophile system but it's fun to listen to. He has a bar in his basement and this system along with a pool table. Great system for the environment.

500c (fisherdoctor.com)