I think you have too many variables in play for a single solution. If I may ramble a little. The Klipsch Heritage series has a distinct sound, tubes will improve it, but it’s still Klipsch and will always be bright and lack bass. Also your room acoustics have a huge impact on your overall sound. I’m also amazed @dweller ‘s experience with his Forte’s, that’s hugely disappointing. I have Heresy II’s in the closet that I ran with SS, then tubes. I used subs, rolled tubes and played with cables. I improved the sound , but I still don’t care for them. But keep in mind , many listeners enjoy the Heritage line and that’s great. I would ignore the haters and would consider jumping onto the Klipsch specific chat site and seek a solution for your Forte’s. After reading what dweller said, I’d at least look inside. If there’s any way you could home demo some gear, you could get a better idea of what to do with your direction with speakers and amp. Keep in mind system synergy and room dynamics. On the older Klipsch speakers , crossover rebuilding and diaphragm replacement is a must. In closing I would consider looking inside your speakers. Eliminating any silver cables, and play with speaker placement. I’d also experiment with dampening on and around the mid and tweeters, with tape and soft materials. These are things that are basically free and might yield some insight. Good luck and happy listening.
