When you clap your hands do you get a lot of Slap Echo. Looking at your components real quick nothing jumps out to me. Could be a lot of things but I'd start with your room. Get rid of the echo and see what happens.
Question with your speakers why you're bothering using two amps. Try using only one amp at a time and then try the other. If your room is hot it's really easy to overload the space if you're playing too loud. Cables and other tweaks will help but you have to fix the room first or you'll go crazy and spend unnecessary money.
Speaker placement has a lot to do as well so walk and stand around where you want or prefer your speakers to be and start talking loud and listen to your own voice. You'll be surprised how your voice changes; pick the spot that sounds more natural to you and start there. It takes a lot of work to get it right but you'll get there and learn a lot in the process. Stand with your back against the wall you have your speakers on and listen how your voice sounds chesty; as you walk off the wall your voice will become or sound more natural... get too far out in the room and your voice will get thin. Mark the spot that sounds best with a piece of tape. Now do the same thing on the side wall. You'll end up with an "X" on the floor. That will be a good spot to place your speakers and start making small adjustments.
Start with speakers shooting straight ahead with no toe in. Once you think you have it then mess with toeing the speakers in if needed. Now the fun part... you have to dial the location of your listening seat as well. It's kind of the same process but just work off the back wall centered between the speakers. If you can, never have your listening seat up against the back wall.
Once you get all this dial in; sit in your chair and have someone else walk down the sidewalls with a mirror and mark on the wall with a piece of tape where you see your tweeters. These are the areas you need to address with something to break up or absorb the reflection before it gets back to your ears. This is a lot of work but it works. It helps to have another person to assist to see where they think their voice works best too. Good Luck
