The gentleman who inquired about your room is, I think, on to something. You appear to be trying to use your amplifier as a tone control, and I submit that is the wrong approach. Instead, identify what it is in your system that makes the sound harsh and address that issue.
The room is the most important component. You may well be hearing the harshness of room effects, and I would strongly suggest room treatments. They don't have to look very intrusive. I had an acoustical consultant listen to and look at my room, and he recommended placing "BAD panels" (basic acoustic diffusor, I think it stands for) manufactured by RPG. They are not sound-deadening absorbers, rather they diffuse the sound and disrupt standing waves. They are flat, hang from the wall like a painting, and can be covered in fabric available in many colors. You don't have to hire the acoustician to do this yourself, and it's less expensive treating your room than it would be to replace the amp. Please do that first, then decide if you need a new amp.
The room is the most important component. You may well be hearing the harshness of room effects, and I would strongly suggest room treatments. They don't have to look very intrusive. I had an acoustical consultant listen to and look at my room, and he recommended placing "BAD panels" (basic acoustic diffusor, I think it stands for) manufactured by RPG. They are not sound-deadening absorbers, rather they diffuse the sound and disrupt standing waves. They are flat, hang from the wall like a painting, and can be covered in fabric available in many colors. You don't have to hire the acoustician to do this yourself, and it's less expensive treating your room than it would be to replace the amp. Please do that first, then decide if you need a new amp.