Help! My system is very bright it hurts my ear

I agree with losing the biamp for now; simplify your system and use one amp until you stop the offending brightness.
 
Then address treating your room for best sound. Can you answer these questions, please...
- What are the dimensions of the room? We only know that it's a high ceiling.
- Do you have carpeting or bare floors?
- Do you have bare walls? You'll need to have wall hangings or furniture against the walls so that sound waves don't bounce around.
- How far away from the speakers is your listening position?
- Have you done any reading about how to use acoustic room treatments?

What is the floor material in your room? If your’e playing your music to decent or moderate levels and your room is very reflective or lively no cables, or putting a tissue over the tweeter is going to fix things. I’d try only one of your amps and plug it directly into the wall not using the Monster. As someone earlier I think mentioned, you need to simplify things. It will be easier to solve your problem with less going on.

If you have purchased any of your equipment from a local store ask if someone there would visit your home to hear it first hand. Most experienced audio salespeople know how to set a system up properly.

If you want to rule out its not your gear but your room, set it up in another part of the home in a smaller room with lower ceilings if possible. A large room with 20ft tall parrallel walls is going to be a bear to control. I don’t have even be there to have an idea how it must sound. You need to deaden the room, reduce the slap echo and have furniture such as bookcases up against the walls to break up the reflections; read up on standing waves. If you have a hard surfaced floor throw down a nice heavy rug between your speakers and you. If you have a big glass coffee table in between you and the speakers you need to cover that while listening.

If you have this big room with tall ceilings and you’re a minimalists / contemporary dweller with a sparse finished room that’s not helping you. Just guessing on your room here. The point is, that room needs objects and absorbent materials to control room modes. Get your hand clap to have less echo and ping in your room and you’ll be happier. Think how it sounds when you clap outdoors. That’s your reference. Good luck.

I have wood vaulted (timber frame) ceilings in my home theatre room 17' high 24'x28'  it has two sofas, a projection and 5-1 set up it has been a challenge to tame the highs.I would bet the bulk of your problem in placement and room acoustics.imo

Fatgosil, I’m not sure if you are realizing that a passive biamp arrangement, which is what you appear to be describing, will not provide proper tonal balance unless the gains of the two amplifiers are equal or close to it, or if differences in their gains are somehow compensated for externally to the amps.

I couldn’t find a gain spec on the SE-40, and in the absence of a spec there is no reason to assume it is similar to the gain of the 8008.

I realize that you have tried using at least one of the amps by itself and still perceived brightness, but it is very conceivable that multiple factors are contributing to the problem, including gain differences between the amps. So as Lowrider and others have suggested I would do any further troubleshooting using just one of the amps running full range. And try each of them if you already haven’t, and use whichever sounds less bright. Which one will sound less bright depends in part on the relation between the output impedance of the amp and how the impedance of the speaker varies over the frequency range, and I can’t say which amp that would point to because I couldn’t find an impedance curve for the speaker.

Also, to be sure that something simple isn’t being overlooked, have you removed the jumpers from the speaker terminals when you have been using the two amps?

Regards,
-- Al

Al is right on.
Biamp REALLY sucks. 
Use single Aragon first and see what happens. I don't think that Golden Tube will be good enough for Galos.
Gud Luk