How did you go?

Before providing the (somewhat incorrect) advice already offered, we really should be seeking to know more about how your system is set up.
I know Morel products very well (I used to sell them and I also had a full Morel system in my last car).

I'd suggest, based on what you've said, that you might simply want to make the tweeters quieter relative to the rest of the sound.

This will make the sound more pleasnt, particularly when you turn the volume up.

Above anything else first, look at where your drivers are and how they're installed.

Can you tell us more about how and where they are installed?
Mids in the doors and tweeters on the dash/pillars?
Are the tweeters facing straight at you?

That sort of thing.

I'd be paying attention to this first before using the band aids spoken of here previously - high passing this, amp settings that, putting in bypass capacitors here, blah, blah, blah. Forget all that for now (and some of it forever).

So, tell us this frst and I'll advise you from there...