Re: Sundown neo pro 8s/6.5s
Like any speaker in a car door, they need to be in doors that are dead and they need processing in order to get the best out of them. I have 8s in my doors and will be adding two more, although I'll probably go with CT Sounds' PA 8s once they ship.
The Neo Pros, like other sundown drivers, handle more power than they're rated for, get loud and have excellent sound quality in properly deadened doors with processing.
Although it's not as critical in door speakers as subs, I wouldn't recommend different sizes in the same air space.
As for bass, they are mid bass drivers, not woofers and not subwoofers. You might be able to squeeze some bass out of them at 60Hz and low volumes but I wouldn't push them any lower on any reasonable amount of power.
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