I'm not sure why you want to bypass the crossover, as long as you can turn it up high enough to get it out of the way; even for "audiophile" type reasons, I wouldn't bother. That'd be the last thing I'd tweak! Sounds like you've got it hooked up optimally.

Unfortunately, I don't know enough about that sort of thing to know why you got the bad sound going through the sub except maybe they were being passed through a cheap crossover in the process? That would make sense, though (that the sub would want to strip the bass off of the mains, so that you didn't get double-bass).

Meanwhile, set the 1050's xover setting to as low as your mains & center can handle it, so that the sub is playing as low as possible (and leave the sub's crossover as high as possible).