Subwoofer Set up Question

Your setup ideas are exactly how I do it! I'm using a pair of ADS 1590/2's full range, and using the high level input on my Velodyne 1500R, and set the crossover to 40hz and the level to whatever sounds good to me. I don't know how low your main speakers go, but you can adjust the sub's crossover to whatever your speakers low point is. The sound is incredible. Go for it!

If you by-pass (defeat) the internal x-over in the sub, you'll be running both the main speakers and the sub full range. They will surely overlap for a few octaves. It is theoretically possible that this will work, but, as a practical matter, it will almost surely be a disaster.

Marty

To be clear,

You can certainly use ONLY the "high cut" function of the internal x-over in the sub to roll off the high end response of the subwoofer without using the "low cut" function of that x-over for your main speakers, per Sid 42. Many people report that this can work well.

Marty

I use Super Eclipse III's with an ACI Force XL sub. The Coincidents are great speakers that already go pretty damn low without a sub. I do what you describe and run a line-out from my pre to the sub, and a second line out to my amp. This arrangement took quite a bit of fiddling to get to work seamlessly, but trial and error with some help from ACI and various posts here have helped get it right for me. It really is a subtle effect with speakers that go this low, but it works quite well once sorted out. It is a matter of getting the combination of the low-cut, phase and volume just right. Room position also is quite important, but in my case I was very limited. With only a single sub I wonder if my soundstaging abilities are compromised slightly. Ultimately the presence of the sub should not be readily apparent in 90% or more of what you are listening to (at least that's the case with the music I listen to). I only notice the presence of the sub at the very deepest of passages and I do prefer it this way. I do not like when it intrudes too much into the bass range of the speakers, or if the volume is set too high.

Good luck.

Jax2,

I do not want to run the second line out to my amps as this takes away from running the system via balanced from my preamp and amps. I am thinking of what Marty just described.
The E III's do a decent job on most music but they are in a very large room (24 x 24) with a cathedral ceiling. A sub would help them pressurize the room a bit. Ideally a more capable sub would be the way to go but I had this in a closet collecting dust.