Totem Acoustic KIN Sub?

[Clark2]

[Update: This post is really less about the Totem unit and more about how best to hook up a sub-woofer (for $1K or less). Any advice on the methods and questions outlined below (given the constraints of my integrated amp) would be greatly appreciated!]


Has anybody tried this compact but application-flexible sub-woofer?

I have a set of old, but beloved, Beovox M 70's driven by a new Yamaha A-S501 integrated amp (line-level sub out with 100 Hz low-pass, but no separable, line-level pre-amp out/power-amp in). I'm straining the M 70's in my now-larger living room, so adding a sub-woofer may be the most cost-effective improvement. This one is highly recommended by my dealer, I can actually afford it, and it can also be hooked up several different ways.

I plan to route both speaker-level cables from the amp to the sub-woofer and then connect the main speakers to it's dual, speaker-level outputs. This should off-load the low base from the M 70's, allowing them to perform better at higher levels, while still getting good base response from the sub-woofer.

An alternative would be to connect the sub-woofer to the sub out of the amp and leave the main speakers connected directly to the amp, but this appears to have several disadvantages:
1) The M 70's will still get hit with the low base, making it harder for them to produce clean upper base/mid-range.
2) The 100 Hz crossover in the amp may not be ideal, and I'm not sure that the sub's crossover can be bypassed. If not, the two crossovers in series may not play well together.
3) If the sub's crossover can be bypassed, then I wonder if that also bypasses the (essential!) phase control on the sub. (This is the sort of detail that should be fully covered in the manual but is not.)
4) There's also the question of whether the amp's sub out comes off the pre-amp after the volume control. (Again, this should be covered in the manual but is not. Maybe it's standard?) If not, that would certainly make adjustment of the sub's volume necessary every time the amp's volume is adjusted -- a major pain.

Any comments or suggestions would be most welcome! -- Clark2