Use of subwoofer with bookshelf speakers

However...I believe Vandersteen( and others) recommend crossing over an octave higher...so full range speakers would be x-over at 80hz...most speakers are -3db down or more at their LF cutoff point...thus the rationale for x-over higher...and anything above 80hz is usually directional in nature...hence the full range recommendation...

I think Vandersteen's approach calls for a gentle-slope crossover between mains and sub(s) - maybe even first order, I'm not sure. Nothing wrong with that, you just gotta have the right speakers for it. Well okay one possible drawback is that you have to keep the sub(s) near the main speakers, because they will still have audible (and localizable) output well into the upper bass region. Obviously not an issue if you plan to place the sub(s) near the mains anyway.

Duke
dealer/manufacturer.

There are so many variables--you simply have to experiment with different c.o. frequencies and find what works with your situation. That's the only way to know.

I agree with Bob Reynolds here. You have to look at the bass rolloff characteristics of the Canalis to correctly match it to a subwoofer. He's also correct about the Vandy's crossover slope of 6 dB/octave. Here are the specifications.

One thing the Vandy has going for it is that it uses 8" drivers, giving it a higher ratio of flux density to diaphragm size, which is better both for transient response and for less cone breakup. With a 5" woofer, you want a subwoofer with great acceleration--transient response--to keep up with the 5" woofer. The Canalis 5" woofer is aluminum, so it would be particularly fast and rigid and need a fast sub to keep up. Not too many subs are great at both matching to mini-monitors for music and also having the bass extension and dynamic range for home theater. It appears that the Vandersteen was designed to cover both applications, and the gentle 6dB slope should make blending it with the satellites a bit easier.

If you didn't already have the Vandersteen (I assume), I'd recommend you get a pair of small, sealed subs. I match a pair of (now discontinued) Mirage MM8s with my Mirage OMD-15s. The MM8s are 9" cubes housing an 8" aluminum driver augmented by two 8" aluminum passive radiators. They don't go very deep, but they are very easy to match up musically with bass-shy speakers. They have lots of power and a crossover that can be adjusted from 50 Hz to over 200.

Although the Mirages are discontinued there are several good small sealed subs with similar configurability. They're easy to blend with decor and match up with small speakers well, but they generally aren't designed for room-filling 20Hz bass as the Vandersteen is.

Johnnyb, I like what you say about the relationship between the bookshelves and sub, especially as regards mating the acceleration of the fast fast 5" woofers in the bookshelf and relatively fast acceleration of the Vandersteen sub speakers. This speed was my reason for buying this subwoofer years ago, in the first place. The other responses are valid and much appreciated but I, at least, have a bit more confidence that the Vandy will work out as I very much enjoyed this sub when it was in use with my Focals and I would like to minimize expenses as much as I can. It will be awhile before I can justify/afford the speakers I want so I have time to kick this around for a bit. Thanks.