Subwoofer help: ACI, Von Schweikert, Martin Logan


I am once again looking for some assitance on choosing a sub that will be used primarily for 2 channel music but occasionally for movie watching. I am currently using Consonance Eric Grand speakers that I absolutely love but I know they cannot get the very bottom frequencies as they go down to 42hz.

They have very quick, tight, and focused bass response which I really enjoy. They are not bloated or boomy in any way. I am looking for a sub to really fill in the lowest frequencies.

I previously owned a Martin Logan Grotto and really enjoyed it but would like to spend less than its $1000 retail. The ML Grotto had a great deal of flexibility and fairly high WAF. I auditioned a Von Schweikert VRS1 in the past and think it does a lot of things very well. The new company I am considering is ACI and am looking at their Force XL and possibly the Titan XL. How do they stack up to the Von Schweikert and ML subs? Thanks for your help.
I use a pair of Depths to great success. I am considering upgrading to two Descents. the ML subs are hard to beat for the money. the Depth is by far the biggest bang for the buck in the line. They are small and produce lotsa bass in small to medium size rooms.
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The ML subs do have an onboard crossover. THere are quite a few lowpass settings, two highpass settings, a number of phase adjustments, and a 25hz level control.
Bob, the ML Depth does indeed provide (line level, not speaker cable) high-pass outputs, if so desired. At 40Hz, 70Hz, and "none". The "none" position is to daisy-chain another Depth onto the first. Then you use the high-pass outs on the last sub to go to your main amp.

My experience has been that I get best performance when I allow the main speakers, whatever they are, to run full range, and then bring in the sub just the slightest amount necessary, so that it's only noticed if it's suddenly turned off.

Naturally , phase, cut-off freq., and x-over slope must be properly adjusted to match the mains as well as the room.

The Depth also provides a second set of line level ins and outs to be driven by the LFE (low frequency effects) ouputs of a (separate) 5.1 processor. These inputs are signal sensing and mute the "regular" 2-channel inputs when you are playing surround material through a processor.
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