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.
If your main is quick, and you can stretch your budget 2-3 hundred dollars, you'd be well advised to go with a (used) ML Depth.

You didn't mention your room size, but you should only need one, and placed right between your mains. I think the "Balanced Force" driver placement is the best sub design innovation in years.
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.