It took a while, but I like my CLS1's with Kinergetics SW800 subs (10 ten inch forward firing drivers in twin towers playing down to 16htz). Since the subs and crossover (and Compusound software) were desgined specifically for the speaker, integration is absolutely seamless. The SW800's are line sources (down to 200 cycles) like the CLS and are optimally positioned along side each panel. Fast and articulate enough to cross over at 100htz with 18db Butterworth high and low pass slope. Soundstage and imaging are significantly improved over CLS's solo. Mid bass and low end are out of this world. Minimal effect on the CLS's transparency. This is what one should expect from a system designed to work together. Check with the guys at Martin Logan -- they'll be happy to discuss the merits of this Mini-Statement set up. Know in advance that these subs can take some time to find. After several months of looking, I lucked out and got a pair that Martin Logan had.
Can't comment first hand on the Maggie/REL combination, but I can tell you that neither the REL's or Vandersteen subs worked with the CLS's. Not fast enough and the downward firing drivers just don't make it with this speaker, nor does placing subs anywhere behind the panels. Always running to catch up with the panels and muddying up the sound. Both companies make very good subs and their designs work with a wide vaiety of speakers, so this isn't a comment on the quality of their products, just the way they worked (or didn't work) with the CLS. If you don't go with SW800's just run the CLS's full range and dig the transparency thing that they do so well.
Can't comment first hand on the Maggie/REL combination, but I can tell you that neither the REL's or Vandersteen subs worked with the CLS's. Not fast enough and the downward firing drivers just don't make it with this speaker, nor does placing subs anywhere behind the panels. Always running to catch up with the panels and muddying up the sound. Both companies make very good subs and their designs work with a wide vaiety of speakers, so this isn't a comment on the quality of their products, just the way they worked (or didn't work) with the CLS. If you don't go with SW800's just run the CLS's full range and dig the transparency thing that they do so well.