I use a single Depth w/ my ML CLSs and it's amazing in all ways. Seamless and fast, organ music is real again. It's better (faster) than he Descent too, a conclusion shared by many people now.
However, I've heard the Summits, and I honestly can't imagine improving on their bass performance -- they really get down there, and with the same kind of refinemant as the Depth, and possibly a little more power too. If you are using your Summits with a HT capable system, you might want a sub w/ a 15" driver for room-shaking soundtrack effects (which I'll bet the Summits can do too) but definitely not for 2 channel.
Just as an aside in case you're amp shopping: With the earlier ML hybrids, you had to use a ss amp if you wanted good bass, and accept the way the stat panel sounded (a little edgy) or bi-amp, and using a tube amp for the panel. With the Summits, you can forget about needing a ss amp or bi-amping (since they have their own ss amp for the bass) and drive them with a really nice tube amp
However, I've heard the Summits, and I honestly can't imagine improving on their bass performance -- they really get down there, and with the same kind of refinemant as the Depth, and possibly a little more power too. If you are using your Summits with a HT capable system, you might want a sub w/ a 15" driver for room-shaking soundtrack effects (which I'll bet the Summits can do too) but definitely not for 2 channel.
Just as an aside in case you're amp shopping: With the earlier ML hybrids, you had to use a ss amp if you wanted good bass, and accept the way the stat panel sounded (a little edgy) or bi-amp, and using a tube amp for the panel. With the Summits, you can forget about needing a ss amp or bi-amping (since they have their own ss amp for the bass) and drive them with a really nice tube amp