Subwoofer Advice

I am running a pair of Martin Logan ESL 13A speakers (24-23,000 Hz). I would have thought with two 10" woofers there would be more bas (the base level dial on the rear of the speakers doesn’t seem to cut it either).

In the past I had a pair of ML Spires (29-23,000 Hz) with only one 10" woofer that had so much base, I sold my pair of ForceField 30s. Not the case with the 13A’s.

I don’t have a lot of room, maybe 16" or so square and I was wondering about a pair of SVS Micros. Do you think they would complement the 13As or do I need something bigger?

Martin Logan has come out with a few new subs lately; do you think I should keep in the ML family?

Hoping to come in under $2K, so used is fine. Thanks all!

I should also mention I’m limited on space so placement would likely have to be on the inside or the outside of the main speakers (same back wall).