No crossover. Just add subs. Buy more, not bigger. Three pretty good subs is better than one really good sub, in other words. The key to really good bass is lots of subs spread around in different locations so that they all have different bass modes at different frequencies and locations. This results in much smoother bass than you can get from fewer subs. Do a search for Swarm subwoofer system or distributed bass array, and pay attention to the guys like me and Tim who actually have done this. https://systems.audiogon.com/systems/8367
Notice this is five subs, three different types, in random locations around the room. The bass is phenomenal! And Moabs already have really good bass, but with DBA its even better.
Listening at moderate volume you will be able to adjust yours to the level that works best for the volume you care about most. It will be sort of like a loudness control. This won't work nearly as well with one or two subs because the bass is lumpy but with a DBA its so much smoother, so much more articulate and tuneful you'll be able to set it higher which will be perfect for lower level listening. If you turn it up real loud you will have too much, and in the long run you will find the happy balance.
You won't need bigger right now but long term might be a different story. Notice mine are mostly 10" and my room is big 17x24 so its not like you need big subs, but if you can get a deal or will be in a bigger room some day then maybe buy for the long term. Main thing is to get to where you've got at least four.
Notice this is five subs, three different types, in random locations around the room. The bass is phenomenal! And Moabs already have really good bass, but with DBA its even better.
Listening at moderate volume you will be able to adjust yours to the level that works best for the volume you care about most. It will be sort of like a loudness control. This won't work nearly as well with one or two subs because the bass is lumpy but with a DBA its so much smoother, so much more articulate and tuneful you'll be able to set it higher which will be perfect for lower level listening. If you turn it up real loud you will have too much, and in the long run you will find the happy balance.
You won't need bigger right now but long term might be a different story. Notice mine are mostly 10" and my room is big 17x24 so its not like you need big subs, but if you can get a deal or will be in a bigger room some day then maybe buy for the long term. Main thing is to get to where you've got at least four.