Rhythmic or Hsu

Thanks everyone for taking the time for the input and responses.

Still want to buy something...

Here, I wrote this for you:

https://speakermakersjourney.blogspot.com/2020/04/how-to-not-buy-subwoofer.html

My house is full of subs, nothing matches. It's time to get coherent.
I've got a Velodyne "12, Earthquake "15, two Vandersteens that I could never get to work, and two Epik "12 subs that were OK.
It's time to get serious. Music only.
Please help me save money.

Seriously? This is almost too easy. rbshafer, you are there. All you do, hook them all up. They do not need to match. Mine don't! 
https://systems.audiogon.com/systems/8367
b_limo is right, search DBA/Swarm. You've got four perfectly good subs. Six, if you connect the 2 Vandy's to something and run them passive. But even just the four you have will work great. 

I know, everyone thinks speakers have to match. Well, speakers yes. Subs no. Which you have plenty. Don't cost nothing. What do you have to lose? Just when you get done being amazed please come back and let us all know. There's still a few haven't figured out DBA really does work.

Just curious, what wasn’t working with the Vandys?  They’re supposed to be great subs, especially for music. 

I've owned both, but my Hsu experience was a couple of generations ago, a VTF-3 MK III. I still own one of their MBM-12 mid bass modules that I use for movies.

I don't think they are made as well or sound as good as rythmik, but maybe they've gotten better. I would buy rythmik, svs, or psa before Hsu. I currently have a rythmik f15 that I use in my office system and two f25s (and 2 svs sb13 ultras) in my main system.  The ULS-15 is the one I'd look at if I was to consider another hsu sub.

Que swarm or dba setup...