Sub Woofer for Golden Ear Technolgy Triton 5

Sumiko S-9 or S-10. They are a Rel clone and ideal for music IMO. Integration is great and will make your main speaker sound bigger. I bought 2 S-10's from Paragon. They are on close out due to dropping the Sumiko name for Sonus Faber in the next ones made

Check out JL Audio. They should work fine with your speakers!
http://www.jlaudio.com/home-audio-powered-subwoofers

Depends on budget, and whether you want sealed or ported (expensive ported subs are very musical, even 18” ones). What are is your preamp/integrated/receiver?

Already purchased the 5's.
Any suggestions as to a sub that works well.
Thanks.

Why not purchase a Triton series speaker with the built in powered subwoofers?  The 3+ comes to mind.  It is the best way to do it as the bass to treble is seamless.

How bought one of the Golden Ear subs?