The Jl makes the Vandy's finally work. I hate to say this because I own a pair of Model 5a's and 2 ce sig's and I never in a million years thuoght I would need another sub for the Vandys but a got a JL 13 and it KILLS the subs in the Model5a's. Just one Jl sub makes the 5 sound wonderful- It get that little bit of detail that everyone out there(and yes you know) that lots of audiophiles say they love Vandy's but,they need a little more detail- they are too soft-you go on the discussions on Vandersteen and there is several people that have sold there Vandays (because the lack of upper detail) and the built in subs are not tight. I called Audio Connection and one of there employees(no names) even told me the B&W 800d kills the 5a's on pure detail. The JL Audio makes the Vandy sing.