Sub options with purely music in mind.

VANDERSTEEN

they are VERY different with multiple drivers .... Convinced me enough to buy one.

googke the reviews (they make two different models - a HT model and a pure audio one) .... Both are great but it looks like you are looking at the latter Y/N?

See background reading article 

http://ultrafi.com/why-everybody-needs-a-good-subwoofer/

Second the Vandersteen (full disclosure, I'm currently selling a 2Wq but ONLY because I replaced with Vandersteen 5s which have built-in subs). You do need to have separate pre- and power-amplification in order to place the crossover between the two, but this sub is built specifically for speed and tunefulness.  You can tune the Q (hence the "q" in the model designator) for your space and taste.  These subs just get it right--used mine in conjunction with Magnepan 1.6QRs and it was a killer combo.

I am currently using a single JL F112. I have until June to get full purchase price (3,150) on a trade up to a Velodyne DD+18. Listed at $5,800. So I'm looking at around $2,700 to upgrade, or can pick up another used JL F112 for around $1,500-1,700. I have read many benefits of the use of two subs. Wondering if anyone has any experience with the DD+ series, or going from one, to two subs in the same room. Thanks

A few months ago I was ready to place my order for a pair of JL Audio F112V2's and instead ordered a pair of F113V2's, given the size of my listening room.  In the end, I probably would have done just as well with the F112V2's (and saved a bit of cash).

I used to have a single Velodyne DD12, which worked well for me for several years, in a smaller listening room.

I must say, I think the JL Audio subs just seem to have more "detail".  Also, upgrading from one to a pair has been worth the expense, as I have all digital source, and experience the visceral benefits of having bass come from one channel, when the instruments are positioned that way (like a symphony orchestra).

I always thought the Velodyne's were great subs, and they are, but the JL Audio's seem to be a cut above.

ejr1953, Thank you. I was kinda leaning toward the dual sub option, but my dealer insists I would be happier with the one 18. Of course he doesn't make anything if I pick up a second hand partner to my F112. I have the V1 model, have you had any chance to compare the difference between that, and the new version? Thanks.