Velodyne DD-series subwoofer


I am currently deciding between a Velodyne DD-15 or Velodyne DD-18 subwoofer for my home theater system. My room size, not yet confirmed, will likely be at least 15 x 20 feet and possibly larger if there is an adjoining kitchen and/or dining area (although there may be no adjoining area at all, so the room may only be that size or even a bit smaller or larger). The room height would be about 9-10 feet. I have a very good deal on all the Velodyne DD subwoofers, so the price difference between the subs are insignificant.

Music/HT is about 60/40.

Is there any reason NOT to get the 18" subwoofer? Is it possible it would be too large for my room? What is the smallest room for which the 18" sub should be used? How would two 15" subs compare to one 18" sub? Are two 18" subs feasible, at least for future upgrades?

I live in an apartment- it it possible to use an 18" sub without disturbing the neighbors? How about the 15"?

My equipment currently includes B&W804s and B&W HTM1, and will likely be using a Bel Canto 3-channel amp to drive them. pre/pro/surround amp is Yamaha RX-V1500, with B&W DS7 surrounds probably.

regards,
Brandon
no_slouch
Great subs, the determining factor should be real estate. How much floor space do you want to dedicate. I have a room similar in size and have the DD-12 and it does just fine. If anything I might recommend, since the price is right for you, get 2)DD-12s you would get much better imaging and distribution. Either way you will love your DD Velodyne.
If money and the size of the sub are not an issue then just go with the DD-18. If size is an issue then go with the DD-15, you will probably only be giving up a few db's of headroom and a couple hz of extension. I have a DD-15 in a 21 x 15' room with and 11' ceiling and I have more than enough quality and quantity of bass to satisfy me for music and HT. Dollar for dollar they are a much better value than a REL.
If you are in an apartment then decouple the sub from the floor to prevent shaking your neighbors physically. Try some Aurio's under the sub, and mass load the top with some lead shot (25lbs #6)

DD15 or DD18? Awesome problem to have, I basically couldn't use my sub in an apartment before decoupling the sub. Invite your neighbors over during movie time..
Expect the police soon; thereafter. Maybe you have a movie they haven't seen?--This is a joke,right?????