I am thinking about purchasing an armoire and placing my Eosone powered or Bose passive subwoofer in it. Can anyone think of any issues with keeping it inside the armoire?
Make sure the sub is front firing and front ported. You don't want any energy going into the cabinet. If the armoire has a door, it will have to be taken off, or remain open. The last option of a mesh insert is not very good.
When you put the sub in there, you will have to stuff all the open area in the rest of the cavity with batting. Any open air in the cabinet will resonate at a certian frequency throwing the sound of the sub way off.
If you can do all that, it will be decent. But the cabinet will still probably rattle, and create resonances that will mess with the sound of the sub.
I have put my sub inside an entertainment unit. It worked very well. The entertainment unit is very large and very well built. The bottom sections on both the left and right side, have doors that can be either wood or fabric. I used a front firing sub. The only reason I moved it out was my controls (volume and crossover) are on the back. It made it hard to adjust them (blind).
Yes, you will effectively be putting a cabinet inside of a cabinet. If you must hide a sub, don't put it in an enclosed space. Put it behind a chair or a sofa so it can do what it was meant to do...move air.
Make sure the sub is sitting on something that will either dampen or absorb vibrations, such as Vibrapods.
I have a Pinnacle SubSonic, which is a dipole design, sitting on Vibrapods and firing front and back inside a corner cabinet. I cut 3 large (2") holes in the back with a hole saw, and when I do serious music listening I leave the front cabinet doors open. The bass is excellent and the cabinet does not rattle one single bit.
But even with the cabinet completely closed (it also houses a 32" TV as well as integrated amp, DVD, VCR, and cable box) for background music, the bass is still nice, tight and clean although not quite as deep.