Originally Posted by jpmst3
Yes, generally it is THAT bad.
Here are some guidelines
, note the first bullet in the list.
Rubbish. With a sub away from walls, you get less boundary reinforcement, but positioning is still beholden to the nulls of the modes for a given room. If you were to place it right in the centre of a room you would not excite either the first length or width mode, but you would get some reinforcement depending upon dimensions and construction. However LF reinforcement through boundaries may not be all the much, and may even be absorptive depending upon the construction of the room. U/G basement concrete bunker will get lots, 2nd floor timber and plasterboard will get much less. It's also dependent upon room size and the frequency in question.
Also having the sub in a coffee table will give you some gain, simply because there is less attenuation with distance as it's closer (assuming in front of the listening couch. A couch end table sub may not be all that different from a coffee table one as they will only be sightly different wrt boundaries in a large room.
Two smaller subs will give more flexibility in positioning and can help with averaging modes out across the LPs as per Toole etc.
KA, a couple of Shivas/Tempests in two separate enclosures that fit with your dimensional needs, sealed would be within your budget.