Acoustic treatment question: do you agree with Dennis Foley that $46k to $65k is required?

I would say that it depends on the specific room. If you set up your system in a bedroom, apparently a large bed makes a great bass trap. 

It is a matter of doing things right.  I know of a system where the dealer removed much more than $50k in treatments from a client's room to get it to sound right (there was a whole room on the side that stored the massive quantity of tube traps, etc).  I heard a dealer room that had been specially designed and treated by "experts" that sounded terrible (this was during the live-end, dead-end era of treatment).  Among the better rooms I've been in have been rooms with very minimal treatment (mostly decorative wall hangings, book cases, etc).  In sum, among serious setups, I've heard more rooms that sounded dead from overtreatment than I've heard rooms that were undertreated.  

By far, it is MUCH more important to get the placement of the speakers right.  This is actually much trickier that most people think, and one can experiment for a really long time before the right placement of speaker, listening chair and furnishings is accomplished.  But, when it is finally achieved, the results are usually better than one gets by stuffing the room with absorbing panels, diffusers, etc.

@larryi you are correct. Start with an untreated room and set up the speakers properly. I have used several different methods, but the one that has worked best for me is the Wilson Audio set up guide using your actual voice to determine the preferred location of your speakers. The mathematical guides are ok for a starting point but they don’t consider the other variables such as existing furnishings in a room. Add room treatments slowly such as bass traps and first reflection point absorption. It’s easy to overdue the room and I prefer diffusion myself.

It is a matter of doing things right. I know of a system where the dealer removed much more than $50k in treatments from a client’s room to get it to sound right (there was a whole room on the side that stored the massive quantity of tube traps, etc). I heard a dealer room that had been specially designed and treated by "experts" that sounded terrible (this was during the live-end, dead-end era of treatment). Among the better rooms I’ve been in have been rooms with very minimal treatment (mostly decorative wall hangings, book cases, etc). In sum, among serious setups, I’ve heard more rooms that sounded dead from overtreatment than I’ve heard rooms that were undertreated.

The first part of your post make perfect sense...

Because anybody who treat a room must use his EARS, be him an acoustician or not, to know when to stop and to know what material device to put and where to put it...

Any room must be tuned by our ears or the acoustician ears, not with only an equation, or an electronical equalizer.... The human EARS ca perceive GLOBALLY whow the room sound....Nothing else can.....Id the acoustician dont use his ears correctly it is too bad.... 
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And yes it is important to put speakers at the right spot in the room and very precisely so...

BUT it will never replace by itself the almost always necessary passive treatment, the right balance between diffision/absorbtion/ and reflection... Especially in an acoustically complex content , geometrically, and topologically in a complex small irregular or small square room...

Most people also ignored the necessity for an optimalization of the relation between the room and the specific speakers with an active mechanical acousticl control by Helmotz method...With it you can create various different new pressure zones in the room and greatly modify the way the sounds is perceived at will....

By far it is MUCH more important to get the placement of the speakers right. This is actually much trickier that most people think, and one can experiment for a really long time before the right placement of speaker, listening chair and furnishings is accomplished. But, when it is finally achieved, the results are usually better than one gets by stuffing the room with absorbing panels, diffusers, etc.

I am certainly not suggesting that treatment is important and helpful.  I am merely cautioning against the "more the merrier" approach or any kind of formulaic approach to treatment.  It is really a quite painstaking procedure that is quite hard to do because of the natural bias (hopefulness) toward thinking that any given addition is improving matters.  I don't know of any really good procedure except careful trial and error.  

A friend added some modest treatment to a small listening room (corner traps and diffusers, and absorption at the first reflection point).  An industry expert that has heard thousands of different rooms around the country is a friend of his that came over to help out with the room.  We were told to close our eyes while the expert performed some alterations which we then commented upon.  To our surprise, the sound improved when the first reflection point absorbers were removed.  I had thought that this was a basic thing that almost always helps, but, he said that while it usually helps, this is not always the case.  The next surprise was when he leaned against the side wall to damp some resonance--again that turned out to hurt the sound (certainly not my expectation).  The best thing for improving the sound turned out to be opening a closet door at the back of the room which acted as a sort of bass trap.  The point of this is not that this or that treatment works, but that it is nearly impossible to make any sort of generalized recommendation--proper treatment involves careful listening and application of products or practices after trying them out.