It is all about the ‘Room’, thinks Toole.

Just got the book and have read some of the parts that most interested me. Some of my take aways:

* Reflections, in particular side wall reflections, are not the enemy. They can add a sense of spaciousness to the soundstage. Toole pretty clearly recommends against using side wall treatment for stereo, in contrast to just about every room set up guide I've seen. I do think I was probably overdamping my own room with treatments.

* If you are going to put some sound absorbing material on the walls, use at least 4" of material. Othewise you get uneven dispersion since you are not absorbing enough low frequencies and are probably doing more harm than good.

* The idea of ideal room dimensions is oversold.

Except for a few places where he has "memos" in shaded boxes, the book is not written in a cookbook format that is easy to get straightforward recommendations out of. A lot of this stuff is somewhat subtle and not very cut-and-dried.

The book does seem biased toward multi-channel sound and home theater. I imagine that many sound engineers find stereophony old hat and are impatient with its many flaws.

That all jives with me.

I have my Walsh omni speakers within 2 feet of sidewalls in two separate rooms and this does benefit sound stage width. For more directional designs, more lively sidewalls might be needed for similar effect.

Some people do like their sound to come from in between the two speakers though.

Hi Buconero117,
I am nearly finished and have taken my time to 'digest' each section. I find it a facinating book and obvious tool that all a'philes should have.

The top topics that particularly interested me dealt with proving the conventional wisdom wrong. For example,
(1) the whole notion of treating lateral 1st reflection points on side walls was a real eye opener and one that must make many acoustical treatment company cringe.
(2) the fact that any treatment must work from the transition zone (i.e. Schroeder freq) on upwards so as to prevent unbalancing the direct frequency spectrum heard after the reflection. So absorbers must be 3"-4" thick minimum and diffusion should be 8"-12" depending on type is sage advice.
(3) many internet-based treatment companies sell bass traps that are of the resistive kind and they all seem to recommend that the products be used to "stradle the corners." Resistive bass traps (think GIK, RealTraps, DIY fibreglass) are most effective when the air motion is greatest which is one-quarter the wavelength which means pulling the resistive bass traps much farther into the room than "stradling the corner" advice would suggest.
(4) the notion that 1st reflections will deteriorate sound timbre was another falsehood unmasked. After considering delays and propogation loss from the reflected sounds, you won't hear the comb filter interferance.

A must read. Highly recommended.