The essential problem with all of the frequency correction stuff is that they can only attempt to correct at a very specific point in the room and they have to do so by using equalization curves (sometimes severe ones) which will often create their own problems (phasing issues at the EQ boundry points).
It's largely an issue of room shape, physical dimensions and the nature of the surfaces in the room.
My studio area is in the basement of my house. Bought it new and I did all the finish work myself (started off as just a big empty room with concrete floor and open cieling joist's). It was split into a mechanical room, a small office, a guest bedroom and a home theater area (which I've now taken over as the studio).
When I designed the home theater area, I used a room mode calculator to figure out what the resonant mode frequencies would be and where they would be located (this is a critical thing...simply saying that the room has a resonant mode at 64 hz is useless...you need to know WHERE in the room that mode occurs).
Here's a link to the home theater site where you can download the excell spreadsheet...
http://www.hometheatershack.com/forums/ ... erter.html
The nice thing about this spreadsheet is that you can enter the listening position, and it will calculate the resonant modes that will exist, at that position, as well as their intensity. This gives you some idea of what you need to work on.
Here's another link to a site that has a real wealth of solid, technically sound information about acoustics for music production rooms. The guy also provides lots of info on DIY methods of dealing with room acoustic problems. Some easy to build bass trap designs etc.... He also talks a bit about some of the concerns with certain makes of rockwool (vapors of some sort...I dont recall the specifics but I think I recall that he lists brands that do not have this problem "Roxul" being one of them).
To save you some time, here's another link for a good source for the mineral board and batt's that you can use to make acoustic treatment panels.
http://www.atsacoustics.com/page--Selec ... l--ac.html
A final point to keep in mind too, many folks get the idea that all they need to do is absorb bass and dampen reflections. The treat the heck out their room and end up with an anechoic chamber that just sounds completely dead. Making good use of refractive panels is important too. For example, if you're working in a converted bedroom, you probably have a wall not to far behind your mixing position. While you could put up damping panels (Auralex etc...), oftentimes, the best thing to put there is a book case full of books. The book spines, sticking out at various depths, can make a great refractive surface thats very random in it's sounds reflection characteristics. It looks good and it's functional too.
Hope this helps.
Studio system-i5 750, Intel X25 SSD, 3 Raid 0 arrays (2 for streaming sample players, 1 for projects), 16 gig ram, Win7 Pro 64 bit, RME Multiface and Digiface, Cubase 4.5 and C6, NI Komplete 7, Omnisphere, Trillian, EWQL Symphonic Gold/Colosuss, BFD 2, Jamstix, Waves mercury pack, lots of mic's....yada yada yada.... see my equipment list at...
Reference Point Recording Equipment List
Reference Point Recording