Starting design from scratch - room design

Well technically speaking the ideal room has four unequal sides, so that the standing waves issue in most rooms won't happen. However I realize that may not be possible. Personally I kinda cheat and use a Receiver by Pioneer, it comes with a microphone and tunes itself, standing wave adj., phase control, and auto e.q. just to name a few. I know this sounds like sacrilege to a lot of Audiophiles, but given your budget this may be right up your alley. The Pioneer I use is a Model SC-61. I got it online for just under $800 dollars, with a warranty and shipping. It has several HDMI inputs, six I think. It excepts any Fiber Optic or Coax Audio Input and it also has the ability to Bi-Amp your Front Monitors.

As far as room design goes, I know when I built my office into one side of my garage, I kept it very simple.... you know K.I.S.S.or Keep It Simple, Stupid. Anyway I used 5/8" sheet rock with some reinforcement spread around the ceiling. I used insulation that is Alaska spec for the walls, which is 13 inches thick. I shoved that into the four inch wall gap. This was done to keep the walls in compression (like Hover dam), thus eliminating vibration.
The garage door was a different story, I started by inserting foam panels in the garage door recesses. Then I sealed up the guide tracks on either side using foam panels and expanding foam. The idea here is to get it close but with enough clearance to keep the door operational. Making the sound go around a few corners can have decent results for sound/temperature control.

As for the software question....... Myself? I don't use it much, have a medical condition known as Synesthesia, a crossing of sensory perception. Or in my case, I can see sound waves traveling around like ripples in the water. So I tend to stay away from software unless it saves me a bunch of math. I would recommend a book like the one I read before building my sound room.......called, Master Handbook of Acoustics fifth edition by, F. Alton Everest & Ken C.Pohlmann

Good luck, I hope I helped.
Andrew
Synesthesia Studios

You are not searching for a null point calculator, which is a simple program where you enter a room's dimensions and it spits out what are the worst offending null point frequencies.

Even if you minimize the worst nulls that still doesn't mean you won't need room tuning or accessories.

The size of the room and its construction determines the level of clean bass energy you can develop, but does nothing about high frequency waves energy which can be bounced back off of hard reflective surfaces.

A good room will be of the correct proportions and will use panels to diffuse or absorb energy, bass traps to limit the standing waves which will still develop in the corners, possible electronic room correction and passive room tunning with devices such as Shakti Hollographs and Resonators.

So if you think you can save thousands of dollars in room tuning, just by getting the structure right you will have another thing coming.

In fact I can make more of a profound difference in the sound quality of a room with tube traps, shakti's and ASI products then with very expensive rooms done by some of the big room tuning services out there, I have heard some of these mega expensive rooms and the music was devoid of life.

Another mistake is using too much absorbtion, diffusion is far better.

I bought a bunch of books on the topic, and by far the most helpful was Premium Home Theater by Earl Geddes (principles apply to stereo too). He goes through theory and construction techniques to address everything from low bass to high frequencies in a relatively easy-to-understand fashion, and unlike most books he mentions specific products to use that I found very helpful. Constructing a room like this should help reduce the need for additional treatments although you'll probably still need/want to use some to fine tune. I agree with Audiooracle that many professionally designed rooms sound overdamped an acoustically dead, and Geddes also addresses this in his book. Best of luck.