Linked to this thread is a beta version of a room simulation spreadsheet. The spreadsheet:
+ Allows entry of room dimensions, listener location and independent placement of right and left speakers
+ Calculates the location of the first reflection points along each of the side walls (for both speakers)
+ Calculates the speaker boundary interference frequencies
+ Calculates the room modes based on the dimensions of the room
+ Estimates the untreated room frequency response curve at the listener location
+ Estimates the T60 (time for a sound to decay -60db) based on the surfaces in the room (using Sabine's formula)
+ Calculates the Schroeder frequency for the room (room crossover frequency from resonator to reflector)
+ Calculates main speaker listening angles
+ Allows screen size and aspect ratio selection from a dropdown menu and calculates viewing angles
This was created to help me do all of these things as I'm designing a new home theater. There are various tools that do some of these things, but I didn't find one (that was free) that did all of them. I have done my best to validate the calculations, but there could be errors. The estimated frequency response curve at the listener is a rough estimate as I had to use linear interpolation for the location on the sinusoidal wave instead of a more precise calculation.
Feel free to use this for your own home theater adventures. Comments are welcome, but please be kind. It may not be perfect, but it meets my needs and might help others as well.
Spreadsheet Link Here
vb02 - Changed room width data entry to be direct, with secondary entry on listener distance from left wall.
vb10 - Added main speaker angle calculations. For home theater, viewing angle calculations along with a dropdown to select home theater screen size has also been added. The data entry was also simplified.