The Studio Room Calculator

There are four primary parts to the Calculator:
	The Axial Mode display uses the room's dimensions to calculate room resonances and check for out-of-spec conditions.
	The Absorption Tables calculate absorption of many common materials.
	The RT60 Graph displays the summary information in a simple-to-understand format
	The Miscellaneous section keeps some handy information easily available.

To use the Calculator to calculate the optimal room proportions:

1: 	Open Studio, the combined workbook file - you must have Excel 4.0 or later for this program to operate.
2: 	Enter the room's projected length, width and height into the fields noted. Area and Volume will be calculated.
3.	Calculate the node list with the 'New Nodes' macro. Press Ctrl-N to run it, or select it from the Macros menu.
4.	Examine the Sorted Nodes carefully. 
		Nodes closer than 5 Hz will be marked 'Close'
		Nodes further apart than 20 Hz will be marked 'Wide'
		Nodes less than 1 Hz apart will be marked 'Zero'
	All of these conditions should be minimized. Strive to find a set of measurements that create smooth transitions between the nodes.
5.	If the numbers are not to your liking, start again from step 2 until the numbers look good. If no set of numbers looks reasonable, you may need to select a different room, or go to heroic lengths to properly condition the room.


To use the Calculator to calculate the optimal absorption:

1:	Determine the desired T60 (the actual value for small rooms is typically between .6 and .85 for music and between .38 and .62 for speech - 	volume of the room determines where the actual numbers lie, room volume between 3000 and 15000 cu. ft. was used to generate these figures.)
2.	Begin by entering the area of the original floor, walls and ceilings into the appropriate spots on the worksheet. For example, my floor was 	painted concrete 20' x 19' in area, so I entered 380 into the 'Painted Concrete' area cell (C73 on the original sheet.) If I were still examining room 	size options, I could enter the Formula '=J2' in the cell - this gets the result of the Floor calculation from above. I could also enter '=20 * 19' 	directly into the cell and Excel would calculate the result.
3.	Add in the wall materials (usually sheetrock) again either directly or from the numbers above. This will give the initial conditions of the empty 	room.
4.	Add in the studio furniture - this is difficult, as there are no 'furniture' selections. Try to estimate how an item may be like one of the elements.
5.	Now comes the art part! The large graph shows the current state of the absorption by octave. Locate materials you wish to consider adding to the 	room for sound conditioning.The small graphs to the left of the material can help determine what this material will do to the sound of the room.
6.	Estimate the area of the material you wish to add (how about if I add 12 sq. ft. of 2" unpainted Sonex?) and enter the number into the 'Area' box. 	The system will recalculate the absorption values and alter the graph to show the new figures.
7.	The goal is to get the red Avg time to line up approximately with the green triangle (desired value) while the yellow-dotted line aligns straight 	across the graph. Add or subtract materials until this is achieved.
8.	NOTE: All these values are approximate! Don't waste time trying to get the calculations exact, they aren't accurate enough (and even top audio pros don't agree on what they should be!