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Old 05-02-2007, 12:10 PM   #25
Bubbagump
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Join Date: Nov 2006
Location: Columbus, Ohio
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Thanks on the stands. Me thinks there is a trip to the lumber yard in my future.

Looking at ModeCalc, we want to use the axial modes... so looking at the table, which is that? They give 3 columns (one each under length, width, and height) and which numbers should we care about most?

EDIT: Dah, it was buried on the ModeCalc page. It seems modeCalc ONLY gives axial modes:

Quote:
When viewing the results look for an even spacing of the modes regardless of their color (good), and also look for multiple modes that occur at or near the same frequencies (bad). Also compare the ratios of the dimensions you entered with the recommended ratios, and compare your room's volume with the recommended minimum of approximately 2500 cubic feet or 70 cubic meters. Top

To make it easier for you to identify modes that are close together ModeCalc draws those mode lines taller, which simulates the larger response peak that occurs. The normal line height is marked with a thin gray horizontal line. When two modes are adjacent, or at least close, both lines are drawn taller. The closer the modes are to each other, the taller the lines appear. This also lets you identify modes that fall on identical frequencies. ModeCalc draws all the lines for one mode, then the next, and the next. So if several modes are at identical frequencies one line will hide the other. If you notice that an isolated line is higher than usual, that means there are at least two modes at that same frequency. You can then use the Frequency Table display to see them all. Also note that modes naturally become closer at higher frequencies. Therefore, having taller lines toward the right side of the graph is normal, and does not mean your room will really have that rising frequency response.
Any suggestions on speaker placement? If I remember correctly, you are supposed to put them so far from walls (38% something or other) and then your listening postion moves somewhere. Sorry to ask so many questions, but I think they are related to the original question and you are very knowledgable... I very much appreciate your explanations.
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Last edited by Bubbagump; 05-02-2007 at 12:54 PM.
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