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		Exponential / Hyperbolic Contour Calculator by James Melhuish This applet calculates a table of figures for an exponential / hyperbolic horn showing distance from throat, radius, effective square side length, cross sectional area, and contour width (for your given horn width in a parallel sided horn). All dimensions are in centimeters (cm) and are precise to one tenth cm. Throat area (cm2) — decimal (for example: 70, or 70.35) Flare freqency (lower frequency cutoff) (Hz) — decimal Size factor (1 for mid or high frequency front horns, bass horns: 2 for center of room, 4 for against a back wall, 8 for corner placement) M (the degree of hyperbolic influence — 1 for pure exponential, less than 1 for exponential/hyperbolic, 0 for catenoid — decimal Desired width of horn cabinet (cm) — decimal Then click Calculate! You need Java 1.1 (Netscape 4 or IE 4 or later) to run this applet You can copy this table of figures to the clipboard and paste it into Excel or 123 or other spreadsheet program in order to print or manipulate the data. Notes: You will find that the length of a horn, especially a bass horn, quickly gets long and the mouth gets very large as you lower the Fo. If designing a bass horn, you might want to shorten it so the horn is a more manageable size. One acceptable method is to use a quarter wavelength of the fc as the minimum length. For throat = 70 cm2, fc=35 Hz, size factor = 4, this results in a horn length of 232 cm and mouth area of 1422 cm2, a reduction in length of 60% (possibly a bit too much shortening for really good sound). Top