I have been looking into creating the sound of a rainbow, (having taken four proposed ranges for each colour band, translating Terahertz to Hertz and taking the mean average mid-points of each colour to the closest natural note), I have arrived at the following set of notes:
445 Hz Fourth A
496 Hz Fourth B
524 Hz Fifth C
560 Hz Fifth D flat
630 Hz Fifth E flat
685 Hz Fifth F
744 Hz Fifth G Flat
I have built a working seven-string harp/lyre thing, designed for acoustic Guitar strings with an approximate resonating length of 56 cm/22".
I understand enough to know that there are pitch/tension calculations involved, but I have no idea of how to do these calculations.
If anyone feels kind enough to do the maths for a music beginner I would be very grateful.