I'm trying to generate a sawtooth wave using the IFFT. I can do this successfully by first performing an FFT and then putting that analysed spectrum into the IFFT, however I would really like to be able to write a UI that enables me to draw the bin magnitudes and generate a spectrum from that. I have been partially successful, however the waveforms don't look quite look/sound right even though the spectrum input is per the formula for synthesising a sawtooth wave.
My question is how do I generate a spectrum array of complex values for an IFFT when all I have are the magnitude values?
I know that bin 0 and 1 are zero valued. I've been trying to render the wave by only calculating the magnitudes and phases for the significant bins containing the non zero magnitudes. Am I able to put white noise in the remaining magnitude bins and then calculate the accompanying phases at the centre frequency? Thanks in advance for your contribution.
sorry for the clear answer: Not at all. Your values need to be complex, so you must offer the user a method to input complex values. Letting the user specify the magnitude is only offering half of the freedom she/he needs to specify arbitrary wave forms.