To synthesize a desired sound at base frequency Hz, find the frequencies of the peaks of the recording with the closest base frequency to . Alternatively, other search methods can be used. For example, find the recording with the closest base frequency to that is not greater than , if there is such a frequency. Generate sinusoids at these frequencies at desired lengths and sampling frequencies. Apply to Eq. (1) with output as , and scale (e.g., multiply) each value from the generated sinusoids by . Then simply add the first, second, third, etc. value of each wave together to produce the output wave.