# Additive & Spectral: IFFT Synthesis

The calculation of single sinusoidal components in the time domain can be very inefficient for a large number of partials. IFFT synthesis can be used to compose spectra in the frequency domain.

*Main lobe kernel for* \(\varphi = 0\)

*Main lobe kernel for* \(\varphi = \pi/2\)

*Main lobe kernel for* \(\varphi = \pi/4\)

*Main lobe kernel for* \(\varphi =c3 \pi/4\)