<p>The annoying noise produced by eVTOL vehicles is a big hindrance to their public acceptance. Numerous active and passive noise reduction techniques have been developed to cope with this issue. Phase synchronization technique is considered in the present research to analyze its noise reduction capability on different octocopter configurations, i.e., conventional, coaxial, and hybrid, with different rotor diameters and various vertical spacing in a coaxial configuration. The virtual blade method is selected herein for aerodynamic analysis, while aeroacoustics is performed utilizing in-house code based on the FWH equation to analyze tonal noise components. Relative phase angles are changed with 20<b>°</b> increments along the azimuth and associated overall sound pressure level (OASPL) values are calculated at a particular mic location. Based on these results, a detailed comparative study is conducted in terms of noise distribution on the acoustic hemisphere, noise directivity, noise spectrum, and acoustic pressure amplitude. Results demonstrate 0<b>°</b> and 100<b>°</b> relative phase angles producing maximum and minimum noise for all configurations with normal-size rotors. Phase synchronization is found to be most effective for coaxial configuration with 9dB noise reduction at 0.125R, 6dB at 0.5R, and 4dB at 1.5R vertical spacing. The conventional configuration shows 4dB noise reduction, while the considered noise reduction technique is not effective on hybrid configuration with normal as well as larger-diameter rotors. Noise is found to be maximum in the plane, hence noise reduction is also most effective in the plane with insignificant impact out of the plane.</p>