Spectral gain and loss (spectral gain&loss) of different-type photovoltaic (PV) modules, which are (1) amorphous silicon (a-Si), (2) perovskite (PVK), (3) CdTe, (4) CuInSe2, (5) multi-crystalline silicon, (6) single-crystalline silicon back-contact, and (7) heterostructure-with-intrinsic-thin-layer PV modules, is examined at different locations (Naganuma, Tsukuba, Gifu, Tosu, and Okinoerabu cities in Japan). Reference single-crystalline (sc-Si) PV module is utilized. It is revealed that average photon energy (APE) is uniquely used as an index of solar spectral irradiance regardless of outdoor sites, where APE of 1.59 eV represents airmass 1.5G spectrum with wavelength range from 350 nm to 1700 nm. APE is varied, depending on locations and seasons in a year, and it is the highest of over 1.59 eV (or blue-rich spectra) in summer. Average APE values in four-year period are 1.623 eV, 1.612 eV, 1.618 eV, 1.621 eV, and 1.652 eV at Naganuma, Tsukuba, Gifu, Tosu, and Okinoerabu cities, respectively, representing blue-rich spectra. Ultimately, spectral grain&loss of a-Si, PVK, and CdTe PV modules is above 1 (spectral gain) at investigated locations, implying that appropriate a-Si, PVK, and CdTe PV technologies with large bandgap outperform reference sc-Si PV technology in term of spectral response. Spectral grain&loss with different seasons is additionally discussed.