In this article, we present a multiband channel characterization at sub-THz. Three measurement campaigns were conducted in an indoor environment, for different frequency ranges: 125–155, 235–265, and 270–300 GHz, by exploiting a single (vertical) polarization antenna and performing only the azimuth plane. Line-of-sight (LOS) and nonline-of-sight (NLOS), given by human body obstructions and walls, are considered. From directional measurements, the omnidirectional power angular delay profile was extracted. Modeling of large-scale parameters and cluster study are presented.