Spectral montage for our set of models at 2.1 d (left panel), 25.7 d (center panel), and 97.8 d (right panel) after explosion (i.e., around the time of bolometric maximum). Each spectrum has been normalized and shifted (a tickmark gives the zero-flux level for each spectrum). The vertical dashed line locates the rest wavelength of Hα and reveals the blue shift of the emission peak at earlier times and higher explosion energies.