We report the results of the effect of static pressure on the Raman spectrum of TATB up to pressures of 160 kbar and deuterated TATB (DTATB) up to pressures of 65 kbar. Both these solids are found to be remarkably stable to high densities. We observe unusual pressure dependence of the δNO2, νC-N, and νN-O modes and attribute these changes to variation in NH2/NO2 coupling as the pressure is increased. Both of these aspects of TATB may be important in contributing to the insensitivity of TATB to shock-initiated detonation. We also find that, unlike at ambient pressures, TATB is quite insensitive to photolysis when exposed to static pressures exceeding 15 kbar, indicating that photolysis of TATB involves a positive activation volume. In addition, we present inelastic neutron scattering data as well as some assignments of TATB and two related substituted anilines, p-nitroaniline and p-chloroaniline. These clearly demonstrate the strong vibrational coupling between NH2 and NO2 groups.