Particle velocity histories and electrical conductivity distributions are compared in three detonating high explosives: cyclotrimethylene-trinitramine (RDX), cyclotetra-methylene-tetranitramine (HMX) and pentaerythritol tetranitrate (PETN) at various initial density from loose packed to strongly pressed. The correlation of the region of high conductivity and the chemical reaction zone is confirmed. The conductivity reaches a maximum within the reaction zone, and becomes much lower afterwards. The conductivity peaks are quite distinct in contrast to the velocity profiles which do not exhibit any peculiarity near the expected Chapman - Jouguet state. (C) 2019 The Combustion Institute. Published by Elsevier Inc. All rights reserved.