We present a comparative study of density of states (DOS) and group delay times for a one-dimensional (1D) coaxial photonic crystal made of N cells attached horizontally along a waveguide. Using the interface response theory of continuous media, we derive exact analytical expressions relating the DOS and reflection and transmission delay times. We demonstrate analytically and experimentally that the reflection and transmission delay times for a symmetric system are not equivalent when we take into account the dissipation in the cables, and the DOS presents a different behavior in comparison with the reflection delay time because of the existence of additional enlarged delta peaks in the latter quantity that cannot be detected without loss.