  We analyze the emission spectrum of a (fundamentally quantum) black hole in
the Kerr-Newman family by assuming a discretization of black hole geometry and
the holographic entropy-area relation. We demonstrate that, given the above
structure of black hole entropy, a macroscopic black hole always has
non-continuously separated mass states and therefore they descend down in
discrete manner. We evaluate the step size of the discrete spectrum, which
vanishes in the extremal limit, leading to a continuum spectrum as expected
from thermal nature of black holes. This further reveals an interesting
relation, in each class, between the dynamic and kinematic length scales for
all black holes belonging to the Kerr-Newman family, pointing towards a
possible universal character across the class, dependent only on black hole
mass. Further, we have presented the computation of maximum number of emitted
quanta from the black hole as well as an estimation of its lifetime. We also
argue the independence of these features from the presence of additional
spacetime dimensions.
