  The sound velocity $v_s$ and dimensionless tidal deformability $\Lambda$ are
analyzed using the pseudo-conformal model we developed before. In contrast to
the conclusion obtained in the previous works in the literature, our model with
the upper bound of the sound velocity $v_s = 1/\sqrt{3}$, the so-called
conformal sound velocity, set in at a { density relevant to compact stars}
$\gsim 2 n_0$ where $n_0$ is the normal nuclear matter density, can accommodate
{\it all} presently established nuclear matter and compact-star properties
including the maximum star-mass constraint $ \simeq 2.3 M_\odot$. This
observation is associated with a possible emergence of pseudoconformal
structure in compact star matter---in which the trace of energy-momentum tensor
is a nearly density-independent nonzero constant---brought in by a topology
change at $2.0 \lesssim n_{1/2}/n_0 \lesssim 4.0$ commensurate with a possible
change of degrees of freedom from hadrons.
