  Let $G$ be a locally compact group and $(\Phi, \Psi)$ be a complementary pair
of $N$-functions. In this paper, using the powerful tool of porosity, it is
proved that when $G$ is an amenable group, then the
Fig\`a-Talamanca-Herz-Orlicz algebra ${\A}_{\Phi}(G)$ is a Banach algebra under
convolution product if and only if $G$ is compact. Then it is shown that
${\A}_{\Phi}(G)$ is a Segal algebra, and as a consequence, the amenability of
${\A}_{\Phi}(G)$ and the existence of a bounded approximate identity for
${\A}_{\Phi}(G)$ under the convolution product is discussed. Furthermore, it is
shown that for a compact abelian group $G$, the character space of
${\A}_{\Phi}(G)$ under convolution product can be identified with
$\widehat{G}$, the dual of $G$.
