  An algebraically expandable (AE) class is a class of algebraic structures
axiomatizable by sentences of the form $\forall \exists! \land p = q$. For a
logic $L$ algebraized by a quasivariety $\mathcal{Q}$ we show that the
AE-subclasses of $\mathcal{Q}$ correspond to certain natural expansions of $L$,
which we call {\em algebraic expansions}. These turn out to be a special case
of the expansions by implicit connectives studied by X. Caicedo. We proceed to
characterize all the AE-subclasses of Abelian $\ell$-groups and perfect
MV-algebras, thus fully describing the algebraic expansions of their associated
logics.
