We have investigated Meyer-Neldel rule in thermally activated a.c. conduction for a-Se80Te20 and a-Se80Te10M10 (M = Cd, In, Sb) alloys by two different approaches. In the first case, the temperature dependence of a.c. conductivity is studied at different audio frequencies without changing the composition of glassy system. In the second case, the composition itself varies at a particular audio frequency. The results are explained by using well-known correlated barrier hopping model.