Hi George, no I don't believe it's the .5 revison, although the 23.5 may have incorporated this change since it's a newer model than the 23.
I think the big difference in 23 vs. 23.5 is the 23.5 has Teflon circuit boards and (I've heard) all mil-spec parts. Other than the circuit board (and maybe the mil-spec parts), my understanding is that the two amps have the same circuit design.
I think the big difference in 23 vs. 23.5 is the 23.5 has Teflon circuit boards and (I've heard) all mil-spec parts. Other than the circuit board (and maybe the mil-spec parts), my understanding is that the two amps have the same circuit design.