I've recently had the privilege of restoring a pair of each of these. The A 25 proved to be a particularly pleasant surprise in the form of a very early version with Scanspeak Drivers and the FG stuffed vent located ABOVE the tweeter (see pics). The A 25 had a conventional crossover with 6 resistors and one 8 uF Jensen NPE cap. I replaced the cap with a Sonicap 8 uF, cleaned the rotary switch and left the original resistors intact. The rotary switch forms a conventional 2 resistor L-pad combini