I see in the library that AR changed the crossover frequencies on the 2AX from older 2000 and 7500 to 1400 and 5000 on the newer model - >125,000 SN. I have an old pair a newer non-working pair and I notice that the capacitor values are identical - 4 and 6. How did AR change the crossover frequency while using the same caps and same 15 ohm pots?