Hi @hasmarto,
Yes I agree that the way LTA describes the total capacitance sounds like they describe it as amplification design. If there is such capacitance in their DAC it is most likely to smoothen the edge of ZOTL design they use. BTW as I mentioned I have a capacitance MOSFET multiplier which works like that: You have a capacitor on gate of MOSFET and you multiply this capacitate by amplification(beta) of the transistor. Let's say the "beta" of transistor is 200. I have 680uf x 200= 136000uf right there. And this is a linear power supply. If I remember well LTA picture shows only one transformer and they say they use DC to DC power supply and such DC to DC converters are around $5 a piece. This is switching power supply. That explains the 300000uf. They need that capacitance.