A quote from Vinnie Rossi audio site see below:
’’With active power factor correction (PFC) and superior regulation and stability, the power supply ensures maximum performance regardless of AC mains quality. Housed in a fully enclosed compartment precision machined into Brama’s solid aluminum body, it is fully grounded and isolated from the audio circuitry, performing like a highly-responsive, well-tuned engine.’’ See Vinnie Rossi here.
Mike