JVC RX-D Series Training Book page 79

MASTER CLOCK
MASTER CLOCK'S AMPLITUDE AND
DUTY CYCLE (BEFORE LPF)
The higher amplitude of the same duty cycle PWM, the output audio's
amplitude is higher, if the pulse width ratio are same.
OUTPUT AUDIO
VS
OUTPUT AUDIO AMPLITUDE
AFTER LPF
P-P 48V
P-P 80.6V