It is always true. There is no such thing as a power supply that will not suffer from this. Some are just better at dealing with it than others.
So you think that monoblock amps with a 750 VA transformer and 80,000 uf of capacitance in each amp will perform better than a stereo amp with a 5,000 VA transformer and 260,000 uf of capacitance.
So you think that monoblock amps with a 750 VA transformer and 80,000 uf of capacitance in each amp will perform better than a stereo amp with a 5,000 VA transformer and 260,000 uf of capacitance.