Is it ok for the power supply being used to have more milliamps than the equipment is rated for?

i have a digitech quad effects unit and cant find the original power supply but i have a vox tonelab with a similar looking and same 4 pin setup that fits into the back of the digitech perfectly... both pieces of equipment use 9v conversion adapters... but the vox has a 3,000 milliamp output rating and the back of the digitech has a 2.2 amp (2,200milliamp) rating printed on the back... i have heard that when using replacement/alternate power adapters the positive/negative terminals need to match, the volts need to match (9v,12v,16v..etc) and the milliamp rating on the adapter needs to be equal to or higher than the milliamp rating the equipment... i think?.... does that make any sense to anyone and does anyone know for sure? thanx for your time... Steve