If they are from the same series / era of production, you won't have any problems. They are near identical designs with one just having higher rail voltages and more current with the associated increase in output devices necessary to pass the higher amount of power. Just bare in mind that B&K has had gobs of production changes in the last twenty years and the amps could have completely different output devices in them with the associated changes in support circuitry. If in doubt, contact Jerry at B&K in their tech support department. Great guy and very down to Earth. If need be, you can even send your amps in and B&K will set them up for identical operation ( short of power output ). Sean
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