what do you mean convert? are you referring to different countries voltages? Japan @ 100v, NA @ 115v and Europe etc. @ 220v.
you should note Japan’s voltage and NA’s voltage are close but not close enough to run a 100v Japan model on NA’s 115v. you would need a voltage step down for the Japan model and step up transformer for the 220v assuming your in NA 115v.
I’m not sure about your specific amp and if it has a switch on the back to change supply voltages, your manual would have that as for internal changes again your manual should have that if available. chances are the manufacturer only puts the transformer in the chassis for the voltage in the country being sold, if its not switchable on the back.
If your trying to run an amp made for another countries voltage you will need a step up or step down transformer. quality ones are available online. Make sure you get one that exceeds the rated max power draw of the amp plugged into it. this can be found on the back in watts. potted transformers in the step up/down transformer would be the best but rarer.
For example a standard 15amp 115v outlet in a NA house has a max draw of approx. 1500watts. your amps max wattage 570w draw then buy a step up or step down transformer that is at least 25% larger then the max. you should buy a 750w-1000w transformer probably the 1000w as that’s a standard size and will give enough head room to never be a concern.
from the E5000 manual below:
Power requirements 120 V, 220 V, 230 V AC (voltage as indicated on rear panel) 50 / 60 Hz
Power Consumption Idle 98 W In accordance with IEC 60065 570 W, Stand-by 0.3 W
