Does anyone here have much experience using their hardware (synths etc) in multiple countries? I currently live in the USA but will soon be moving to Germany. I’m worried that my gear (Octatrack, Nord lead a1, Microbrute, monitors etc) will get fried! Do I need to look into getting new power supplies?
Maybe… 
Depends on the gear. US is 110v; Europe is 220v; and different plugs of course.
Some gear will be rated for 100v-240v; which means you can use it anywhere around the world. Just replace the plug/cord.
e.g. my E-Mu Sampler is 100v-240v, and uses an IEC cord. Change the cord, and away you go.
If your gear is only rated for 110v or 240v; then you need a step up/down converter. If you do not use one of these you will fry your gear!
e.g. my Roland JD-990 came from the USA, and was only rated for is 110v; and had a fixed cord. To use it in a 240v country; I required a step-down convertor.
Note: A step down/up converter is NOT one of those cheap “travel plugs”. Don’t make that mistake.
Caveat: All care, no responsibility.
Your Octatrack will be fine, as they can be used around the world, due to the external power supply. Need a different Mains <> PowerPack plug. They are cheap/easy to get/find.
Nord Lead A1? Random photo off the internet… see how the sticker next to the power says 230v? So it’s a RoW model. If you plugged that into a US mains… 
Your one probably says 110v… i.e. a US version. If you Plug that into a 240v mains and… well, it was nice having a Nord wasn’t it?
So you would need a converter for the A1.
Thanks. So basically, if it has a universal power supply I just need the right plug. If it has a region specific power supply I need a converter?