I do a lot of soldering with my other hobby (quadcopters / RC stuff), so I'm constantly soldering small circuit boards and wiring. I've found 700F to be the best all around temp especially when working with small parts. It allows you to get things done quickly as long as you understand you can't hold it there too long without doing damage, but at the same time you won't have to either. Flux is a must for everything, but use some isopropyl alcohol to clean the area afterwards.
It's also an incredible difference to have a good quality iron. They heat quickly, but most importantly re-heat very fast and stay consistent. You can find clones of Hakko 936 or 937's on Ebay or Amazon for $50-75. Even if you're just occasionally soldering it's still absolutely worth it and will last a lifetime. Those cheap $10-20 all in one wand irons are junk, but at the time you don't realize how much harder of a job you're making it. Once you switch to something decent it becomes enjoyable.
I'm still weary of working on expensive music gear though! I could probably do it, but would rather leave it to a pro when it comes to a something like an Elektron box or other high end item.