Let’s say you wanted to put a pre-amp in your attic. Or, for that matter, any piece of electronic equipment. That shouldn’t be a problem, but there are two things you need to consider.
Access to power. While pre-amps can usually be plugged in downstairs, not every piece of equipment is designed to make things that easy. Most things need power, and most attics don’t have it. Before you plan on putting a lot of equipment up there, make sure you can plug it in.
Temperature. If a preamp or other equipment is designed to work outside, low temperatures probably aren’t an issue. If the equipment is designed to work inside, though, they might be. In either case, high temperatures are the real issue. Many attics reach temperatures above 120 degrees Fahrenheit. Some equipment isn’t rated to go that high. Most preamps will work with temperatures up to 140 degrees, but check out the specs on the specific equipment you want to buy.