If your system is, as you say, nothing fancy, then if I were you I would sell or give it away and just buy a similar thing here in the UK -- we do have them, and they are just like the ones you can get in the US. They can be had for the same pound-earned value too. I would bite the bullet and just buy one here if it's a bookshelf stereo system, a hair dryer, other highly replaceable items that both countries have plenty of.
I think that going to the trouble of bringing something easily and affordably replaceable, then having to deal with voltage conversions and transformers, is more energy and money spent than necessary.
Unless a piece of US electrical equipment is something expensive to replace, hard to find an equivalent of in the UK, or for some reason important to you, leave it behind and buy the same item over here.