Best keys ever....I believe this is the best keyboard they ever made....powered by USB (it's easy to find AC to USB adapters)....that's all you need for a power cable.....they include a USB cable so you would only need the adapter.....it comes with free downloads for computer based sounds and....IT HAS A MIDI JACK (unlike so many new boards that only have USB).....I use it to control other keyboards & modules so I don't use the sounds you can download....I've played everything and everywhere since 1982 and these keys are my favorite......I would immediately buy another if it was ever stolen.....$400 for keys like these is a steal.....I never liked M Audio before this.....this board is built like a tank !! I'm really glad I gambled on it and it paid off...... Anyone who doesn't buy this is missing out big time !!!!