I need new speakers for my wife´s digital piano and also for our iMac. I no very little about audio and speakers and I´m wondering whether it is a good idea to connect the digital piano through the iMac or to buy separate speakers and amplifier. Is the quality the same or very different? I don´t know the difference between computer speakers and normal speakers that are connected with amplifiers and why computer speakers don´t need amplifiers. We live in a small appartment so we don´t need enough power so that 1000 people can listen, all we want is high quality music sound. The budget is several hundred $, depending on what is the best value.