Mackie CR4.5 Creative Reference Powered Studio Monitors combine professional-quality sound with a tone shaping knob for moving from studio reference to casual listening to party mode. Featuring a selection of inputs and switchable desktop and bookshelf modes, these speakers give you clear, powerful sound in any space. Use the tone control knob to adjust the sound, beginning with the transparent quality you expect from professional studio monitors, then gradually adding more excitement with boom-ier bass and added sparkle. Whether you're using them for business, pleasure or both, Mackie CR4.5 may be the only speakers you ever need.