While originally inspired by the 5C sound cubes from decades ago, the Avantone MixCubes have become the industry standard in studios around the world and have become the #1 best selling speaker of its type in history. Engineering Objective To build a full range, rugged, mini-reference monitor to replace the older, aging, 5C Sound Cubes that are still in use worldwide, while offering an improved, more linear frequency response. A full year was spent studying all versions & revisions of the famous little 5C Sound Cubes. Research revealed that there were several driver versions released over the years with widely varying frequency response characteristics. We chose the smoothest, most linear, full-range version of those 5C models to use as our testing benchmark. Next we analyzed their response characteristics in an anechoic chamber and proceeded to implement design upgrades. Realizing the importance of replacing a respected "industry-standard reference monitor" we began by replicating its basic size, function, and sonic character. We wanted to take it up a notch though... First, we addressed the Cabinet Design... The original 5C Sound Cubes were made of ½” particleboard covered with a glue-on wood grain contact paper. We chose to use thicker, denser MDF board because of its high rigidity and inherent low-resonance characteristics. We started with a 165mm (6 1/2") sealed cube design with radiused edges. We then chose an elegant Polyurethane high gloss “RETRO-CREAM” finish. The originals had either screws or on later models plastic binding posts mounted on a recessed plastic cup.