The peculiar cabinet construction of the "Ballerina 301" gives this loudspeaker a very special sound emission. 

The isodynamic tweeter is completely embodied in the wood to express its full dynamics. 

The inverted dome midrange, thanks to its peculiar free space positioning and its carefully controlled back volume emits a back “coloration” that pleasingly contributes to the richness of  the ambience (see scheme on left side). 

The magnesium-aluminium alloy woofer, and its graphite mass loaded polyurethane box have, as well, a back emission, this creates a non invasive ambience sound (see scheme on the left). The bass is loaded trough a semi-Venturi double chamber that allows a very limited blow and a perfect phase matching of the driver.