Acoustic playback system

A speaker box comprising:

• a housing having an opening;
• a digital speaker being input k number of digital signals and disposed in the opening;
• a digital modulation circuit driving the digital speaker formed in the housing, wherein the digital modulation circuit includes a filter converting an input digital audio signal and outputting a digital signal of m bits;
• and
• k number of driving circuits, one part of the digital signal of m bits being input to the k number of driving circuits respectively, and the k number of driving circuits outputting the k number of digital signals to the digital speaker,
• wherein the digital modulation circuit further includes a ΔΣ modulation circuit and is disposed in close proximity to the digital speaker,
• wherein the digital modulation circuit filters a digital signal of a certain frequency bandwidth from the digital audio signal being input and performs noise shaping and miss match shaping, and
• wherein the digital modulation circuit further includes a controller controlling parameters of one or more digital signal processors operable upon a frequency bandwidth filtered by the digital modulation circuit, a noise shaping oversampling rate, and a degree of miss match shaping.