Apparatus and a method for controlling a sound field

An apparatus for controlling a sound field, comprising:

• a control filter configured to convolute a first filter coefficient and a second filter coefficient with a first acoustic signal to generate a second acoustic signal and a third acoustic signal;
• a first speaker to radiate a sound toward a first area having a first control point and a second area having a second control point, based on the second acoustic signal;
• a second speaker to radiate a sound toward the first area and the second area, based on the third acoustic signal;
• and
• a storage unit configured to store the first filter coefficient and the second filter coefficient calculated by using spatial transfer characteristics from the first speaker and the second speaker to the first control point and the second control point, and a first sound increase ratio na at the first control point and a second sound increase ratio nb at the second control point, so that a first composite sound pressure from the first speaker and the second speaker to the first control point is na times a first sound pressure from the first speaker to the first control point when the first filter coefficient is a through characteristic, and so that a second composite sound pressure from the first speaker and the second speaker to the second control point is nb times a second sound pressure from the first speaker to the second control point when the first filter coefficient is the through characteristic.

A method for controlling a sound field in a system including a first speaker and a second speaker, comprising:

• convoluting a first filter coefficient and a second filter coefficient with a first acoustic signal to generate a second acoustic signal and a third acoustic signal;
• radiating by the first speaker, a sound toward a first area having a first control point and a second area having a second control point, based on the second acoustic signal;
• radiating by the second speaker, a sound toward the first area and the second area, based on the third acoustic signal;
• and
• calculating the first filter coefficient and the second filter coefficient by using spatial transfer characteristics from the first speaker and the second speaker to the first control point and the second control point, and a first sound increase ratio na at the first control point and a second sound increase ratio nb at the second control point, so that a first composite sound pressure from the first speaker and the second speaker to the first control point is na times a first sound pressure from the first speaker to the first control point when the first filter coefficient is a through characteristic, and so that a second composite sound pressure from the first speaker and the second speaker to the second control point is nb times a second sound pressure from the first speaker to the second control point when the first filter coefficient is the through characteristic.