Sound output device, sound output method, and storage medium

A sound output method implemented by a processor of a sound output device, the sound output device comprising an outer balancing circuit and an inner balancing circuit, the processor controlling the outer balancing circuit and the inner balancing circuit, and the method comprising:

• generating a first output signal for sound to be output from a first output device by mixing a left-channel signal and a right-channel signal based on a first ratio;
• generating a second output signal for sound to be output from a second output device by mixing the left-channel signal and the right-channel signal based on a second ratio;
• generating a third output signal for sound to be output from a third output device by mixing the left-channel signal and the right-channel signal based on a third ratio;
• and
• generating a fourth output signal for sound to be output from a fourth output device by mixing the left-channel signal and the right-channel signal based on a fourth ratio,
• wherein:
• the first and fourth output devices are outer speakers and the second and third output devices are inner speakers in a linear speaker array,
• the first and fourth output devices are balanced by the outer balancing circuit, and the second and third output device are balanced by the inner balancing circuit,
• the method comprises independently and variably setting the first through fourth ratios in accordance with user-settable Mid (m) and Side (s) component parameter values that are input according to a user designation of a first m/s ratio for a pair of the first and fourth sound output devices constituting the outer speakers of the linear speaker array and a user designation of a second m/s ratio for a pair of the second and third sound output devices constituting the inner speakers of the linear speaker array, and that control relative contribution of Mid and Side signal components to the first through fourth output signals, where the Mid and Side signal components are derived from the left-channel signal and the right-channel signal,
• the first to fourth ratios are set in accordance with the designated m/s ratio for each pair such that left/right sound localization of the original left-channel signal and right-channel signal is maintained within the corresponding pair and such that Mid/Side balance for one pair is independently adjustable from Mid/Side balance of the other pair,
• the Mid signal component comprises the sum of the left-channel and right-channel signals, and the Side signal component comprises the difference of the left-channel and right-channel signals, and
• the first output signal L1, the second output signal L2, the third output signal R3, and the fourth output signal R4 output from the outer balancing circuit and the inner balancing circuit are expressed by the following formulas:
• L1=L+(m out−s out)/2*R
• L2=L+(m in−s in)/2*R
• R3=R+(m in−s in)/2*L
• R4=R+(m out−s out)/2*L
• where:
• m out is a component adjustment parameter of the Mid component for the pair of the first and fourth output devices, and s out is a component adjustment parameter of the Side component for the pair of the first and fourth output devices, and
• m in is a component adjustment parameter of the Mid component for the pair of the second and third output devices, and s in is a component adjustment parameter of the Side component for the pair of the second and third output devices.

A non-transitory computer readable medium storing a program thereon, the program being executable by a processor of a sound output device, the sound output device comprising an outer balancing circuit and an inner balancing circuit, the processor controlling the outer balancing circuit and the inner balancing circuit, and the program being executable by the processor to control the processor to:

• generate a first output signal for sound to be output from a first output device by mixing a left-channel signal and a right-channel signal based on a first ratio;
• generate a second output signal for sound to be output from a second output device by mixing the left-channel signal and the right-channel signal based on a second ratio;
• generate a third output signal for sound to be output from a third output device by mixing the left-channel signal and the right-channel signal based on a third ratio;
• and
• generate a fourth output signal for sound from a fourth output device by mixing the left-channel signal and the right-channel signal based on a fourth ratio,
• wherein:
• the first and fourth output devices are outer speakers and the second and third output devices are inner speakers in a linear speaker array,
• the first and fourth output devices are balanced by the outer balancing circuit, and the second and third output device are balanced by the inner balancing circuit,
• the program causes the processor to independently and variably set the first through fourth ratios in accordance with user-settable Mid (m) and Side (s) component parameter values that are input according to a user designation of a first m/s ratio for a pair of the first and fourth sound output devices constituting the outer speakers of the linear speaker array and a user designation of a second m/s ratio for a pair of the second and third sound output devices constituting the inner speakers of the linear speaker array, and that control relative contribution of Mid and Side signal components to the first through fourth output signals, where the Mid and Side signal components are derived from the left-channel signal and the right-channel signal,
• the first to fourth ratios are set in accordance with the designated m/s ratio for each pair such that left/right sound localization of the original left-channel signal and right-channel signal is maintained within the corresponding pair and such that Mid/Side balance for one pair is independently adjustable from Mid/Side balance of the other pair,
• the Mid signal component comprises the sum of the left-channel and right-channel signals, and the Side signal component comprises the difference of the left-channel and right-channel signals, and
• the first output signal L1, the second output signal L2, the third output signal R3, and the fourth output signal R4 output from the outer balancing circuit and the inner balancing circuit are expressed by the following formulas:
• L1=L+(m out−s out)/2*R
• L2=L+(m in−s in)/2*R
• R3=R+(m in−s in)/2*L
• R4=R+(m out−s out)/2*L
• where:
• m out is a component adjustment parameter of the Mid component for the pair of the first and fourth output devices, and s out is a component adjustment parameter of the Side component for the pair of the first and fourth output devices, and
• m in is a component adjustment parameter of the Mid component for the pair of the second and third output devices, and s in is a component adjustment parameter of the Side component for the pair of the second and third output devices.