Electronic musical instruments, method and storage media therefor

A method executed by at least one processor in an electronic musical instrument that includes, in addition to the at least one processor, a performance controller, the method comprising, via the at least one processor:

• instructing sound generation of a first musical tone in response to a first operation on the performance controller;
• in response to a second operation on the performance controller during the sound generation of the first musical tone, obtaining a first amplitude value of the first musical tone at a time of the second operation, and obtaining a second amplitude value at which a second musical tone is to be sound-produced in response to the second operation on the performance controller;
• acquiring a parameter value for determining at least one of pitch, timbre, and volume of the second musical tone based on a ratio of the first amplitude value to the second amplitude value;
• and
• instructing sound generation of the second musical tone in accordance with the acquired parameter value,
• wherein the parameter value is acquired by the following equation:
• parameter value=log2(a/b)+N,
• where a is the first amplitude value, b is the second amplitude value, and N is an adjustment parameter for setting the parameter value to a value of zero or more.

A computer readable non-transitory storage medium storing therein instructions, the instructions causing at least one processor in an electronic musical instrument that includes, in addition to the at least one processor, a performance controller to perform the following:

• instructing sound generation of a first musical tone in response to a first operation on the performance controller;
• in response to a second operation on the performance controller during the sound generation of the first musical tone, obtaining a first amplitude value of the first musical tone at a time of the second operation, and obtaining a second amplitude value at which a second musical tone is to be sound-produced in response to the second operation on the performance controller;
• acquiring a parameter value for determining at least one of pitch, timbre, and volume of the second musical tone based on a ratio of the first amplitude value to the second amplitude value;
• and
• instructing sound generation of the second musical tone in accordance with the acquired parameter value,
• wherein the parameter value is acquired by the following equation:
• parameter value=log2(a/b)+N,
• where a is the first amplitude value, b is the second amplitude value, and N is an adjustment parameter for setting the parameter value to a value of zero or more.