Electronic sound synthesis

Claim 1

A system for producing electrical signals representing sounds of predetermined pitch and variable loudness value, wherein signals for each sound of predetermined loudness value comprise component signals corresponding to partial tones of said sound, said component signals having frequencies above a fundamental frequency determing the pitch of the sound and forming a spectral amplitude/frequency pattern when the amplitudes are plotted as a function of their frequency, and including at least one formant region represented by a maximum in said amplitude/frequency pattern; said spectral amplitude/frequency pattern determining the timbre of the sound; signals representing sounds of different loudness values differing in the shape of the amplitude/frequency pattern of the component signals; said system comprising a signal source including means (12, 14; 30, 34, 36) providing at least first and second signal versions for each sound of predetermined pitch, said first and second signal versions having component signal forming different first and second spectral amplitude/frequency patterns corresponding to different first and second loudness values, respectively; sound volume control means (20) for selecting a desired sound loudness value in a range between said first and second loudness values; control means (16, 16a; 18, 18a; 40, 42, 44a, 46, 48) connected to and controlled by the sound volume control means and further connected to the means (12, 14; 30, 34, 36) providing said signal versions for selecting a portion of said first signal version and a portion of said second signal version, the selection of the respective portions being controlled by said sound volume control means, for selecting the said sound loudness value and to vary said first and second portions inverse to each other and in accordance with the variations of the setting of said sound volume control selecting means; and means for combining said selected signal portions into a combined signal, which is the electrical sound signal to be produced.

Claim 2

A system for producing electrical signals representing sounds of predetermined pitch and variable loudness value, wherein signals for each sound of predetermined loudness value comprise component signals corresponding to partial tones of said sound, said component signals having frequencies above a fundamental frequency determing the pitch of the sound and forming a spectral amplitude/frequency pattern when the amplitudes are plotted as a function of their frequency, and including at least one formant region represented by a maximum in said amplitude/frequency pattern; said spectral amplitude/frequency pattern determining the timbre of the sound; signals representing sounds of different loudness values differing in the shape of the amplitude/frequency pattern of the component signals; said system comprising a signal source including means (12, 14; 30, 34, 36) providing at least first and second signal versions for each sound of predetermined pitch, said first and second signal versions having component signal forming different first and second spectral amplitude/frequency patterns corresponding to different first and second loudness values, respectively; sound volume control means (20) for selecting a desired sound loudness value in a range between said first and second loudness values; control means (16, 16a; 18, 18a; 40, 42, 44a, 46, 48) connected to and controlled by the sound volume control means and further connected to the means (12, 14; 30, 34, 36) providing said signal versions for selecting a portion of said first signal version and a portion of said second signal version, the selection of the respective portions being controlled by said sound volume control means, for selecting the said sound loudness value and to vary said first and second portions inverse to each other and in accordance with the variations of the setting of said sound volume control selecting means; and means for combining said selected signal portions into a combined signal, which is the electrical sound signal to be produced.

Claim 7

A method of producing electrical signals representing sounds of predetermined pitch and variable selectable loudness value, and having respective timbre corresponding to the loudness value selected, wherein said electrical signals comprise component signals representing partial tones of said sound having frequencies above a fundamental frequency determining the timbre of said sound, said component signals forming a spectral amplitude/frequency pattern of predetermined shape when the amplitudes are plotted as a function of their frequency, said pattern including at least one formant region represented by a maximum in said pattern, said method comprising the steps of providing at least first and second signal versions for each sound of predetermined pitch, said first and second signal versions having component signals forming different first and second spectral amplitude/frequency patterns corresponding to different first and second loudness values, respectively; selecting a portion of said first signal version, and selecting a portion of said second signal version in accordance with a desired sound loudness value, said selection step including selecting said sound loudness values of said first and second portions inverse to each other to increase the level of a first portion when the level of the other portion decreases, or vice versa; and combining said selected signal portions into a combined signal to produce said electrical signals representing said sounds of predetermined pitch and timbre.

Claim 8

A method of producing electrical signals representing sounds of predetermined pitch and variable selectable loudness value, and having respective timbre corresponding to the loudness value selected, wherein said electrical signals comprise component signals representing partial tones of said sound having frequencies above a fundamental frequency determining the timbre of said sound, said component signals forming a spectral amplitude/frequency pattern of predetermined shape when the amplitudes are plotted as a function of their frequency, said pattern including at least one formant region represented by a maximum in said pattern, said method comprising the steps of providing at least first and second signal versions for each sound of predetermined pitch, said first and second signal versions having component signals forming different first and second spectral amplitude/frequency patterns corresponding to different first and second loudness values, respectively; selecting a portion of said first signal version, and selecting a portion of said second signal version in accordance with a desired sound loudness value, said selection step including selecting said sound loudness values of said first and second portions inverse to each other to increase the level of a first portion when the level of the other portion decreases, or vice versa; and combining said selected signal portions into a combined signal to produce said electrical signals representing said sounds of predetermined pitch and timbre.