摘要:
A method of modeling (fig. 4, fig. 5) a characteristic of a non-linear system (21), comprises feeding test input signals (Sig6, Sig7) into the non-linear system (21) to obtain test output signals (Resp6, Resp7), wherein the test input signals (Sig6, Sig7) include a first test input signal (Sig6) and the test output signals (Resp6, Resp7) include a first test output signal (Resp6), identifying occurrences when an output level in at least one specific frequency band of the first testing output signal significantly changes under the first test input signal (e.g. identifying the frequencies at which there are overtones) so as to obtain a first profile (Profile B: frequency index versus input level, fig. 7), and modeling the characteristic (e.g. frequency response of pre-amplifier stage, fig. 8) based on the first profile (fig. 20). Various test input signals may be used : Amplitude sweep (fig. 6a-c), frequency sweep (fig. 10), white noise or chirp signal. The breakup point of overtones onsets in the table of frequency bins versus input signal is determined. The application of this profile to model the non-linear amplifier stage of a music instrument, for instance a guitar, is also defined.
摘要:
A method of modeling (fig. 4, fig. 5) a characteristic of a non-linear system (21), comprises feeding test input signals (Sig6, Sig7) into the non-linear system (21) to obtain test output signals (Resp6, Resp7), wherein the test input signals (Sig6, Sig7) include a first test input signal (Sig6) and the test output signals (Resp6, Resp7) include a first test output signal (Resp6), identifying occurrences when an output level in at least one specific frequency band of the first testing output signal significantly changes under the first test input signal (e.g. identifying the frequencies at which there are overtones) so as to obtain a first profile (Profile B: frequency index versus input level, fig. 7), and modeling the characteristic (e.g. frequency response of pre-amplifier stage, fig. 8) based on the first profile (fig. 20). Various test input signals may be used : Amplitude sweep (fig. 6a-c), frequency sweep (fig. 10), white noise or chirp signal. The breakup point of overtones onsets in the table of frequency bins versus input signal is determined. The application of this profile to model the non-linear amplifier stage of a music instrument, for instance a guitar, is also defined.
摘要:
A system (50) for modifying an audio signal (Audo1) comprises a portable device (50) including at least one digital signal processor DSP. The DSP comprises a first module (503) and a second module (504). The first module (503) is coupled to the interface (501) to provide a reference electric musical instrument (502) with a set of input test signals (Sig9) and obtain a set of test output signals (Resp9) via the interface (501). The second module (504) is configured to perform functions including: Analysing the set of test output signals (Resp9) to obtain a set of parameters (Prm1); parameterizing an acoustic transducer (505) and a modeler (30) to model characteristics of the reference electric musical instrument (502) based on the set of parameters (Prm1); Receiving the audio signal (Audo1) from a played musical instrument (63 / 502) to modify it into a second audio signal (Audo2) using the modeler (30) and the acoustic transducer (505), wherein the first module obtains the set of parameters (Prm1) at least by identifying frequency bins where overtones occur in the test output signals (Resp9). The set of parameters comprises two profiles (Profile A, Profile B), gain characteristics, breakup value, pre-/post-amplifiers characteristics, measured beforehand via the interface, stored and made available in the cloud. Another embodiment provides a system (60) comprising a first host (61) and a second host (62). The first host measures a reference electric musical instrument (502) via a first and second modules (503, 504) and sends the obtained set of parameters (Prm1) of a corresponding physical model over the cloud; the second host (62) retrieves the set of parameters (Prm1) from the cloud and modifies via a third module (620) the audio (Sig10) input from an actual music instrument (63) in real time, to produce an output signal (Resp10) having a similar timbre as the reference electric music instrument (502).
摘要:
A system (50) for modifying an audio signal (Audo1) comprises a portable device (50) including at least one digital signal processor DSP. The DSP comprises a first module (503) and a second module (504). The first module (503) is coupled to the interface (501) to provide a reference electric musical instrument (502) with a set of input test signals (Sig9) and obtain a set of test output signals (Resp9) via the interface (501). The second module (504) is configured to perform functions including: Analysing the set of test output signals (Resp9) to obtain a set of parameters (Prm1); parameterizing an acoustic transducer (505) and a modeler (30) to model characteristics of the reference electric musical instrument (502) based on the set of parameters (Prm1); Receiving the audio signal (Audo1) from a played musical instrument (63 / 502) to modify it into a second audio signal (Audo2) using the modeler (30) and the acoustic transducer (505), wherein the first module obtains the set of parameters (Prm1) at least by identifying frequency bins where overtones occur in the test output signals (Resp9). The set of parameters comprises two profiles (Profile A, Profile B), gain characteristics, breakup value, pre-/post-amplifiers characteristics, measured beforehand via the interface, stored and made available in the cloud. Another embodiment provides a system (60) comprising a first host (61) and a second host (62). The first host measures a reference electric musical instrument (502) via a first and second modules (503, 504) and sends the obtained set of parameters (Prm1) of a corresponding physical model over the cloud; the second host (62) retrieves the set of parameters (Prm1) from the cloud and modifies via a third module (620) the audio (Sig10) input from an actual music instrument (63) in real time, to produce an output signal (Resp10) having a similar timbre as the reference electric music instrument (502).