JP4240480B2 - Reverberation effect adding device - Google Patents

Description

  The present invention relates to a reverberation effect adding device that adds an effect by simulating the reverberation effect of an acoustic piano.

  The damper pedal in an acoustic piano is to release a damper (silencer) that stops the vibration of the piano strings for all strings. When the damper pedal is depressed, the keys are pressed. Even if the key is released, the reverberant sound continues to sound. Also, proposals have been made to simulate this reverberation effect in electronic musical instruments. For example, in order to simulate the reverberation effect, a comb filter having a plurality of resonance frequency peaks is associated with 12 pitch names in one octave, and a PCM musical sound signal is input to the comb filter to simulate the reverberation effect. Has been proposed (see, for example, Patent Document 1).

JP-A 63-267999 (page 4-5, FIG. 4)

  Certainly, according to this prior art, in addition to the musical tone signal corresponding to the designated pitch name, a sounding signal having a frequency different from that of the designated pitch name is generated. Although it is possible to simulate the reverberation effect caused by the influence of other string vibrations, it is not possible to simulate the two-dimensional spread of the reverberant sound in the depth direction and the left-right direction, and the actual reverberation effect is realistically simulated. It was difficult to do.

  The present invention has been made to solve such a conventional problem, and an object of the present invention is to provide a reverberation effect adding device that imitates the reverberation effect of an acoustic piano more realistically and adds the effect.

In order to achieve the above object, the present invention provides one or more low-pass filters, one or more all-pass filters in a delay loop in which a first delay device and a second delay device are connected in a loop. , one or more attenuated coefficient multiplier and, which is a pitch name number of octave depth reverberation circuit connected so as to constitute the delay loop 12 Kosonae,
In each depth reverberation circuit, the sum of the delay time of the first delay device and the delay time of the second delay device is set to a value corresponding to the period of the sound of each pitch name,
The near side input signal recorded at a predetermined position on the near side of the acoustic piano is commonly input to the first delay unit in each depth reverberation circuit, and the second delay unit in each depth reverberation circuit receives the acoustic piano's input signal. The back side input signal recorded at a predetermined position on the back side is configured to be input in common, and each of the near side input signal and the back side input signal in each depth reverberation circuit is a delay loop of each depth reverberation circuit. Are output as a near-side output signal and a back-side output signal, respectively, and are configured so that the near-side output signals and the back-side outputs of each depth reverberation circuit are added together,
A first adder for adding the near side input signal and the near side output signal; and a second adder for adding the back side input signal and the back side output signal. I tried to do it.

More specifically, the first low-pass filter, the first delay unit, the first attenuation coefficient multiplier, the second low-pass filter, the all-pass filter, the second delay unit, the second delay unit, It has 12 depth reverberation circuits that connect attenuation coefficient multipliers in a loop, which is the number of pitches in one octave,
In each depth reverberation circuit, the sum of the delay time of the first delay device and the delay time of the second delay device is set to a value corresponding to the period of the sound of each pitch name,
The near side input signal recorded at a predetermined position on the near side of the acoustic piano is commonly input to the first delay unit in each depth reverberation circuit, and the second delay unit in each depth reverberation circuit receives the acoustic piano's input signal. The back side input signal recorded at a predetermined position on the back side is configured to be input in common,
The front side input signal and the back side input signal in each depth reverberation circuit circulate around the loop of each depth reverberation circuit, respectively, and are output as the front side output signal and the back side output signal, respectively, before the depth reverberation circuit. The side output signals and the back side output signals are added together,
A first adder for adding the near side input signal and the near side output signal; and a second adder for adding the back side input signal and the back side output signal. A reverberation effect adding circuit is provided. The reverberation effect addition circuit may further include a circuit that changes the coefficients of the first and second attenuation coefficient multipliers in each depth reverberation circuit according to the depression amount of the damper pedal.

According to another aspect of the present invention, a delay unit, an attenuation coefficient multiplier, a low-pass filter, an output unit provided after the low-pass filter, and a sound input unit for a certain channel provided after the low-pass filter DOO delay segments (m-number of channels from the first channel to the m Ji catcher tunnel: m is an integer of 2 or more) a plurality of channels having as connected in series by the number of channels of the tone signal, and all-pass filter With 12 reverberation circuits connected in a loop, which is the number of pitches in one octave,
In each cyclic reverberation circuit, set the total value of the delay times by the delay segments of the delay segment for the number of channels (m) to correspond to the period of the sound of each pitch name,
Musical sound signals from the first channel to the m-th channel, which are reproduction signals of signals recorded at m points of the acoustic piano , are input to the first to m-th delay segment input sections in each circulation reverberation circuit. , Each of the 12 reverberation circuits is commonly input, and the output from the first delay segment to the m-th delay segment in each of the reverberation circuits has a corresponding channel. A musical sound signal is output by circulating the reverberation circuit , and the output signals of the same channel in each of the twelve reverberation circuits are added together for each channel and output. Output that outputs the m tone signals by adding the channel tone signals to the corresponding channel input signals. There is provided a reverberation effect addition circuit including a circuit. In this reverberation effect addition circuit, the plurality of channels of tone signals can be reproduced signals of signals recorded at a plurality of locations on the acoustic piano. Furthermore, it is also possible to employ a configuration in which a low cut filter is connected in the loop shape and a circuit for bypassing the low cut filter when the damper pedal is depressed.

  Furthermore, in the above reverberation effect adding circuit, a pedal depression speed detecting means for outputting a depression speed coefficient corresponding to the depression speed of the damper pedal, and the output depression speed coefficient and the recording performed in advance when the damper pedal is depressed. Multiplying means for multiplying the damper release noise, and output means for outputting the multiplication result may be further provided.

  According to the present invention, it is possible to obtain an effect that the reverberation effect of an acoustic piano can be simulated more realistically and added.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(Reverberation effect adding device with depth reverberation circuit)
FIG. 1 is a configuration diagram of the depth reverberation circuit 100, and FIG. 2 is a configuration diagram of the electronic musical instrument 1 including the reverberation effect addition circuit 1000 configured by including the 12 depth reverberation circuits 100. FIG. 3 is an explanatory diagram when acquiring waveform data to be recorded and stored in the waveform memory 125. FIG. 3 is a schematic view of the acoustic grand piano 1100 as seen in a plan view. The left position (FL), the center position (FC), the right position (FR) on the front side (side with the keyboard), the back side (FR) Recording is performed with a microphone by pressing each of 88 keyboards (not shown) included in the keyboard unit 110 at five microphone points at the left position (RL) and the right position (RR) on the opposite side of the keyboard. The obtained waveform data is stored in the waveform memory 125. That is, 5 channels of waveform data are stored in the waveform memory 125 so as to be reproducible for each of the 88 keys. The total number of keyboards is not limited to 88, and the number of microphone points is not limited to five.

(Depth reverberation circuit 100)
First, the configuration and operation of the depth reverberation circuit 100 will be described with reference to FIG. The depth reverberation circuit 100 includes an LPF (low-pass filter) 10 (first low-pass filter), a delay R30 (first delay unit), and a multiplier 50 (first attenuation coefficient multiplier) having a coefficient α. LPF (low-pass filter) 20 (second low-pass filter), all-pass filter 60, delay L35 (second delay device), and multiplier 55 (second attenuation coefficient multiplier) having a coefficient β. Connected in a loop. The LPF 10 has a configuration in which a multiplier 14 is connected to a delay element 18, and an output of the multiplier 14 and an output of the multiplier 12 are added by an adder 16. The LPF 20 is configured such that a multiplier 24 is connected to the delay element 28, and an output of the multiplier 24 and an output of the multiplier 22 are added by an adder 26. The all-pass filter 60 adds the output of the delay element 68 and the output of the multiplier 62 having the coefficient “k” by the adder 64, and outputs the output of the LPF 20 and the output of the multiplier 63 having the coefficient “−k”. Are added by an adder 66, and this filter has a function of shifting the phase of the signal.

  An LPF 70 is also provided outside the loop. The LPF 70 has a configuration in which a multiplier 73 is connected to a delay element 74 and the output of the multiplier 73 and the output of the multiplier 72 are added by an adder 76. The pedal depression information of a damper pedal (not shown) is input to the LPF 70. The coefficient α of the multiplier 50 and the coefficient β of the multiplier 55 are changed and controlled by the output of the LPF 70. When the pedal depression information indicates that the damper pedal is not depressed, the values of the coefficients α and β of the multiplier 50 and the multiplier 55 are close to “0” in order to quickly attenuate the signal in the loop. On the other hand, when the pedal depression information indicates that the damper pedal has been depressed, the coefficients α and β of the multiplier 50 and the multiplier 55 are set so as to make it difficult to attenuate the signal in the loop. The value is set to a value close to “1”, for example, about “0.99”, and the signal attenuation characteristic in the loop is controlled. The LPF 70 is for smoothing this switching.

  An adder 40 is connected in the loop between the LPF 10 and the delay R30, and an adder 45 is connected in the loop between the all-pass filter 60 and the delay L35. A side input signal is added and a back side input signal is added to the adder 45. The combination of the near side input signal and the far side input signal is “a recording signal at the FL position and the RL position” or “a recording signal at the FR position and the RR position” shown in FIG. Here, it is assumed that the near side input signal is recorded at the FL position, and the far side input signal is recorded at the RL position.

  The near-side input signal input into the loop is delayed by the sum of the delay time of the delay R30 and the delay time of the delay L35 by one round of the loop, and is output as the near-side output signal. Therefore, if the sum of the delay time of the delay R30 and the delay time of the delay L35 is a period of a specific pitch name of one octave, for example, the pitch name “C”, the peaks and peaks of the input signal on the near side are overlapped. The circuit resonates with the sound of the pitch name “C”. The same applies to the case where the back side input signal is input into the loop. The front side input signal input into the loop makes one round of the loop, so that the delay time of the delay R30 and the delay L35 Delayed by the sum of the delay time and output as a back side output signal. Therefore, if the sum of the delay time of the delay R30 and the delay time of the delay L35 is the period of the pitch name “C”, the peaks of the back side input signal are overlapped and the pitch of the pitch name “C” is overlapped. Resonate. Thus, the depth reverberation circuit 100 adjusts the sum of the delay time of the delay R30 and the delay time of the delay L35 so as to resonate with a specific sound.

  The electronic musical instrument 1 of FIG. 2 has a reverberation effect adding circuit 1000 including 12 depth reverberation circuits 100-1 to 100-12 corresponding to the number of pitch names of one octave. The depth reverberation circuits 100-1 to 100-12 each adjust the sum of the delay time of the delay R30 and the delay time of the delay L35, and each of the pitch names “C, C #,..., B” of one octave is adjusted. It is configured to resonate with sound. In addition, with respect to each of the delay R30 and the delay L35 in each of the depth reverberation circuits 100-1 to 100-12, the acoustic piano is located at the FL position (predetermined position on the front side) and the RL position (predetermined position on the rear side). The front side input signal and the back side input signal recorded in this manner are input in common, and the front side output signals and the back side output signals in each of the depth reverberation circuits 100-1 to 100-12 are respectively connected. Further, the adder 130 (first adder) that adds the near side input signal and the near side output signal and the adder 131 that adds the far side input signal and the far side output signal are added. (Second adder). The outputs of the adders 130 and 131 are digital / analog converted by the D / A converter 140 and emitted from the speaker 150. In addition, pedal depression information from the pedal depression amount detection unit 115 that detects and outputs the pedal depression amount is input to the LPF 70 in each of the depth reverberation circuits 100-1 to 100-12. When the pedal depression amount is “0”, the damper pedal is not depressed, and when the pedal depression amount is larger than “0”, the damper pedal is depressed and the pedal is fully depressed. Is detected as “1”. Therefore, the pedal depression amount detector 115 outputs a value from “0” to “1” according to the depression amount of the pedal.

  The keyboard unit 110 is configured to output information about 88 keys (not shown) and keys pressed to the sound source unit 120. The sound source unit 120 includes a waveform memory 125 that stores the waveform described above, and based on the information of the key that has been pressed, the corresponding front side input signal (recorded signal at the position of the FL) and back side input signal ( The recording signal at the RL position) is read from the waveform memory 125 and output.

(Operation)
For example, when the lowest C key is pressed, information indicating that the lowest “C” key is pressed is output from the keyboard unit 110 to the sound source unit 120. In response to this, the sound source unit 120 reads out the corresponding near side input signal (recording signal at the position of FL) and the back side input signal (recording signal at the position of RL) from the waveform memory 125 and outputs them. Each of the depth side reverberation circuits 100-1 to 100-12 receives the front side input signal and the back side input signal in common, but the depth reverberation circuit 100 adjusted so as to resonate with the pitch name “C”. The output from -1 is the largest. Then, the near side output signals and the far side output signals in each of the depth reverberation circuits 100-1 to 100-12 are added together, and the adder 130 adds the near side input signal and the near side output signal, and adds them. The device 131 adds the back side input signal and the back side output signal, and this added signal is digital-analog converted by the D / A converter 140 and emitted from the speaker 150. In this way, the reverberation of the sound corresponding to the pressed key can be reproduced with a spread in the depth direction. When a plurality of keys are pressed simultaneously instead of one key, the same effect can be obtained by the operation of the corresponding depth reverberation circuits 100.

  2 shows the recording signals at the FL position and the RL position as the front side input signal and the back side input signal, respectively. 12 depth reverberation circuits 100, which are the front side input signal and the back side input signal, respectively, of the recording signals at the position and the RR position are further provided. A more realistic reverberation effect is added by adding a reverberation effect in the depth direction.

  In addition, the depth reverberation circuit 100 of FIG. 1 includes two LPFs (10, 20), two delay units (30, 35), two attenuation coefficient multipliers (50, 55), and one piece. In theory, one or more low-pass filters and one or more all-pass filters are connected in a delay loop in which two delay devices are connected in a loop. It is sufficient to connect the filter and one or more reduction coefficient multipliers so as to form the delay loop.

(Reverberation effect adding device with circulation reverberation circuit)
4 is a configuration diagram of the reverberation circuit 200, FIG. 5 is an internal view of a delay segment that constitutes the reverberation circuit 200, and FIG. 6 includes a reverberation effect addition circuit 1001 that includes 12 reverberation circuits 200. FIG. Since the pedal depression amount detection unit 115, the keyboard unit 110, and the sound source unit 121 in FIG. 6 are the same as those shown in FIG. The D / A 141 performs 5 channel digital / analog conversion, and the speaker 151 emits the 5 channel sound. Note that the five channels correspond to waveform data recorded at five locations “FL, FC, FR, RL, RR” in FIG.

(Circulating reverberation circuit 200)
First, the configuration and operation of the reverberation circuit 200 will be described with reference to FIG. The reverberation circuit 200 has a plurality of delay segments (90, 92, 94, 96, 98) of music (generally, m channels from the first channel to the m-th channel: m is an integer of 2 or more). The number of signal channels, in this example, only five are connected in series and the all-pass filter 80 are connected in a loop. Delay segment 1 (90), delay segment 2 (92), delay segment 3 (94), delay segment 4 (96), and delay segment 5 (98) correspond to channel 1 to channel 5 (ch1 to ch5), respectively. Is. In the all-pass filter 80, the output of the delay element 88 and the output of the multiplier 82 having the coefficient “k” are added by the adder 86, and the output of the delay segment 90 and the multiplier 83 having the coefficient “−k” are added. The output is added by the adder 84, and this filter has an effect of shifting the phase of the signal.

  Further, as shown in FIG. 5, each delay segment (in particular, the delay segment 4 (96) is shown in FIG. 5) includes a delay unit 165, a multiplier 166 having a coefficient α, an LPF 160, and the LPF 160. A multiplier 167 provided in the subsequent stage, and an adder 169 that adds the output of the multiplier 168 (input unit) that inputs a sound of a certain channel and the output of the multiplier 167 are provided. A connection point between the LPF 160 and the multiplier 167 has an output unit that can output the sound of the channel. The LPF 160 has a configuration in which a multiplier 161 is connected to the delay element 163 and the output of the multiplier 161 and the output of the multiplier 162 are added by an adder 164. Note that the multiplier 167 enables the signal to be phase-inverted, and is normally set so that the coefficient is “1” and the coefficient is “−1” at the time of phase inversion. When the pedal depression information indicates that the damper pedal is not depressed, the multiplier 166 coefficient α value is set to a value close to “0”, for example, “0.01” in order to quickly attenuate the signal in the loop. On the other hand, when the pedal depression information indicates that the damper pedal is depressed, the coefficient value of the multiplier 166 is set to a value close to “1”, for example, “0.99” in order to make it difficult to attenuate the signal in the loop. The signal attenuation control is performed within the loop.

  As an example, each of channel 1 to channel 5 (ch1, ch2, ch3, ch4, ch5) is made to correspond to “RL”, “RR”, “FR”, “FC”, “FL” in FIG. . That is, the rear left position signal recorded at the “RL” position is input / output to the delay segment 1 (90), and the rear right signal recorded at the “RR” position is input to the delay segment 2 (92). The position signal is input / output, the front right position signal recorded at the position “FR” is input / output to the delay segment 3 (94), and the signal “FC” is input to the delay segment 4 (96). The recorded front center position signal is input / output, and the front segment left position signal recorded at the “FL” position is input / output to the delay segment 5 (98).

  Now, paying attention to the delay segment 1 (90), when a signal (channel ch1 signal) at the far side is input from “in” and the circuit loops around the delay loop, each delay segment 90, 92, 94, 96, The output signal of the rear left position is output from “out” after being delayed by five delay devices 165 of 98. Similarly, when a signal (channel ch2 signal) at the far side is input from “in” to the delay segment 2 (92) and the circuit loops around the delay loop, each delay segment 90, 92, 94, 96, The output signal of the rear right position is output from its “out” after being delayed by the five delay devices 165 of 98, and the signal of the front right position from the “in” (channel ch3 signal) is output to the delay segment 3 (94). ) Is input to make one round of the delay loop, it is delayed by the five delay units 165 of each delay segment 90, 92, 94, 96, 98, and the output signal at the front right position is output from its “out”. The Furthermore, when a signal at the front center position (channel ch4 signal) is input from “in” to the delay segment 4 (96) and makes one round of the delay loop, each of the delay segments 90, 92, 94, 96, 98 After being delayed by the five delay units 165, the output signal at the front center position is outputted from its “out”, and the signal at the front left position from the “in” (channel ch5 signal) is sent to the delay segment 5 (98). Is input to the delay loop, and the output signal of the front left position is output from the “out” by being delayed by the five delay units 165 of each delay segment 90, 92, 94, 96, 98. .

  As described above, the signal of each channel input to the delay segment is delayed by the five delay units 165 and output from the corresponding delay segment when making one round of the delay loop. Therefore, if the delay time of the five delay units 165 is a period of a specific pitch name of one octave, for example, the pitch name “C”, the peaks of the input signal are superimposed and the pitch of the pitch name “C” is superimposed. It becomes the circuit which resonates with respect to. Thus, the reverberation circuit 200 adjusts the total delay time of the five delay devices 165 to resonate with a specific sound.

  The electronic musical instrument 2 in FIG. 6 includes a reverberation effect adding circuit 1001 including 12 reverberation circuits 200-1 to 200-12 corresponding to the number of pitches of one octave. In each of the reverberation circuits 200-1 to 200-12, the total value of the delay times of the five delay devices 165 is adjusted, and the sound of each pitch name “C, C #,..., B” in one octave is adjusted. It is comprised so that it may resonate with. The inputs from the first delay segment to the fifth delay segment (90, 92, 94, 96, 98) in each of the reverberation circuits 200-1 to 200-12 are connected to the first channel to the fifth channel, respectively. The tone signal up to the channel is configured to be input in common among the twelve circulating reverberation circuits 200-1 to 200-12, and the first delay in each of the circulating reverberation circuits 200-1 to 200-12. From the output section of the fifth delay segment (90, 92, 94, 96, 98) from the segment, the tone signal of the corresponding channel is output as a tone signal in which the circulation reverberation circuit 200 makes one round. Output signals of the same channel of each of the reverberation circuits 200-1 to 200-12 in each of the reverberation circuits 200-1 to 200-12 are added together for each channel. It is configured to be outputted Te, further, and an adder 210 that the musical tone signals of each channel output, and outputs as the corresponding five tone signal is added to each channel input signal. In order to facilitate the understanding of the invention, in FIG. 6, five wirings, that is, wiring for five channels are expressed by describing “\ 5” in the drawing without describing five wirings. Theoretically, five adders are required, but in the figure, they are represented by one adder 210. In addition, the pedal depression information from the pedal depression amount detection unit 115 that detects and outputs the pedal depression amount is input to each delay segment in each of the circulation reverberation circuits 200-1 to 200-12, that is, all the delay segments. ing. When the pedal depression amount is “0”, the damper pedal is not depressed, and when the pedal depression amount is larger than “0”, the damper pedal is depressed and the pedal is fully depressed. Is detected as “1”. Therefore, the pedal depression amount detector 115 outputs a value from “0” to “1” according to the depression amount of the pedal.

(Operation)
For example, when the lowest C key is pressed, information indicating that the lowermost “C” key is pressed is output from the keyboard 110 to the sound source unit 121. In response to this, the sound source unit 121 reads out the corresponding five-channel signals from the waveform memory 125 and outputs them to each of the reverberation circuits 200-1 to 200-12. Each of the reverberation circuits 200-1 to 200-12 receives a signal of 5 channels in common at the same time, but the output from the reverberation circuit 200-1 adjusted so as to resonate with the pitch name “C”. It will be the biggest one. Then, the signals of the same channel in each of the reverberation circuits 200-1 to 200-12 are added together, and the adder 210 adds the output tone signal of each channel to the corresponding channel input signal. The added signal is converted from digital to analog by the D / A converter 141 and emitted from the speaker 151. In this way, it is possible to reproduce the reverberation of the sound corresponding to the pressed key with a spread in the left-right direction and the depth direction. Further, when a plurality of keys are pressed simultaneously instead of one key, the same effect can be obtained by the operation of the corresponding plurality of depth reverberation circuits 200.

  A similar effect can be obtained by separating the LPF 160, the delay unit 165, and the multiplier 165 of a certain delay segment and connecting the separated circuits in the delay loop. Further, as long as the total delay time of the five delay devices 165 is appropriately adjusted, the delay times of the five delay devices 165 are not necessarily the same. The reason why the all-pass filter 80 is used in the delay loop is that it is necessary to adjust the resonance frequency in one round of the delay loop to a decimal order of 1 tap or less. Conventionally, the resonance frequency peak of the delay loop has matched the lowest resonance frequency to the frequency of the lowest pitch name of the piano string, but in the present invention, the higher-order resonance frequency of the delay loop has a noticeable frequency shift. Since it is set to exactly match the fundamental frequency of the piano string in the range, the turbidity of the reverberant sound can be reduced.

(Circulating reverberation circuit 201)
The circulation reverberation circuit 201 shown in FIG. 8 is characterized in that, in the circulation reverberation circuit 200 of FIG. 4, a “Low Cut EQ (low cut equalizer) 210” that functions as a low cut filter that removes low frequency components is provided. However, the position of the all-pass filter 80 in FIG. 4 is changed. A multiplier 211 having a coefficient “k1” is connected to the output of the low-cut equalizer 210, and a signal input to the low-cut equalizer 210 is also connected to a multiplier 212 having a coefficient “1-k1”. The output of the multiplier 211 and the output of the multiplier 212 are configured to be added by an adder 213, and this adder 213 is connected in the delay loop. And the coefficient control part 220 which changes and controls coefficient "k1" and "1-k1" based on pedal depression information is provided.

  When the damper pedal is depressed, the coefficient control unit 220 decreases the value of the coefficient “k1”. As a result, the coefficient “1-k1” is increased, and the low-cut equalizer 210 is substantially bypassed. On the other hand, when the damper pedal is not depressed, the coefficient control unit 220 increases the value of the coefficient “k1”. As a result, the coefficient “1-k1” becomes small, and the low-cut equalizer 210 is substantially activated. As a result, in the case where the attenuation in the delay loop is adjusted by the coefficient change, it is possible to eliminate the fact that the fundamental sound component is slow to decay when the damper pedal is not depressed, and is unnatural.

(Damper release noise circuit 320)
FIG. 7 is a configuration diagram of a damper release noise circuit 320 that generates damper release noise when the damper pedal is depressed. The waveform memory 125 stores waveform data obtained by actually obtaining a damper release noise sound generated when the pedal is depressed. This damper release noise sound includes a periodic component of the sound generated by the string when the damper is released from the string, and has redundancy, so this noise component is detected and removed as a noise sound. . First, when the pedal depression amount detection unit 115 detects that the damper pedal is depressed, in response to this, the sound source 122 reads the damper release noise from the waveform memory 125 and outputs it. Then, as will be described later, the pedal depression speed detector 300 outputs a depression speed coefficient V that is a coefficient corresponding to the pedal depression speed. Then, the multiplier 310 outputs the result of multiplying the damper release noise and the stepping speed coefficient V. This output is converted from digital to analog by the D / A converter 140, and damper release noise is emitted from the speaker 150. Thus, the damper release noise when the damper pedal is depressed can be reproduced realistically.

  Now, the pedal depression speed detection unit 300 sets a constant, for example, “1” in the memory 301 when the pedal depression amount reaches a first value. Then, this constant is multiplied by a coefficient a smaller than 1 every sampling time. Then, if the value when the pedal depression amount becomes the second value is determined, this corresponds to the depression speed. FIG. 9 is an explanatory diagram showing this state. Assuming that the stepping speed V0 at the time of the first constant “1”, the speeds of V1, V2 increase as the squares of a, a,. ... Vn. Therefore, the depression speed of the damper pedal can be obtained by a simple method. When the damper pedal is provided with two contacts, the constant “1” is set in the memory 301 when the first contact is turned on from the depression start state, and then every sample time until the second contact is turned on. When the second contact is turned on by multiplying by a, the multiplication value may be taken out from the memory 301 to obtain a coefficient V corresponding to the stepping speed. Note that the damper release noise circuit 320 shown in FIG. 7 can be provided in the reverberation effect addition circuits 1000 and 1001 in FIG. 2 and FIG.

  As described above, the present invention can provide a reverberation effect adding device that can add effects by simulating the reverberation effect of an acoustic piano more realistically.

1 is a configuration diagram of a depth reverberation circuit 100. FIG. It is explanatory drawing of the electronic musical instrument 1 to which the depth reverberation circuit 100 is applied. It is explanatory drawing of recording of the musical tone signal of an acoustic piano. 2 is a configuration diagram of a reverberation circuit 200. It is a block diagram of a delay segment. It is explanatory drawing of the electronic musical instrument 2 to which the circulation reverberation circuit 200 is applied. It is a block diagram of the circuit which simulates pedal release noise. FIG. 10 is a configuration diagram of a modified example of the circulation reverberation circuit 200. It is explanatory drawing of operation | movement.

Explanation of symbols

10 LPF (low pass filter)
20 LPF (low pass filter)
30 Delay R
35 Delay L
50 multiplier 55 multiplier 60 all-pass filter 70 LPF (low-pass filter)
80 All-pass filter 90 Delay segment 92 Delay segment 94 Delay segment 96 Delay segment 98 Delay segment 100 Depth reverberation circuit 110 Keyboard part 115 Pedal depression amount detection part 120 Sound source part 125 Waveform memory 140 A / D converter 150 Speaker 160 LPF (low-pass filter) )
165 Delay Device 200 Circulating Reverberation Circuit 210 Low Cut EQ (Low Cut Equalizer)
211 Multiplier 212 Multiplier 213 Adder 300 Pedal depression speed detection unit 1000 Reverberation effect addition circuit 1001 Reverberation effect addition circuit

Claims (3)

During the delay loop connects the first delay device and a second delay unit in a loop and one or more low-pass filters, and one or more all-pass filter, and one or more attenuated coefficient multiplier, Are equipped with twelve depth reverberation circuits that are connected to form the delay loop, which is the number of pitches in one octave,
In each depth reverberation circuit, the sum of the delay time of the first delay device and the delay time of the second delay device is set to a value corresponding to the period of the sound of each pitch name,
The near side input signal recorded at a predetermined position on the near side of the acoustic piano is commonly input to the first delay unit in each depth reverberation circuit, and the second delay unit in each depth reverberation circuit receives the acoustic piano's input signal. The back side input signal recorded at a predetermined position on the back side is configured to be input in common, and each of the near side input signal and the back side input signal in each depth reverberation circuit is a delay loop of each depth reverberation circuit. Are output as a near-side output signal and a back-side output signal, respectively, and are configured so that the near-side output signals and the back-side outputs of each depth reverberation circuit are added together,
A first adder for adding the near side input signal and the near side output signal; and a second adder for adding the back side input signal and the back side output signal. A reverberation effect addition circuit. A first low-pass filter, a first delay unit, a first attenuation coefficient multiplier, a second low-pass filter, an all-pass filter, a second delay unit, and a second attenuation coefficient multiplier; It has 12 depth reverberation circuits connected in a loop, which is the number of 1 octave pitch names,
In each depth reverberation circuit, the sum of the delay time of the first delay device and the delay time of the second delay device is set to a value corresponding to the period of the sound of each pitch name,
The near side input signal recorded at a predetermined position on the near side of the acoustic piano is commonly input to the first delay unit in each depth reverberation circuit, and the second delay unit in each depth reverberation circuit receives the acoustic piano's input signal. The back side input signal recorded at a predetermined position on the back side is configured to be input in common,
The front side input signal and the back side input signal in each depth reverberation circuit circulate around the loop of each depth reverberation circuit, respectively, and are output as the front side output signal and the back side output signal, respectively, before the depth reverberation circuit. The side output signals and the back side output signals are added together,
A first adder for adding the near side input signal and the near side output signal; and a second adder for adding the back side input signal and the back side output signal. A reverberation effect addition circuit. A delay segment having a delay unit, an attenuation coefficient multiplier, a low-pass filter, an output unit provided downstream of the low-pass filter, and a sound input unit of a certain channel provided downstream of the low-pass filter includes a plurality of channels (first channel). A reverberation circuit in which a number of channels of m tone signals from channel to m-th channel (m is an integer of 2 or more) connected in series and an all-pass filter connected in a loop form a sound of 1 octave. It has 12 names,
In each cyclic reverberation circuit, set the total value of the delay times by the delay segments of the delay segment for the number of channels (m) to correspond to the period of the sound of each pitch name,
Musical sound signals from the first channel to the m-th channel, which are reproduction signals of signals recorded at m points of the acoustic piano, are input to the first to m-th delay segment input sections in each circulation reverberation circuit. The twelve cyclic reverberation circuits are input in common, and the outputs from the first delay segment to the m-th delay segment in each cyclic reverberation circuit respectively A musical sound signal is output by circulating the reverberation circuit, and the output signals of the same channel in each of the twelve circular reverberation circuits are added and output for each channel.
A reverberation effect adding circuit comprising: an output circuit for adding the output tone signals of each channel to the corresponding channel input signals and outputting them as m tone signals .

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