JPS6410840B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an electronic musical instrument having an overdubbing function capable of superimposing several pre-recorded audio signals and digitally recording them again as a sound source signal.

[Background of the invention]

2. Description of the Related Art Conventionally, electronic musical instruments have been considered that have an overdubbing function in which several pre-recorded audio signals are superimposed and digitally recorded again as a sound source signal.

For example, Japanese Patent Application Laid-Open No. 166698/1984 discloses such a prior art. In this prior example, new musical tone data (waveform data) is simply stored redundantly, that is, synthesized, with musical tone data (waveform data) that has already been stored in the musical tone data memory; No consideration has been given to reading out one or more existing waveforms in different states and combining them to obtain a new waveform signal, and as a result, only an unsatisfactory performance effect can be obtained.

[Purpose of the invention]

The present invention has been made in view of the above points, and it is an object of the present invention to provide an electronic musical instrument that is simple, easy to operate, and musically satisfying.

[Key points of the invention]

In order to achieve the above-mentioned object, the present invention reads at least two digital waveform signals having the same or different waveforms having different frequencies from a storage means, and synthesizes the read digital signals digitally or analogously. The main point is to record digitally again in a storage medium.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to an embodiment shown in the drawings. FIG. 1 shows the circuit configuration of this embodiment, where an input signal (IN) is suitably amplified by an input amplifier 1 and then supplied to an analog adder circuit 2.
Further, a filter 3 removes high-frequency components, and then a sample/hold circuit (S/H) 5 samples the signal at an appropriate sampling frequency and supplies it to an A/D converter 6. The A/D converter 6 converts the input analog signal into a corresponding digital signal and supplies it to the sound generation control section 8.

This sound generation control unit 8 has, for example, four waveform readouts and
A write channel is provided, and waveform signals can be written to or read from the waveform memory 7 independently. The specific structure of this sound generation control section 9 is described in the above-mentioned Japanese Patent Application No. 167119/1982, so a detailed explanation thereof will be omitted.

This sound generation control unit 8 operates based on control from a CPU 9 consisting of a microcomputer, etc., and corresponds to the four waveform read/write channels of this sound generation control unit 8, so that up to four A digital signal corresponding to the sound is read from the waveform memory 7, applied to the D/A converter 10 in a time-divisional manner, and then supplied to sample and hold circuits (S/H) 11a to 11d.

These sample and hold circuits 11a to 11d
performs a sampling operation at each time-division processing channel time using timing signals t ₁ to _{t 4} as described later.

And this sample and hold circuit 11a~
The voltage signal held in 11d is supplied to VCFs (voltage controlled filters) 12a to 12d in a corresponding manner. For each of these VCFs 12a to 12d,
Voltage signals FCV1 to FCV4, which will be described later, are supplied,
Filtering processing is performed independently according to the voltage signals FCV1 to FCV4.

The VCFs 12a to 12d then send filtered analog waveform signals to VCAs (voltage controlled amplifiers) 13a to 13d.

The amplification factors of the VCAs 13a to 13d are independently controlled by the supplied control voltage signals ACV1 to ACV4, and the output level or volume envelope of the waveform signals supplied from the VCFs 12a to 12d is determined.

Then, the output signals of the VCAs 13a to 13d are sent out to the outside as outputs OUT1 to OUT4 of the respective channels, and after being appropriately amplified, are emitted as sound signals. Also, this VCA
The outputs of 13a to 13d are sent to the analog adder circuit 14.
is supplied to the mixer, mixes it, and mixes it to the mixer output.
It is also possible to export it externally as OUTMIX.

Also, it corresponds to the fourth channel mentioned above.
The output of the VCF 12d and the output of the analog adder circuit 14 are supplied to an analog switch 15 which performs a switching operation according to a control signal from the CPU 9 mentioned above.

This analog switch 15 selects the output of the VCF 12 d and the output of the analog adder circuit 14 and supplies them to a VCA (voltage controlled amplifier) 16 .

In VCA16, the supplied control voltage signal ACV
0, and the analog adder circuit 2 described above
The company will provide feedback and supply to customers.

Therefore, the external sound signal supplied via the input amplifier 1 and the waveform signal obtained by reading out the waveform memory 7 can be mixed in this analog adder circuit 2 and supplied to the waveform memory 7 again. .

Reference numeral 4 in the figure denotes a keyboard/display unit consisting of a keyboard with performance keys and various control switches, and a liquid crystal display panel that displays various statuses.The CPU 9 and this keyboard/display unit 4 exchange data. I do.

In addition, this CPU 9 uses software processing to
Each of the above-mentioned control signals FCV1 to FCV4, ACV1 to
To generate ACV4, ACV0 (hereinafter collectively referred to as control signals CV), digital signals are
The signals are supplied to the A converter group 17 and converted into respective voltage signals.

This D/A converter group 17 may have a number of D/A converters corresponding to the number of control signals CV, or one D/A converter may be used in a time-sharing manner, The required number of control signals CV may be obtained in combination with a sample and hold circuit.

Next, the operation of this embodiment will be explained. FIG. 2 shows the time division processing state of multiple channels of the sound generation control unit 8 and the sample and hold circuits 11a to 11d.
As mentioned _above , in this embodiment, _four waveform read/write channels are realized in a time division configuration, and each waveform read/write channel is It is now possible to selectively specify whether to perform read processing or write processing for each input channel.
In the state shown in FIG. 2, the waveform signal obtained through the filter 3, sample-and-hold circuit 5, and A/D converter 6 is written into the waveform memory 7 by the processing of channel 1 (ch ₁ ). It has become
The other channels 2 to 4 (ch _{2 to 4} ) are capable of reading digital waveform signals in predetermined areas from the waveform memory 7.

Further, the timing signals t ₁ to _{t 4} described above are high at times corresponding to the respective channels (ch _{1 to 4} ).
Sample and hold circuits 11a to 11d output analog waveform signals output from the D/A converter 10 at each channel time.
, it will be sampled and held from then on.

FIG. 3 shows how the waveform memory 7 is divided into areas, so that, for example, N pieces of waveform information can be recorded in variable lengths. Each waveform read/write channel of the sound generation control unit 8 is designed so that an area to be read/written can be specified independently.
For example, channels 2, 3, and 4 read tones 1, 2, and 3 in FIG.
2d, processing is controlled by VCA13b to 13d, analog addition circuit 14, switch 15, VCA16
is supplied to the analog adder 2 via the
The signal is inputted via the hold circuit 5 and the A/D converter 6, and is processed by channel 1 and recorded in the waveform memory 7 again as tone N. That is, it is also possible to perform overdubbing processing.

Further, the CPU 9 sends a switching signal to the analog switch 15, and the waveform signal read out from the waveform memory 7 by the processing of channel 4 is further applied to the VCA 16 via the sample/hold circuit 11d and VCF 12d. The waveform signal thus obtained is supplied to the analog adder 2, mixed with the external sound signal in the same manner as described above, and then written into a predetermined area of the waveform memory 7. You can also do it.

Next, processing mainly performed by the CPU 9 in the overdubbing mode will be described in detail with reference to the flowchart shown in FIG.

By operating the switch on the keyboard/display section 4
When the CPU 9 is designated to overdubbing mode, first, in step _S1 , the keyboard/display is used to determine which scale frequency the waveform signal already stored in the waveform memory 7 is to be read out. Check whether or not the keyboard of section 4 has been operated.

That is, in this embodiment, the frequency of the musical tone to be generated is specified by key operations on the keyboard, and the waveform signal recorded in the waveform memory 7 has a specified high-frequency scale. If so, it will be output from the waveform memory 7 at a high readout rate,
If a bass scale is specified, it will be output from the waveform memory 7 at a low readout rate.

Then, if there is a key input in step _S1 , Yes
Make a judgment and move to step _S2 . Step S ₂
Now, the number of the tone to be read from the waveform memory 7 specified on the keyboard/display section 4, along with the scale specified by the key operation, is sent to the CPU 9.
remembers. The CPU 9 also stores information for determining the corresponding volume. Then, the process moves to step _S3 .

Even if a negative determination is made in step _S1 , the process proceeds to step _S3 . Step _S3 is a step to check whether a trigger signal to actually start recording has been supplied from the keyboard/display section 4, and if it has not been applied yet, step _S1 is executed again.
Return to step S ₁ → S ₃ or step S ₁ →
Repeat S ₂ → S ₃ to enter standby state.

Therefore, when multiple keys are operated on the keyboard, up to three scales can be assigned to channels 2, 3, and 4, and if different tone numbers are specified for each, different tones can be assigned. If the waveform signal is in a specified scale and the same tone number is specified in each channel, the waveform signal of the same tone will be played in a different specified scale,
Moreover, it will be overdubbed with a different volume.

If there is a trigger input in step _S3 above, a Yes determination is made and the process moves to step _S4 . In step _S3 , a trigger input may be automatically given to the CPU 9 when the input signal (IN) exceeds a predetermined level, and the process may proceed to step _S4 .

In step _S4 , the tone number and scale information saved by the CPU 9 are supplied to the sound generation control section 8, and the area of waveform data to be read from the waveform memory 7 is specified for each waveform read/write channel. Specify the scale.

Next, proceeding to step _S5 , the CPU 9 sends a digital signal for generating each control signal to the D/A converter group 17, generates a voltage control signal CV, and outputs a voltage control signal CV to each VCF 12a to 12d and VCA 13a.
~13d, the VCA 16 is made to send out the respective control signals CV.

Further, the CPU 9 provides a switching signal to the analog switch 15 so as to supply the mix waveform signal from the adder circuit 14 to the VCA 16 . Then proceed to step S ₆ and use channel 1 to
CPU9 starts actual recording. At this time,
A designated channel among channels 2 to 4 operates to generate a predetermined acoustic signal by reading waveform data from the waveform memory 7, respectively.

When the input processing is completed, the CPU 9 enters the end state and returns to the main routine processing (not shown).

As described above, in this embodiment, the four waveform read/write channels of the sound generation control unit 8 are configured to independently read and write waveform signals, and at least two channels are used to read and write waveform signals in the waveform memory. The same or separate digital signals are read out from VCF12a to 12d and VCA13.
After controlling tone and volume independently in a to 13d,
Since the signals are mixed and written as a new sound source signal to the waveform memory 7 using a specific channel, it is possible to enhance the overdubbing function, which is also desirable from a musical perspective.

Also, using up to three of the four waveform read/write channels, waveform data is read from the waveform memory 7, and if necessary, this reproduced waveform data and the input waveform signal (IN) are synthesized to generate a sound source. Since it can be used as waveform data, various modes of overdubbing can be performed.

In addition, by dividing the waveform memory 7 into multiple areas and using it, it is possible to write the waveform signal obtained as a result of overdubbing to an area different from the area where the original waveform signal is recorded, and the original waveform signal It becomes possible to overdub without erasing the data.

Further, the volume level can be independently set for each waveform signal obtained by reading from the waveform memory 7 through a plurality of waveform read/write channels using the VCAs 13a to 13d.

Also, the same waveform data can be read out from the same memory area at different scale frequencies using multiple waveform read/write channels, and the VCA13a~
13d allows synthesis while changing the synthesis ratio.

In addition, in the above-mentioned embodiment, VCF12
Although the timbre and volume are variably controlled by the VCAs a to 12d and VCAs 13a to 13d, the timbre and volume can be controlled using digital filters, digital multipliers, etc.
Variable control such as volume or envelope may also be performed. Further, other processing may be performed on the waveform signal.

In addition to the circuit configuration of the sound generation control section 8, which configures multiple waveform read/write channels by time-sharing processing as in the above embodiment, separate hardware, that is, the same circuit configuration for the number of channels, is used. A plurality of waveform read/write channels may be provided by using a plurality of waveform read/write channels.

Further, among the plurality of channels, a specific channel is designated as a write-only channel for writing waveform signals into the waveform memory 7, and the other channels are designated as
It may also be a read-only channel for reading waveform signals from the waveform memory 7. In the present invention, “waveform readout/
The term ``write channel'' refers to any channel that enables only one or both of read and write operations.

〔Effect of the invention〕

As described above, the present invention can provide an electronic musical instrument that is simple, has good operability, and is musically preferable.

In particular, it is possible to read at least two digital waveform signals having the same waveform or different waveforms with different frequencies from the storage means, synthesize them digitally or analogously, and record them as a new sound source waveform in the storage means. If the frequency is made small, a detune effect can be obtained, and if the frequency is made large, an ensemble-like sound can be easily obtained.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a circuit configuration diagram thereof, FIG. 2 is a time chart for explaining its operation, FIG. 3 is a diagram showing a storage state of a waveform memory, and FIG. FIG. 4 is a flowchart for explaining the operation of the embodiment. 2...Analog addition circuit, 4...Keyboard/
Display section, 6... A/D converter, 7... Waveform memory, 8... Sound generation control section, 9... CPU, 10...
D/A converter, 12a to 12d...VCF, 13
a to 13d...VCA, 14...analog adder,
17...D/A converter group.

Claims (1)

[Scope of Claims] 1. Storage means for storing a digital waveform signal; Frequency designation input means for designating and inputting at least two mutually different frequencies as frequencies of the digital waveform signal stored in the storage means; a frequency storage means for storing at least two mutually different frequencies inputted by the frequency designation input means; reading means for reading digital waveform signals representing at least two identical waveforms having mutually different frequencies or at least two different waveforms having respective mutually different frequencies; a synthesizing means for synthesizing at least two waveform signals each having a different frequency corresponding to the two digital waveform signals to obtain a synthesized waveform signal; 1. An electronic musical instrument comprising means for supplying the signal to a storage means and storing it as a new digital waveform signal.