JPH0215079B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a device that artificially adds reverberation to a music signal, etc., and involves superposition (convolution calculation) of delayed signals to create a reverberation signal based on input signal data sequentially written into a delay memory. ) by performing a plurality of sets of reverberation signals, it is possible to simultaneously obtain a plurality of types of reverberation signals with one delay memory. When artificially adding reverberation to music signals, etc., the most direct electronic method is to express it as a superposition of signals with various time delays from the direct sound, corresponding to the impulse response of a virtual room. It's a method. As shown in FIG. 1a, this method uses a delay memory 1 having a multi-tap, and sends a delayed signal from each tap to an amplitude adjuster 2-1.
2-2, . . . , 2-n by an adder 3. In the apparatus shown in FIG. 1a, a reverberant signal xout= _o 〓 ⁱ⁼¹ x _i ·g _i is obtained as the output xout. where x _i is the input signal
The signal obtained by delaying x _io by time τ _i , g _i is the signal of each amplitude adjuster 2-
This is a gain of 1, 2-2, . . . , 2-n, that is, a weighting value for each delayed signal x _i . The echo time pattern of the device of FIG. 1a is shown in FIG. 1b. When adding artificial reverberation, when trying to obtain a reverberation that is closer to nature (such as an actual hall),
A plurality of reverberation signals are spatially arranged with respect to an input signal (for example, the sound of one musical instrument). For example, a method of multi-channeling such as 2 channels or 4 channels can be considered. however,
In this case, if the structure shown in FIG. 1A is simply constructed using a plurality of series, the equipment will be doubled or quadrupled, resulting in an increase in cost. This invention has been made in view of the above-mentioned points, and aims to provide a reverberation adding device with simplified equipment by making it possible to simultaneously extract multiple types of reverberation signals by sharing a delay memory. It is. According to this invention, input signal data is sequentially captured in a data memory (delay memory) at a fixed sampling period, and a plurality of delayed input signal data corresponding to each delay time of an impulse response of a reverberation characteristic are stored at each sampling period. A plurality of types of impulse responses are retrieved from the data memory in a time-division manner, and each gain data of each impulse response is applied to each delayed input signal data retrieved from the data memory, and each impulse response is retrieved for each sampling period. A convolution operation is performed, and a plurality of operation results obtained for each sampling period are output as each reverberation signal. Note that the delayed data retrieval means in the present invention corresponds to an output tap if the data memory is a shift register, for example, and corresponds to a circuit that supplies a memory address if it is a RAM. Embodiments of the present invention will be described below with reference to the accompanying drawings. Regarding the configuration of the delay memory, in the case of analog signals, a charge transfer element such as a BBD or CCD can be used, and in the case of digital signals, a digital memory that is program-controlled using a shift register or RAM can be used. However, in the following embodiments, a method using RAM, which has a large degree of freedom in terms of configuration and allows easy setting and changing of parameters (delay time and gain), will be described. In FIG. 2, the delay memory 5 has 2n taps with delay times τL ₁ , τL ₂ , . . . , τL _o , τR ₁ , τR ₂ , . . . , τR _o . Here, for the purpose of obtaining reverberant signals of two left and right channels, τL ₁ ,
τL ₂ ,...,τL _n are used for the left channel, τR ₁ ,
τR ₂ , ..., τR _o are used for the right channel.
That is, the input signal x _io is divided into times τL ₁ , τL ₂ , ..., τL _o
The delayed signals xL ₁ , xL ₂ , ..., xL _o have a gain of
Amplitude adjuster 6-1, 6- for gL ₁ , gL ₂ , ..., gL _o
After _being weighted _by 2 ^, _. In addition, signals xR ₁ , xR ₂ , ..., which are obtained by delaying the input signal x _io by time τR ₁ , τR ₂ , ..., τR _o
xR _o is weighted by amplitude adjusters 8-1, 8-2, ..., 8-n with gains of gR ₁ , gR ₂ , ..., gR _o , respectively, and then combined by an adder 9, and xR _put = _o 〓 ⁱ⁼¹ xR _i・gR _i (2) Output. Note that the delay times τL ₁ , τL ₂ ,
…, τL _o , τR ₁ , τR ₂ , …τR _o and gain gL ₁ ,
The values of gL ₂ , ..., gL _o , gR ₁ , gR ₂ , ..., gR _o are set by a simulation of a room with the expected reverberation characteristics. According to the above configuration, one delay memory 5
Since it is possible to obtain two channels of reverberant signals, the configuration can be simplified and costs can be reduced compared to the case where a delay memory is used for each reverberant signal. Although FIG. 2 shows the case where reverberant signals of two channels are extracted, it is also possible to extract reverberant signals of more channels. Next, a specific example of the configuration of the reverberation adding device shown in FIG. 2 will be explained. In FIG. 3, the parameter memory 10 is 0 to
It has 2n+1 addresses up to 2n, and each parameter of delay time data and gain data is stored in each address. The parameters stored in each address are shown in the table below.

【table】

Claims (1)

[Claims] 1. A data memory that sequentially captures input signal data at a fixed sampling period; delay data retrieval means for retrieving impulse responses from the data memory in a time-division manner; A reverberation adding device comprising: a calculation unit that performs a convolution calculation on a response; and an output unit that outputs a plurality of calculation results obtained from the calculation unit for each sampling period as each reverberation signal.