JPH02268100A - Audio equipment - Google Patents

Abstract

PURPOSE:To attain listening of medium and high frequency band and a low frequency band even by a conventional speaker in the same time by retarding an audio signal component of a medium and high frequency band timewise from that of a low sound frequency. CONSTITUTION:A function switch 4 selects an audio signal from an analog or a digital device 1 or 2 and in the selection of the device 1, a signal from the device 1 is inputted directly to a low frequency compensation circuit 5 and the signal from the device 2 is inputted to a compensation circuit 5 via an A/D converter 3. The compensation circuit 5 sets the audio signal so that the delay time of the audio signal component of the medium and high frequency hand larger than the delay time of the low frequency audio signal component. The signal compensated by the circuit 5 is sent to a speaker via a D/A converter 6 and the sound whose low frequency sound delay is compensated is given to a listener.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an audio device that outputs audio signals.

[Prior Art] Generally speaking, an audio signal output from an audio device such as an audio amplifier is perceived by a person who listens to the audio signal in such a way that the low frequency audio signal component is higher than the middle and high frequency audio signal component. arrive late. In other words, when listening to the audio signal with a speaker for mid-high range and a low-range speaker installed on the same plane, the low-range sound heard from the low-range speaker is louder than the low-range sound heard from the mid-high range speaker. It will be heard later than the mid-high range sounds that can be heard.

Therefore, in order to eliminate the above-mentioned disadvantages, a speaker shown in FIG. 6 has been proposed. In the same figure, a speaker (woofer) SP for low range, a speaker (woofer) for mid range
Regarding the sound radiation direction (horizontal direction) of each squawker) SP2 and high-frequency speaker SP (tweeter), the mounting position of Woo/S S P + is in front of the mounting position of squawker SPz, and the mounting position of the squawker The mounting position of SP is set to be in front of the tweeter SP3.

According to the speaker with this configuration, since the woofer SP is installed closer to the listener than the squawker SPz and the tweeter SP3, the time delay of the low-frequency audio signal component with respect to the mid-high frequency audio signal component is reduced. compensated,
The listener can hear sounds in the low and mid-high ranges at the same time without any time lag.

[Problem to be solved by the invention]

According to such a conventional configuration, the structure of the speaker becomes complicated, which is disadvantageous in terms of vibration. In addition, in front of the tweeter SP3 and Squawka SPz, there is Uno\SP, and Squawka SPz.
Since the cabinet that houses the speaker protrudes, there is a problem in that mid-high range sounds emitted from the squawker SPz and the tweeter SP3 are affected by the protruding cabinet.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an audio device that allows middle and high frequencies and low frequencies to be heard at the same time without any time delay even when driving a general speaker.

[Failure to solve the problem]

The present invention has been made in view of the above-mentioned object, and is characterized by comprising means for time-delaying mid-high frequency audio signal components relative to low frequency audio signal components.

[Function] In the above configuration, the middle and high frequency audio signal components are delayed with respect to the low frequency audio signal components by the delay means. Therefore, the audio signal components in the low range are relatively advanced in time compared to the audio signal components in the middle and high ranges, and the sound in each of the above bands is emitted from the speaker without any time delay in terms of frequency.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is a digital source device that outputs digital audio signals such as a compact disc player (CD player), 2 is an analog source device that outputs analog audio signals such as a tape deck or tuner, and 3 is the analog source device 2. 4 is an A/D converter for converting analog signals into digital signals, and 4 is the digital source device 1.
and A/D converter 4, 5 is a low-frequency compensation circuit that is a feature of the present invention, and 6 is a D/D converter that converts the digital audio signal from the low-frequency compensation circuit 5 into an analog signal. It is an A converter.

In the above configuration, each audio signal from the digital source device 1 or the analog source device 2 is selected by the function switch 4, and the digital source device 1
When the analog source device 2 is selected, the digital audio signal is directly input to the low frequency compensation circuit 5, and when the analog source device 2 is selected, the signal converted to a digital audio signal by the A/D converter 3 is input to the low frequency compensation circuit 5. be done.

The low frequency compensation circuit 5 is composed of a digital filter,
As shown in FIG. 2, the characteristics of the delay time of an input digital audio signal with respect to its frequency are set. In other words, the delay time of the mid-high range audio signal component is set to be larger than the delay time of the low-range audio signal component, so that the low range audio signal component becomes the mid-high range audio signal component. I am trying to make time advance relative to the other. The audio signal from the low frequency compensation circuit 5 is converted into an analog audio signal by a D/A converter 6, power amplified by a power amplifier (not shown), and then input to a speaker to drive it. At this time, even if the analog audio signal is driven by a general speaker in which speakers for each band such as a woofer and a tweeter are arranged on the same plane, as described above (low frequency compensation circuit 5 Since the audio signal components in the range are advanced in time relative to the audio signal components in the middle and high ranges, the delay of the low range sound relative to the middle and high ranges emitted from the speaker is compensated for.

Therefore, the sound from the speaker reaches the listener at the same time without any time delay in terms of frequency.

Next, the low frequency compensation circuit 5 will be explained. The transfer function of an all-pass filter that passes all bands of the digital signal is S2-S+(ωr)'. Here, ωr is the resonance angular frequency (radian/second). Therefore, if we convert this equation (1) again, we get: Therefore, from equation (2), the all-pass filter has a configuration as shown in FIG. In the figure, 71 is a delay device, Ao
, A+ , Az , B 0. Bz is a coefficient multiplier,
51 is an adder, 5□ is a subtracter, and the group delay characteristics thereof are as shown in FIG.

Therefore, by appropriately setting the resonant frequency pole ωr and Q in equation (1), it is possible to compensate for the above-mentioned low-frequency digital audio signal component.

Furthermore, if a plurality of all-pass filters shown in Fig. 3 are connected in series and the ωr of each filter is set to be different from each other, the overall frequency characteristic becomes as shown in Fig. 5(a), and as a result, as a low-frequency compensation circuit, As shown in FIG. 5(b), it is possible to obtain a characteristic in which the delay time is flat in the middle and high frequencies, and in the low frequency range, the delay time decreases as the frequency decreases (the same characteristics as in FIG. 2).

The digital filter shown in FIG. 3 can be easily constructed by using a digital signal processor (DSP), and the delay time and frequency can also be easily set to desired values.

Furthermore, although the above embodiment has shown a configuration in which the digital audio signal is compensated for the low frequency range, the analog signal may be directly compensated for the low frequency range.

〔effect〕

As described above, according to the present invention, even when driving a general speaker, the time delay in the low frequency range is compensated.
The listener can hear sounds at the same frequency and time from the speaker.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing frequency versus lead time and delay time characteristics of the low frequency compensation circuit of FIG. 1, and FIG. 3 is an embodiment of the low frequency compensation circuit. Figure 4 shows the third
Figure 5 (a), (b) shows the group delay characteristics of the circuit.
) is a diagram showing another group delay characteristic of a low-frequency compensation circuit, and FIG. 6 is a diagram showing a conventional speaker that takes low-frequency compensation into consideration. 1... Digital source device, 2... Analog source device, 5... Low frequency compensation circuit.

Claims (1)

[Claims] 1. An audio device comprising: means for time-delaying mid-high frequency audio signal components relative to low frequency audio signal components.