JPH07244485A - Electronic keyboard musical instrument - Google Patents

Abstract

PURPOSE:To obtain localization close to a grand piano, etc., without deteriorating pitch characteristics of speakers while using the high-register and low- register keyboard side speakers having nearly the same output characteristics by arranging a specific cabinet for a low register range. CONSTITUTION:The electronic keyboard musical instrument is constituted by arranging the speakers 53 and 55 which have nearly the same output characteristics on the low-register keyboard side and high-register keyboard side; and a through hole 47a on the low-register keyboard side of a rack plate 47 is bored in the reverse surface of the rack plate 47 and the cabinet 57 for the low-register range which increases the sound volume of the low-register range of the low-register keyboard side speaker 53 is arranged. A duct 61 is formed in the bottom surface 57a of the low-register range cabinet 57, which is constituted into a bass-reflex type cabinet. Therefore, a sound wave from the front surface of the diaphragm 53a of the low-register side speaker 53 is inverted in phase by the duct 61 and radiated downward from the duct 61. Consequently, the sound volume of the low-register range of the low-register keyboard side speaker 53 is increased to obtain the localization which is closer to a grand piano, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic keyboard instrument such as an electronic piano and an electronic organ, and more particularly to an electronic keyboard in which speakers having substantially the same output characteristics are arranged on the bass and treble keyboard sides. Regarding musical instruments.

[0002]

2. Description of the Related Art Conventionally, in an electronic keyboard musical instrument such as an electronic piano, speakers having substantially the same output characteristics are arranged on a bass keyboard side and a treble keyboard side, and bass is mainly a speaker on the bass keyboard side (hereinafter referred to as a bass speaker). That is, the treble is localized mainly by reproducing the treble from the treble keyboard side speaker (hereinafter referred to as the treble side speaker).

FIGS. 4 and 5 show an electronic keyboard musical instrument of this kind. In these drawings, reference numeral 11 indicates the keyboard 1.
The main body case in which 3 is arrange | positioned is shown. Both sides of the main body case 11 are supported by side plates 15, and a pedal base 17 is horizontally bridged below the side plates 15.

The main body case 11 is formed of an upper panel 19, a back panel 21, a shelf board 23, etc., and a bass speaker 25 and a bass speaker 25 having substantially the same output are provided on the bass keyboard side and the treble keyboard side of the shelf board 23. A high-pitched speaker 27 is arranged.

The vibrating plates 25a, 27a of the low-pitched speaker 25 and the high-pitched speaker 27 are arranged opposite to the through holes 23a, 23b formed in the shelf 23.
In this electronic keyboard instrument, the shelf plate 23 is a baffle plate, and sound waves generated from the diaphragms 25a, 27a of the low-pitched speaker 25 and the high-pitched speaker 27 are generated by the diaphragm 25.
a and 27a are radiated to the front surface and the rear surface, respectively.
The sound waves from the rear surfaces of 5a and 27a are mainly emitted through the gaps formed in the main body case 11 or through the gaps.

[0006]

However, in such a conventional electronic keyboard musical instrument, since the low-pitched speaker 25 and the high-pitched speaker 27 have the same output characteristics, the strings are actually played by the keyboard. There is a problem that it is difficult to obtain a localization close to that of a grand piano or the like because the volume of the low range is low compared to a grand piano or the like that produces a sound by hitting.

That is, in general, in this type of electronic keyboard instrument, in order to obtain a good stereo effect in the mid-high range, a speaker having the same output characteristic is used as the bass speaker 25 and the treble speaker 27. Therefore, in order to increase the volume of the bass range, the diaphragm 2 of the bass side speaker 25 is increased.
When trying to increase 5a, it is necessary to increase the size of the diaphragm 27a of the high-pitched speaker 27.
The treble characteristic of No. 7 deteriorates, and it becomes difficult to obtain a predetermined treble range sufficiently.

The present invention has been made to solve such a conventional problem, and uses a speaker on the bass keyboard side and a speaker on the treble keyboard side having substantially the same output characteristics, while using the speaker without deteriorating the treble characteristics of the speaker. It is an object of the present invention to provide an electronic keyboard instrument that can obtain a localization close to that of a piano or the like.

[0009]

According to another aspect of the present invention, there is provided an electronic keyboard instrument having speakers having substantially the same output characteristics on the bass keyboard side and the treble keyboard side of the upper surface of the shelf of the main body case in which the keyboard is arranged. In the electronic keyboard musical instrument, wherein the diaphragm of the speaker is arranged so as to face the through-holes formed on the bass keyboard side and the treble keyboard side of the shelf board, the bass keyboard of the shelf board is provided on the lower surface of the shelf board. To the through hole on the side,
The bass cabinet is arranged to increase the bass volume of the bass keyboard speaker.

According to a second aspect of the present invention, in the electronic keyboard instrument according to the first aspect, the volume of the bass cabinet is 50 Hz to 50 Hz.
It is set so that the volume of the low-pitched sound of the frequency of 200 Hz is increased.

[0011]

In the electronic keyboard instrument according to the first aspect of the present invention, the volume of the bass range of the bass keyboard side speaker is increased by the bass range cabinet, resulting in a localization closer to that of a grand piano or the like.

Further, since speakers having substantially the same output characteristics are used for the bass keyboard side and the treble keyboard side speakers, the stereo effect in the middle and high range is improved.
In the electronic keyboard musical instrument according to the second aspect, the volume of the bass sound having a frequency of 50 Hz to 200 Hz, which is a frequency generated by hitting the keyboard in the bass range, is increased, and as a result, the localization becomes closer to that of a grand piano or the like.

[0013]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 and 2 show a first embodiment of an electronic keyboard musical instrument of the present invention, and in these figures, reference numeral 3
Reference numeral 1 denotes a main body case in which the keyboard 33 is arranged.

Both sides of the main body case 31 are supported by side plates 35, and a gable base 37 is arranged below the side plates 35. A pedal base 39 is horizontally bridged between the wife bases 37.

The body case 31 is a control panel 4
1, a top panel 43, and a back panel 45, which are arranged above the shelf plate 47. Arms 49 are arranged on both sides of the body case 31, and a keyboard lid 51 is slidably inserted into the control panel 41.

On the bass keyboard side and the treble keyboard side of the shelf board 47, a bass side speaker 53 and a treble side speaker 55 having substantially the same output characteristics are arranged. Then, the diaphragm 53 of the low-pitched speaker 53 and the high-pitched speaker 55.
a and 55a are through holes 47a and 4a formed in the shelf plate 47.
It is arranged to face 7b.

In this embodiment, a bass cabinet 57 for increasing the bass volume of the bass speaker 53 is arranged on the lower surface of the shelf 47 on the bass speaker 53 side. The bass cabinet 57 has a rectangular parallelepiped shape with an upper surface opened, and a through hole 47a of the shelf board 47 is opened in the upper opening.

The bass cabinet 57 is fixed to the lower surface of the shelf plate 47 via an L-shaped mounting member 59. Then, the bottom surface 5 of the bass cabinet 57
A duct 61 is opened in 7a, and a bass range cabinet 57 is a bass reflex type cabinet.

Therefore, the diaphragm 53 of the bass speaker 53
The sound wave from the front surface of a is inverted in phase by the duct 61, and is emitted downward from the duct 61. Moreover, the volume V of the bass cabinet 57 is set to the volume obtained from the equation described below.

V = [7 × 10 ⁴ a ⁴ / m ₀ f ₀ ² ] + V _P + V _sP [m ³ ] where m ₀ is the equivalent mass of the bass speaker 53, a is the effective vibration radius, and f ₀ is It is the lowest resonance frequency, V _P is the volume of the duct 61, and V _sP is the volume occupied by the bass speaker 53.

In this embodiment, the lowest resonance frequency f
₀ is a frequency around 50 Hz which is a frequency generated by hitting the keyboard 33 in the middle of the low tone range. In the electronic keyboard instrument described above, the bass side speaker 5 of the shelf board 47 is used.
Since the bass cabinet 57 is arranged on the lower surface on the 3 side, the bass speaker 5 is provided by the bass cabinet 57.
Since the volume of the bass range of 3 is increased, a localization close to that of a grand piano or the like can be obtained without deteriorating the treble characteristics of the speakers while using the bass side speaker 53 and the treble side speaker 55 having substantially the same output characteristics. be able to.

That is, in the above-described electronic keyboard instrument, since the volume of the bass speaker 53 is increased in the bass range by the bass cabinet 57, a localization close to that of a grand piano can be easily obtained.

Further, the bass-side speaker 53 having substantially the same output characteristics is provided for the bass keyboard side and the treble keyboard side speakers.
Since the high-pitched speaker 55 is used, a good stereo effect in the mid-high range can be obtained.

Furthermore, even when the bass speaker 53 and the treble speaker 55 having substantially the same output characteristics are used, it is not necessary to enlarge the diaphragms 53a and 55a of the speaker, so that the treble characteristics of the speaker are deteriorated. It is possible to surely avoid doing.

Further, the speaker system can be constructed by the relatively small bass speaker 53 and the treble speaker 55, so that the manufacturing cost can be reduced.

Further, in the above-mentioned electronic keyboard musical instrument, the volume is increased around the low frequency sound of 50 Hz which is an important frequency generated by striking the keyboard in the middle of the low frequency range or a frequency near this frequency, so that the grand piano is played. A closer localization can be obtained.

FIG. 3 shows a second embodiment of the present invention. In this embodiment, no duct is arranged on the bottom surface of the bass cabinet 63 and it is hermetically sealed to form a closed cabinet. Has been done.

In this embodiment, the bass range cabinet 6 is used.
The volume V of 3 is the volume obtained from the formula described below.
Has been. V = 3.5 × 10^Foura^Four/ m₀f₀ ²[(f_C/ F₀)²-1] [m³] Where m₀Is equivalent mass, a is effective vibration radius, f₀Is the lowest
Is the resonant frequency, f _CIs the bass speaker 53 in the bass range
Is the lowest resonance frequency when installed in the cabinet 63
It

Also in this embodiment, the lowest resonance frequency f ₀ is set to a frequency of about 50 Hz which is an important frequency generated by hitting the middle keyboard in the low tone range.

In this embodiment, the sound wave from the rear surface of the diaphragm 53a of the bass speaker 53 is radiated upward through the gap formed in the body case 31, but in this embodiment as well, the first embodiment is used. It is possible to obtain almost the same effect as.

In the above-mentioned embodiment, the lowest resonance frequency f ₀ is set to a frequency around 50 Hz which is a frequency generated by hitting a keyboard in the middle of the bass range, but the present invention is applicable. The frequency is not limited to the example, and may be set to a frequency of 50 Hz to 200 Hz, for example.

If the frequency is lower than 50 Hz, the size of the bass cabinet 57 becomes large, which is not practical. On the other hand, if the frequency exceeds 200 Hz, the effect obtained by the conventional structure is obtained. It becomes too close to obtain a sufficient effect.

Further, in the above-mentioned embodiment, the example in which the present invention is applied to the electronic piano has been described, but the present invention is not limited to such an embodiment and can be widely applied to electronic keyboard musical instruments such as electronic organs. Of course.

[0034]

As described above, in the electronic keyboard instrument according to the first aspect of the present invention, since the bass volume of the bass keyboard side speaker is increased by the bass cabinet, the bass keyboard having substantially the same output characteristics. It is possible to obtain a localization close to that of a grand piano, etc. without deteriorating the treble characteristics of the speaker while using the speakers on the side of the keyboard and the treble keyboard side.

In the electronic keyboard musical instrument according to the second aspect of the present invention, the frequency is 50 Hz to 2 which is a frequency generated by striking the keyboard in the low tone range.
Since the volume of the low-pitched sound of the frequency of 00 Hz is increased, there is an advantage that a localization closer to that of a grand piano or the like can be obtained.

[Brief description of drawings]

1 shows a first embodiment of an electronic keyboard instrument of the present invention, and is a cross-sectional view taken along the line I-I of FIG.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a sectional view showing a second embodiment of the electronic keyboard instrument of the present invention.

FIG. 4 shows an example of a conventional electronic keyboard instrument, and FIG.
FIG. 4 is a sectional view taken along line IV-IV of FIG.

5 is a cross-sectional view taken along the line VV of FIG.

[Explanation of symbols]

 31 main body case 33 keyboard 47 shelves 47a, 47b through holes 53 bass speaker (bass speaker) 53a diaphragm 55 treble speaker (treble keyboard speaker) 55a diaphragm 57, 63 bass cabinet

Claims (2)

[Claims] 1. Speakers having substantially the same output characteristics are respectively arranged on a bass keyboard side and a treble keyboard side of an upper surface of a shelf plate of a main body case in which a keyboard is arranged, and a diaphragm of the speaker is arranged on the shelf plate. In an electronic keyboard musical instrument arranged to face through-holes formed on the bass keyboard side and the treble keyboard side, on the lower surface of the shelf board, opened in the through-hole on the bass keyboard side of the shelf board, the bass keyboard side An electronic keyboard musical instrument characterized in that a bass cabinet for increasing the bass volume of a speaker is arranged. 2. The volume of the bass cabinet is 5
2. The electronic keyboard instrument according to claim 1, wherein the volume of low-pitched sound having a frequency of 0 Hz to 200 Hz is set to increase.