Patent Document

BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention generally relates to improvements in the structure and function of a musical instrument. The present invention more particularly relates to improvements in the structure and function of a harmonica.  
           [0003]    2. Background Information  
           [0004]    Harmonicas are among the world&#39;s oldest and most popular musical instruments. Harmonicas produce musical tones by a player blowing or drawing air into the harmonica to vibrate one or more of the reeds of the harmonica. One form of the harmonica is the ten-hole diatonic harmonica. In a diatonic harmonica, twenty reeds produce nineteen natural tones, with one tone being duplicated. The ten-hole diatonic harmonica typically has ten blow reeds, which sound in response to air blown into the harmonica by positive oral pressure; and ten draw reeds, which sound in response to air drawn in through the harmonica by negative oral pressure. The nineteen tones allow the player to play all the diatonic tones of a middle octave and most of the tones of a lower and a higher octave.  
           [0005]    A moderately advanced diatonic harmonica player can produce twelve additional tones by a process known as “bending,” whereby the player modifies the resonant volume in the vocal passage, principally with the tongue, to “bend” or adjust the tone produced to achieve the desired pitch. A “bend” is therefore a procedure involving the adjustment of the player&#39;s embouchure wherein a tone is flatted by causing the normally idle lower-pitched reed of the reed pair in a harmonica to vibrate in its opening mode.  
           [0006]    A more advanced player can also produce four additional tones by a technique known as “overblowing,” whereby the player more strictly matches the appropriate resonant volume with the tone he or she wishes to produce, typically causing the draw reed of the first, fourth, fifth, and sixth holes to produce tones corresponding to a flatted third of the low octave and a flatted third, fifth, and seventh respectively of the middle octave. Similarly, drawing and a strictly controlled shaping of the resonant passage will produce “overdraw” tones from the blow reeds corresponding to a sharped first, fifth and eighth of the highest octave. On an ordinary diatonic harmonica tuned to the key of C, the overblow tones are Eb-4 of the low octave, Eb-5, F#-5 and Bb-5 of the middle octave, and the overdraw tones are C#-6, G#-6 and C#-7 of the highest octave. Overblow and overdraw tones can be produced from all holes of the diatonic harmonica, but except for those listed, tones can be produced more easily with other techniques. See, e.g., U.S. Pat. No. 5,739,446 to Bahnson. Therefore, an overblow or overdraw procedure is one in which the tone is sharped by causing the higher pitched reed in a harmonica reed pair to vibrate in its opening mode. Overblow occurs on the first six holes of a standard diatonic harmonica wherein the higher-pitched reed is the draw reed; overdraw occurs on the last four holes of a standard diatonic harmonica wherein the higher-pitched reed is the blow reed.  
           [0007]    In all, the most skilled diatonic harmonica player can produce a total of thirty-eight tones from the ten-hole diatonic harmonica, using the normal playing, bending, overblowing, and overdrawing techniques. A problem with any musical instrument, including the diatonic harmonica, is that not all players are highly skilled or even moderately advanced at playing the instrument, and a majority of instrument players are at skill levels far below the advanced level and cannot significantly improve their skills even with much practice.  
           [0008]    The technique of “overblowing” is extremely difficult and diatonic harmonica players, even those of great skill, have been known to practice the technique for years before feeling comfortable enough to use the technique in a live performance. The same can be said of the “overdrawing” technique.  
           [0009]    Because the seven tones achieved by overblowing or overdrawing are not readily achieved on a ten-hole diatonic harmonica, many less-advanced players resort to a chromatic harmonica, which offers a full chromatic scale of semitones by means of a slide that directs air to reeds pitched a semitone higher than those activated without the slide. However, the chromatic harmonica is not as adaptable as the diatonic harmonica to musical expression such as the type of expression experienced in blues, country, soul, and jazz harmonica music. Although the chromatic scale is easier to play on the chromatic harmonica than on the diatonic, its more limited expression makes it less enjoyable for many, including both listeners and players.  
           [0010]    The construction of the diatonic harmonica (See, e.g., FIG. 1) includes a set of ten flexible metallic reeds affixed to a flat reed plate containing rectangular slots through which the reeds vibrate. The typical construction provides an individual reed for each slot. Two such sets of reed plates are typically attached to opposing faces of a comb, thereby creating ten cells, each allowing two notes to be played per cell of the comb: one when blowing and one when drawing.  
           [0011]    There are, however, limitations associated with this construction. The usual mechanical connection of reeds on a top surface of the reed plate can create a gap at the reed tip and along the lateral sides or flanks of the reed through which air may leak during play. When the reed vibrates due to a physical influence such as the blowing or drawing action of a musician, these gaps can widen and narrow to permit the reed to vibrate. However, when vibration is initiated, these gaps can also result in one or more unsatisfactory air leaks that can cause the player to blow more forcefully, alter his embouchure, and possibly stop reed vibration from occurring.  
           [0012]    This problem is especially acute when attempting to play notes arising from a “bent,” “overblown” and/or “overdrawn” procedure. These notes are characterized by an anomalous physical behavior of two given reeds positioned in a cell of the harmonica. As shown in Bahnson et al., “Acoustic and Physical Dynamics of the Diatonic Harmonica,”  Journal of the Acoustical Society of America . Vol. 103(4), pp. 1234, 1244, 1998, when one of these maneuvers is performed and achieved, the normally stationary reed can be caused to vibrate while the normally active reed is caused to close. In the case of the overblow procedure, for example, the draw reed operates in an “opening” fashion while the blow reed operates in a “closing” fashion.  
           [0013]    As previously discussed, the gap formed between the blow reed and its corresponding slot can create an air leak during this procedure. Consequently, there may be insufficient air pressure to induce vibration in the opening reed. Furthermore, the acoustic impedance of the oral-reed system may be affected so as to prevent vibration, or cause dissonant vibration within the harmonica.  
           [0014]    An additional problem associated with conventional harmonica play is the occurrence of aberrant and discordant whistling or squeaking sounds while attempting to play a note. These aberrant sounds can be particularly problematic while attempting an overblow or overdraw procedure. The cause of this phenomenon is the establishment of “edge tones” created by the flow of air through a gap or gaps formed between one or more reeds and the reed plate and subsequent torsional vibration of the reed.  
           [0015]    Another problem associated with conventional harmonicas is the difficulty in aligning the reeds within the reed slots of the reed plate during assembly. The clearance between the lateral edges or flanks of the reeds and the corresponding edges of the slot is typically small, in the approximate range of less than 0.002″. Because the reed is often affixed to the reed plate with a single rivet or other similar mechanical fastener, it is possible for the reed to rotate about the rivet thereby causing a nonparallel alignment between the rotated reed and the reed plate. Furthermore, irregularities or burrs introduced during fabrication of the reed or reed plate can adversely affect the free vibration of the reed. This is exacerbated when the reed is not properly aligned in its slot within the harmonica.  
           [0016]    An additional problem associated with conventional harmonica construction is that roughened surfaces can be present on the edges and other internal surfaces of a reed slot. Because these slots are typically fabricated by the shearing action of a die, their internal surfaces are typically characterized by burrs, grooves and other irregular projections and recesses. These irregularities introduce non-uniformity into the reed slot of the harmonica and can interrupt the smooth flow of air through the reed passage.  
           [0017]    A further problem with conventional harmonicas is that the material properties of the reed usually alter during the life cycle of the instrument thereby affecting the pitch and alignment of the reed. If the instrument is played with greater than usual force or air pressure, for example, the pitch of the reed can be altered. To rectify the pitch, the instrument must be disassembled to adjust the reeds. To lower the pitch of the reed, material is removed from the root of the reed, usually by abrasive means, such as sandpaper. To raise the pitch of the reed, material is removed from the reed tip. To readjust the reed position, the reed is manually or mechanically deflected in a exaggerated fashion in the direction opposite of the dislocation, perhaps resulting in a weakening of the attachment of the reed to the reed plate.  
           [0018]    A still further problem associated with conventional harmonica play is that the player must modify his or her oral cavity to achieve certain bends, overblows, or overdraws. Low draw bends typically require excessively large embouchure, necessitating that the jaw be lowered, and the tongue positioned low in the oral cavity. Conversely, overblows, blow bends, and overdraws require relatively small oral volume and that the tongue of the musician to be positioned against the palate with the tip forward against the upper teeth. The volume provided within the comb of the harmonica supplements the volume required within the oral cavity of the musician. Therefore, enlarging the cavity would facilitate draw bends, while reducing the volume of the cavity would facilitate overblows, overdraws and blow bends.  
           [0019]    A number of devices have been used to improve the playing of harmonicas. Paris, U.S. Pat. No. 574,625, discloses a siding mouthpiece for transferring a blast of air from one cell chamber to another without moving the lips. Newman, U.S. Pat. No. 1,671,309, discloses a chromatic harmonica having a frontal slide which occludes certain blow holes in the harmonica to allow the player to achieve a chromatic scale, as opposed to a diatonic scale. Other chromatic harmonicas having blow hole-occluding devices include U.S. Pat. Nos. 1,752,988; 2,005,443; 2,339,790; and 2,675,727.  
           [0020]    Bahnson, U.S. Pat No. 5,739,446, discloses a harmonica and method of playing which involves the use of a valve mechanism. A sliding set of louvers is added to one side of each reed plate, which apparently, when activated, block the air leakage from the inactive reed. This mechanism appears to be relatively complicated and expensive to implement. The Bahnson harmonica also appears to require the player to activate the valve at the exact instant that the overblow note is to be played, thus requiring additional motions and interaction with the harmonica by the player, and preventing modulation of frequency as required for certain tremelo effects.  
           [0021]    Accordingly, an advance in the art could be realized if a harmonica could be constructed which readily permits the production of bent, overblown, and overdrawn tones, enabling even the player having limited skills to achieve the characteristic expression of the diatonic harmonica and yet realize the full half tone scale capability of the chromatic harmonica. It would also be beneficial to provide a harmonica that permits the overdrawing and overblowing techniques of the invention to be practiced without otherwise requiring any significant changes in playing techniques. Another is significant benefit could be realized from a harmonica that is more susceptible to the techniques of bending, overblowing and/or overdrawing.  
           [0022]    A harmonica with reeds and associated reed plates that reduce the excessive leakage of airflow from the cells of the harmonica is also needed. What is also needed is a simple construction for use in fabricating and assembling reed plates that also improves harmonica performance and reduces lifetime maintenance and tuning. Another advantage could be realized by providing a harmonica having reed slots with generally uniform and relatively smooth surfaces that improve interaction between reeds and reed slots. What are also needed are improvements in the structure of the comb body, the reed plates and the position of reeds within a conventional harmonica. A harmonica is needed that can achieve draw and blow bends by improving interaction between a reed pair in a cell.  
           [0023]    Still another problem that needs to be addressed is that of achieving sufficient loudness from the harmonica. An improvement is needed that can increase the amount of time the reed spends in the slot, thereby increasing the time that the reed receives aerodynamic impetus for vibration. Under circumstances of high-pressure airflow in the harmonica, such as when the player exerts sufficient pressure to cause the tip of reed to vibrate entirely through its respective slot, then a new leakage path is created. A means of reducing the leakage caused by this new path would be advantageous in an improved harmonica.  
         SUMMARY OF THE INVENTION  
         [0024]    The improved harmonica structures of the present invention have met and/or exceeded the above-described needs.  
           [0025]    The harmonica structures of the present invention include, in one embodiment, a reed comb having a common bridge with reeds formed integrally with the common bridge. The reed plate has a plurality of reed slots formed therein and is adapted to receive the reeds of the reed comb into corresponding slots formed in the reed plate. The reed plate has a first portion positioned within a first plane and a second portion positioned in a second plane. The second portion of the reed plate has a stepped portion formed therein adapted to receive a reed of the reed comb therein to permit substantial encasement of the reed within the reed slot.  
           [0026]    In the harmonica of the present invention, one or more counterbores can be formed in the reed plate adjacent to the tips of the reeds. The counterbore can extend a distance beyond or behind the reed tip and can be provided in a variety of configurations, such as a rectangular shape. In addition, material can be applied to a surface of the reed plate at a location adjacent to the flanks of the reeds to resist leakage of air between the reed plate and the flanks of the reed during harmonica play. The reed plate can include a first stepped portion upon which the roots of the reeds are positioned and a second stepped portion positioned adjacent to the tips of the reeds.  
           [0027]    In another aspect of the present invention, the reeds can be formed by direct cutting or forming of the reeds in the reed plate. A reed is formed by cutting along three sides of its perimeter and leaving the fourth or “short” side uncut. This provides a substantially integrally formed reed plate.  
           [0028]    In still other aspects of the present invention, a radiused surface can be formed on a portion of the reed or on the surface of the reed slot in which the reed is positioned. A substantially wedge-shaped comb having angled top and bottom surfaces can also be provided. In another aspect of the present invention the height of the comb and the thickness and structure of the reed plates can be adjusted to achieve a variety of acoustical objectives. The width of the cells in the comb can also be adjusted to vary the volume of individual cells. In addition, substantial axial alignment of the roots of a given pair of reeds can be made to provide different acoustical results for the harmonica. The walls of the cells in the comb can also be tapered to alter acoustical effects. A flexible structural member can be used in conjunction with the inside surface of the cells of the comb to close a slot in the reed plate during harmonica play.  
           [0029]    The present invention will be more fully understood from the following description of the invention and by reference to the figures and claims appended hereto. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0030]    A full understanding of the invention can be gained from the following detailed description of the invention when read in conjunction with the accompanying drawings in which:  
         [0031]    [0031]FIG. 1 is an exploded, isometric view of a conventional diatonic harmonica;  
         [0032]    [0032]FIG. 2 is a sectional view of a set of reeds in a conventional diatonic harmonica;  
         [0033]    [0033]FIG. 3 is a plan view of a reed attached to a reed plate in a conventional harmonica;  
         [0034]    [0034]FIG. 4 is a sectional view of a single reed attached to a reed plate in a conventional harmonica;  
         [0035]    [0035]FIG. 5 is a sectional view taken along  5 - 5  of FIG. 3;  
         [0036]    [0036]FIG. 6 is a partially schematic sectional view of a reed and reed plate exhibiting air leakage during a closing action of the reed;  
         [0037]    [0037]FIG. 7 is a partially schematic sectional view of a reed and reed plate exhibiting air leakage during an opening action of the reed;  
         [0038]    [0038]FIG. 8 is a top plan view of a reed plate of an embodiment of the present invention;  
         [0039]    [0039]FIG. 9 is a sectional view taken along  9 - 9  of FIG. 8;  
         [0040]    [0040]FIG. 10 is a sectional view taken along  10 - 10  of FIG. 8;  
         [0041]    [0041]FIG. 11 is a sectional view taken along  11 - 11  of FIG. 8;  
         [0042]    [0042]FIG. 12 is an exploded isometric view of a reed comb and reed plate of an embodiment of the present invention;  
         [0043]    [0043]FIG. 13A is a fragmentary, isometric view of an embodiment of the present invention;  
         [0044]    [0044]FIG. 13B is a fragmentary, isometric view of an embodiment of the present invention;  
         [0045]    [0045]FIG. 13C is a fragmentary, isometric view of an embodiment of the present invention;  
         [0046]    [0046]FIG. 14 is an exploded isometric view of a reed comb and reed plate of an embodiment of the present invention;  
         [0047]    [0047]FIG. 15 is an isometric view of an integrated reed-bridge reed plate of the present invention;  
         [0048]    FIGS.  16 - 19  are top plan views of reed plate embodiments of the present invention;  
         [0049]    [0049]FIGS. 20 and 21 are plots of the real component of acoustical admittance versus frequency during harmonica play;  
         [0050]    [0050]FIG. 22 is a sectional view of a portion of a reed plate and reed embodiment of the present invention;  
         [0051]    [0051]FIG. 23 is a sectional view of a comb embodiment of the present invention;  
         [0052]    [0052]FIGS. 24 and 25 are sectional views of comb and reed plate embodiments of the present invention;  
         [0053]    [0053]FIG. 26 is a partially schematic top plan view of a conventional reed plate;  
         [0054]    [0054]FIG. 27 is a partially schematic top plan view of a reed plate embodiment of the present invention;  
         [0055]    [0055]FIG. 28 is a sectional view of a reed embodiment of the present invention;  
         [0056]    [0056]FIG. 29 is a sectional view of a reed plate embodiment of the present invention;  
         [0057]    [0057]FIG. 30 is an enlarged sectional view taken at  30 - 30  of FIG. 29;  
         [0058]    and,  
         [0059]    [0059]FIG. 31 is a sectional view of a flexible member embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS  
       [0060]    Referring now to FIGS. 1 and 2, a diatonic harmonica  2  is shown including a body or “comb” depicted generally at  10 . The comb  10  is preferably fabricated of a wood, resinous plastic or metal material. The comb  10  is sandwiched between two reed plates  11 ,  12  which include a blow reed plate shown generally at  11 -and a draw reed plate shown generally at  12 . The plates  11 ,  12  are further sandwiched within a housing comprising an upper cover  13  and a mating cover  14 . The plates  11 ,  12  are preferably composed of brass or another similar material suitable for use in a harmonica. It can be appreciated that the harmonica  2  can be assembled by use of conventional mechanical fasteners such as screws, bolts and the like.  
         [0061]    As shown in FIGS. 1 and 2, the blow reed plate  11  contains a plurality of blow reed slots  30 - 39 , that each accommodate a blow reed such as reed  15  (shown slightly flexed) in each blow reed slot, such as slot  30 . The blow reeds  15  are mounted on the blow reed plate  11  such that when the blow reed plate  11  is positioned next to the comb  10  during assembly, the blow reeds  15  seat inside the cells such as cell  17  formed within the comb  10 . These cells  17  allow air passage into and out of the harmonica  2  by the actions of blowing and drawing, respectively.  
         [0062]    Referring again to FIGS. 1 and 2, the draw reed plate  12  has within it a series of draw reed slots,  40 - 49 , each including a draw reed such as draw reed  20  therein. The draw reeds  20  are mounted on the outside of the draw reed plate  12  relative to the comb  10 . The draw reeds  20  naturally vibrate when the harmonica player draws air out of the harmonica. Each blow reed  15 , such as the blow reed  15  in position  30 , has a corresponding draw reed  20 , such as the draw reed  20  in position  40 , positioned substantially opposite the blow reed  15 , such that the matched pair of reeds  15 ,  20  share a common cell  17 . During harmonica play, each cell  17  communicates with a blow reed  15  and a draw reed  20  as a matched pair of reeds  15 ,  20 .  
         [0063]    Referring again to FIGS. 1 and 2, the draw reeds  20  in positions  40 - 49  normally sound only when air is drawn out of the harmonica  2 . This is how the diatonic harmonica  2  is designed to operate during normal play. However, it has been established that during certain procedures, known as “bends,” “overblows,” and “overdraws,” wherein the resonance of the vocal tract is critically altered, both the draw reeds  20  and the blow reeds  15  can be caused to vibrate sympathetically.  
         [0064]    Referring again to FIGS. 1 and 2, reeds  15  and  20  are normally attached by a rivet or another suitable mechanical fastener to the reed plates  11 ,  12  so that each reed, in its detent or resting position, is in a substantially parallel position with respect to the reed plate but is also substantially outside respective reed slots,  30  and  40 . In normal functioning of the harmonica  2 , the reeds are caused to vibrate by positive or negative air pressure applied to the cells  17  by the player. During a blowing action, the blow reed  15  is caused to close while draw reed  20  is caused to open. The closing action of the blow reed  15  normally results in a sustained oscillation due to the inverse relationship between the air pressure and the aerodynamic resistance across the reed slot  30 . That is, additional instantaneous air pressure causes the reed  15  to close further, thereby decreasing the clearance between the reed  15  and the blow reed plate  11 , and thereby increasing the aerodynamic drag. This, in turn, causes a reduction of airflow that inevitably allows the normal elasticity of the reed  15  to reopen the slot  30 . By contrast, the draw reed  20  is moved to an open position during a blowing operation, thereby decreasing its aerodynamic resistance. As such, the draw reed  20  does not support oscillation, but instead accounts for unwanted loss of air pressure. Likewise, when the player draws through passage  17 , the roles of the reeds are reversed.  
         [0065]    Under certain situations, both reeds can be caused to oscillate. This generally occurs when the player is drawing through the first six cells  21 - 26  of the harmonica  2  or blowing through the last four cells  27 - 30  of the harmonica. In each of these situations, the opening reed is tuned to a frequency lower than the closing reed in the shared, corresponding cell, such as cell  17  for the reeds  15 ,  20 . Likewise, during a draw bend or blow bend procedure, the vibration of the lower-pitched opening reed increases while the vibration of the closing reed decreases.  
         [0066]    Referring now to FIGS. 3 through 5, a reed plate  52  is shown having a reed  54  attached thereto such as by a mechanical fastener or rivet  56 . In a closed position  55  of the reed  54  as it vibrates in position over the slot  58  formed in the reed plate  52 , lateral gaps  60 ,  62  are formed between the reed  54  and the reed plate  52 . During harmonica play, these gaps  60 ,  62  disadvantageously permit air to escape or enter the slot  58  between the reed  54  and the reed plate  52 .  
         [0067]    As shown more particularly in FIGS. 6 and 7, during harmonica play air flow can pass through lateral gaps  60 ,  62  during a closing action or by relative motion of the reed  54  in the direction of the slot  58  of the reed plate  52  (as shown in FIG. 6). The closing action of the reed  54  is caused by the negative air pressure −AP. In addition, the air flow can pass through lateral gaps  60 ,  62  during an opening action or by relative movement of the reed  54  away from the reed plate  52  and the slot  58  (as shown in FIG. 7). The opening action of the reed  54  is caused by the positive air pressure+AP.  
         [0068]    Referring now to FIGS. 8 through 12, the harmonica of the present invention includes a reed comb  72  having a plurality of integrally formed reeds such as reeds  74 , 76 , 78  extending from a common bridge  80 . The reed comb  72  is adapted to be received and connected by mechanical attachment such as by rivet  82  onto a reed plate  84  having a plurality of reed slots such as reed slot  79  formed therein. The reed plate  84  has a first portion  86  positioned within a first plane  88  and a second portion  90  extending through a second plane  92 . The first plane  88  is substantially parallel to the second plane  92  as shown. The second portion  90  of the reed plate  84  also has a stepped portion  91  on a surface of the first portion  86  of the reed plate  84 . The root  77  of the reed  76  rests on this stepped portion  91  and is mechanically connected as previously discussed to the reed plate  84  by the rivet  82 . A counterbore  96  is formed within the second portion  90  of the reed plate  84 . It is therefore the function of the stepped portion  91  to permit substantial encasement of the reed  76  within the reed slot  79 . The counterbores  96 ,  98  can extend distances  100 ,  102 , respectively beyond the tips  104 ,  106  of the reeds  76 ,  74 .  
         [0069]    It can be appreciated that the reed plates and reed combs can be fabricated in any of several ways including conventional milling, die stamping, electron discharge machining, laser cutting, electroforming or photo-etching to promote reed dimensions and alignment relative to the common bridge. Furthermore, an integrally formed and single-piece reed comb is relatively easier to assemble to the reed plate than a conventional harmonica design typically wherein ten individual reeds are assembled to a reed plate. In addition, in the harmonica of the present invention, the rotational alignment of the reed with respect to the reed comb is assured by the integral association of the reeds with the common bridge of the reed comb.  
         [0070]    This invention therefore features a novel configuration of reeds within the reed slots of a given reed plate. Unlike the stacked arrangement of reeds on top of a conventional reed plate slot, the reeds of this invention are situated partially or substantially within a counterbore. The counterbore proves a small clearance at the tip of the reed near the second portion of the reed plate. However the flanks of the reed are positioned substantially within the slot of the reed plate when the reed moves toward the reed plate slot during play. This structure thereby substantially interrupts the leakage of air characterized by conventional harmonica play. This interruption of airflow also reduces the edge tones responsible for undesirable whistling and squealing while playing a harmonica.  
         [0071]    The reeds of the present invention are composed of a material selected from the group of elastic metals including phosphor bronze, beryllium copper, brass, and nickel-titanium alloy. Nickel-titanium alloy is characterized by relatively high elasticity and durability, and is therefore a preferred material for the reeds of the present invention. This alloy also addresses the problems associated with relatively softer materials, namely the problem of detuning of the harmonica due to strain hardening and fatigue.  
         [0072]    In addition, a material that is too yielding can result in dislocation of harmonica components such as the reeds.  
         [0073]    It should be appreciated that although the embodiment of the present invention depicted in FIGS. 8 through 12 shows a reed plate having material removed near the tip and near the base of the reed, substantially similar properties can be achieved if material is added along the flanks of the reeds. Referring now to FIGS. 13A, 13B and  13 C, it is shown that material can be removed from the area adjacent to the root  107  of the reed  108 . Material can also be removed from the reed plate in the vicinity of the tip  109  of the reed  108 . As shown in FIG. 13B, material  110  can be positioned adjacent to the reed  108  to resist leakage of air between the reed plate and the flanks of the reed  108  during harmonica play. Material removed from the vicinity of the tip  109  of the reed  108  can form a substantially ramped surface, as shown in FIG. 13C.  
         [0074]    Referring now to FIG. 14, the reed plate  112  of the present invention can include two stepped portions  114 ,  116  in conjunction with assembly of a reed comb  118  with the reed plate  112 . The stepped portion  116  extends along substantially the entire length of the reed plate  112 . In the form of the invention shown, a plurality of recesses such as recesses  120 ,  122 ,  124  are also formed in the reed plate  112 .  
         [0075]    Referring now to FIG. 15, in another embodiment of the present invention, the reeds  125 ,  126 ,  127  are formed integrally with the reed plate  128  of the harmonica by cutting along three sides  129 ,  130 ,  131  of the perimeter of each reed. This permits each reed to cantilever from the fourth, uncut side  132  of each reed when the reed vibrates during harmonica play.  
         [0076]    Referring now to FIGS. 16 through 19, FIG. 16 shows an aspect of the present invention wherein the recess  142  at the tip  144  of the reed  146  positioned in the slot  148  of the reed plate  150  is a substantially circular counterbore. FIG. 17 shows an aspect wherein the recess  152  at the tip  154  of the reed  156  is a rectangular counterbore located primarily forward of the tip  154  of the reed  156  on the reed plate  150 . FIG. 18 shows an aspect wherein the recess  162  at the tip  164  of the reed  166  is a rectangular counterbore located primarily behind the tip  164  of the reed  166  on the reed plate  150 . FIG. 19 shows an aspect wherein the recess  172  at the tip  174  of the reed  176  is a rectangular counterbore located both in front of the tip  174  of the reed  176  a distance L 1  and behind the tip  174  of the reed  176  a distance L 2 .  
         [0077]    Referring now to FIGS. 20 and 21, the acoustic performance of reeds in a harmonica can be characterized by their acoustic admittance, defined as the first derivative of acoustic flow with respect to pressure. This is typically a complex quantity, containing a real part and an imaginary part. Vibration theory prescribes that when the real part of the complex admittance is negative, the reed exhibits sustained vibration. When plotted as a function of frequency and pressure, the typical response of a pair of reeds such as those found in a harmonica is shown as a solid-line plotted in FIGS. 20 and 21.  
         [0078]    [0078]FIG. 20 depicts the admittance of a reed pair wherein the higher-pitched reed is operating as a closing reed and the lower-pitched reed is operating in its opening mode. For example, this admittance is provided when a harmonica player is drawing holes  1  to  6  or blowing holes  7  to  10  of a standard 10-hole diatonic harmonica. The fundamental frequencies of the lower-pitched reed and the higher-pitched reed are shown as f LP  and f HP , respectively.  
         [0079]    [0079]FIG. 21 depicts the admittance of a reed pair wherein the lower-pitched reed is operating as a closing reed and the higher-pitched reed is operating in its opening mode. This admittance characteristic is provided when the player is blowing through holes  1  to  6  or drawing through holes  7  to  10  of the 10-hole diatonic harmonica. The second “dip” seen in FIG. 20 corresponds to the overblow or overdraw note which is distinct from the respective blow and draw notes.  
         [0080]    In the context of FIGS. 20 and 21, an object of the present invention is to increase the range (bandwidth) of the unstable frequencies and to increase the range of acoustic admittance for which the reed is unstable. This, in turn, enlarges the range of oral geometries that a player may achieve a desired tone. It can also have the effect of lowering the pressure at which instability occurs. This is shown more particularly by the dashed curves in FIGS. 20 and 21. These acoustic admittance curves of reed pairs are adapted and shown herein for illustrative purposes from Johnston, R. B., “Pitch Control in Harmonica Playing,”  Acoust. Aust.  15(3), 69-75 (1987).  
         [0081]    Referring now to FIG. 22, in another embodiment of the present invention, a cross-section of a reed  202  of the present invention is shown partially positioned within its respective reed slot  204  in a reed plate  205 . The radii  206 ,  208 ,  210 ,  212 ,  214 ,  216  are provided along the reed  202  and the upper and lower portions of the flanks  218 ,  220  of the reed  202  to improve the aerodynamics of the airflow traveling between the reed  202  and the reed plate  205  during harmonica play. These radii are preferably in the range of about 0.001 to 0.0025 inches. An advantage of these radii is reducing undesirable edge tones usually causing discordant “whistle” sounds emanating from the closing action of the reed  202 .  
         [0082]    Referring now to FIG. 23, in another aspect of the present invention, the comb  232  of the harmonica is principally a wedge-shaped structure having a top surface  234  sloped at an angle a with respect to vertical and a bottom surface  236  angled at an angle β with respect to vertical. This aspect of the present invention alters the acoustic properties of the air space  238  within the comb  232  and thereby affects the timbre of the sound produced. The angles α and β can each be in the range of approximately 75 to 105 degrees.  
         [0083]    Referring now to FIG. 24, in another aspect of the present invention, the comb  252  of the harmonica can be reduced to a height h 1 . The advantages of this configuration are twofold. First, the relatively close distance d 1  of the reeds  254 ,  256  in the cell  258  improves their interaction during harmonica play. Accordingly, blow bends and draw bends are more readily performed by the harmonica player. This feature is particularly desirable on the first four and last four holes of a conventional ten-hole diatonic harmonica. Second, the volume of the cavity  258 , being reduced from a typical volume, resists the player from reducing his/her mouth cavity to such a considerable degree than is conventionally needed for blow bending, overblowing, and overdrawing procedures. This feature is most desirably utilized on the last four holes of a conventional ten-hole diatonic harmonica. The height h 1  is preferably in the range of 3.5 to 4.5 mm or most preferably about 4.0 mm as compared to the typical height dimension of about 6.2 mm. In order to maintain a normal opening at the lips of the player, outward flares  260 ,  262  are provided, respectively, at the front edge of the reed plates  264 ,  266 .  
         [0084]    Referring now to FIG. 25, another aspect of the present invention is shown wherein the comb  272  is increased to a height h 2 . The advantages of this configuration are twofold. First, the increased distance d 2  between the two reeds  274 ,  276  in the cell  278  reduces their interaction. Accordingly, dissonant overblows and overdraws can be avoided. This feature is most desirable on the last seven holes of a ten-hole diatonic harmonica. Second, the volume of the cavity  278 , being increased from its normal volume, resists the player from increasing his/her mouth cavity to a point greater than currently required for a draw bending procedure. This feature is most desirable on the first four holes of a diatonic harmonica. The height h 2  is preferably in the range of about 7.0 to 8.5 mm or most preferably 8.0 mm as compared to the typical height dimension of about 6.2 mm. To maintain a normal opening for the lips of the player (not shown), inward flares  280 ,  282  are provided, respectively, at the front edge of the reed plates  284 ,  286 .  
         [0085]    Referring now to FIG. 26, a conventional comb  312  is shown having all cells of substantially the same width or approximately 4.2 mm. Referring next to FIG. 27, in accordance with an aspect of the present invention, the volume of each of the lower three cells  334 ,  335 ,  336  is increased and the volume of the upper two cells  342 ,  343  is decreased by comparable enlargement or reduction of the widths of these cells. The range for the width of these cells with reduced or enlarged widths is preferably from about 3 mm to 6 mm.  
         [0086]    Referring now to FIG. 28, in another aspect of the present invention, the reeds  362 ,  364  of the harmonica can be mounted on their respective reed plates  368 ,  370 ) so that their respective roots  369 ,  371  are positioned in a substantially axial alignment with respect to each other. This provides the benefit of increasing the interaction between the reeds, thereby providing the improved play benefits previously described for other aspects of the present invention.  
         [0087]    Referring now to FIGS. 29 and 30, in another aspect of the present invention, the thickness t of the reed plate  382  can be in the range from about 1.5 to 2 mm. In contrast, a conventional harmonica has reed plates with thicknesses typically in the range of about 0.9 to 1.0 mm. This provides the advantage of increasing the amount of time the reed  386  spends within the slot  387 , and thereby avoids leakage that occurs when the tip  388  of the reed  386  passes completely through the slot  387 . FIG. 30 presents an enlarged view of section  30 - 30  of FIG. 29 that shows the detail of the reed plate  384  near the tip  392  of the reed  390 . An additional feature of this reed plate  384  is a taper angle θ, corresponding to the arc of the reed  390  during its flexion. The inclusion of this taper angle θ also serves to reduce the leakage created by a gap  394  formed between the tip  392  of the reed  390  and the internal surface  396  of the reed slot  391 , which gap  394  widens as the reed  390  flexes into the reed slot  391 . The taper angle θ is typically in the range of approximately one to seven degrees.  
         [0088]    Referring now to FIG. 31, in another aspect of the present invention, a flexible member  402  is affixed at one end of the flexible member  402  to a surface  403  of the reed plate  404 . The length and width of this member  402  are each slightly larger than the reed slot. Therefore, when air pressure is provided that causes the reed  406  to open, this normally resiliently biased member  402  is forced against the reed slot thereby substantially closing off air leakage. When air pressure is applied causing this reed  406  to close, the flexible member  402  is deflected from the source of air pressure, thereby not substantially affecting the function of the associated reed  406 . This feature is beneficial for the draw reeds of the first three holes of a conventional diatonic harmonica, wherein excessive loss of air pressure is experienced when the player attempts to play a blow note, and also wherein overblows are not performed, thus the draw reed is not required to operate in the opening fashion. In the preferred embodiment, the flexible member is made from about 0.004″ thick polyethylene, but any suitable material of equivalent thickness and stiffness may be used.  
         [0089]    It can be appreciated that the improvements described herein need not be applied to all 20 reeds, but could be applied to only one reed, or some other reasonable combination of reeds of a harmonica.  
         [0090]    Whereas certain terms of relative orientation such as “upper” and “lower” have been used herein to describe the invention, these terms are intended for purposes of illustration only and are not intended to limit the scope of the present invention. In addition, while specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the appended claims and any and all equivalents thereof.

Technology Category: 3