Abstract:
A microphone mounting system for an acoustic, stringed instrument that places the microphone in sufficient proximity to the instrument sound hole to capture the warmth and tone of the instrument while assisting in feedback control, and without altering or damaging the finish or structure of the instrument. The system includes a grip, such as a corrugated plastic tube, attached to a microphone and wedged into the instrument sound bole to be held in place through frictional engagement. The microphone is connected to an instrument cable coupler, clamped to the side of the instrument, which is then connected to a sound amplification system.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority from provisional patent application No. 60/911,255 filed on Apr. 11, 2007. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to devices for mounting microphones in proximity to acoustic instruments, and, more particularly, to a system for temporarily mounting a microphone in close proximity to the sound hole of an acoustic instrument by providing an attachment element that engages the sides of sound hole and avoids alteration and/or damage to the body of the instrument. 
     2. Description of the Related Art 
     There have been numerous attempts to electrically amplify acoustic violins and other acoustic instruments with an F-style sound hole. These attempts have all suffered from significant disadvantages, typically through compromising the quality of the sound produced by the instrument, or the structure of the instrument, or both. Current solutions for acoustic amplification typically cause acoustic instruments to sound artificial and distorted. 
     Previous attempts to amplify acoustic stringed instruments have included the installation of electric pickup and piezoelectric amplification systems that alter the instrument&#39;s tone and render the instrument unplayable without amplification, i.e. render the instrument no longer suitable for unamplified acoustic sound production. Additionally, these methods and associated devices are often expensive, often permanently alter or damage the instrument, and achieve less than desirable resulting sound quality. Attempts to provide amplification by simply attaching microphones to the body of the instrument have also proven bulky and ineffective for use with hand-held instruments, particularly violins, that may involve significant body movement when playing. Devices that mount a microphone inside an acoustic instrument typically provide poor feedback control and offer limited adjustability to the instrument player. In addition, such devices typically require some incursion and damage to the structure of the instrument to effect installation. Prior art devices also typically do not provide sufficient cable support and stability. 
     Cable couplers are used for joining sequential cables that convey an output signal from an instrument to an external power amplifier. The coupler comprises a cylindrical body having a hollow sleeve at each end that form opposing receptacles. One receptacle is sized to receive a plug at the end of an instrument cable leading to an amplifier, and the other receptacle is sized to receive a plug at the end of a cable leading from a microphone or other source of an electrical sound signal. The two plugs may be the same or different sizes and, therefore, the receptacles at either end of the coupler may have the same or different dimensions. 
     A bracket for clamping a violin chin rest to the body of a violin typically comprises a lower clamping member for engaging the back surface of the base of a violin body and an upper clamping member for engaging the front surface of the base. The upper and lower clamping members are joined to one another by a pair of upright members disposed parallel to one another and perpendicular to the upper surface of the lower clamping member. The upright members have means for varying their length, such as turnbuckles, so that the upper and lower clamping members may be drawn together and against the adjacent surfaces of the violin, thereby holding the chin rest in a fixed position upon the violin. 
     Examples of amplification devices in the prior are shown in the disclosure of the following U.S. Pat. No. 7,138,577 (Takabayasi); U.S. Pat. No. 7,084,341 (Barr); U.S. Pat. No. 7,015,390 (Rogers); U.S. Pat. NO. 6,681,661 (Lalonde); U.S. Pat. No. 6,515,214 (Takabayasi); U.S. Pat. No. 6,441,293 (LaBarbera); U.S. Pat. No. 6,018,120 (Steinberger); U.S. Pat. No. 5,194,686 (Winkler); U.S. Pat. No. 5,010,803 (Donnell); U.S. Pat. No. 4,995,293 (Anderson); U.S. Pat. No. 4,843,937 (Murphy); U.S. Pat. No. 4,748,886 (De Byl): U.S. Pat. No. 4,495,641 (Vemio); and U.S. Pat. No. 4,404,885 (Salak). Examples of electrical cable couplers are well known in the art. Two particular examples are shown in the disclosure of the following U.S. Pat. No. 4,082,409 (Bailey et al.) and U.S. Pat. No. 4,519,287 (Naruse). Examples of brackets for clamping a chin rest to a violin are shown in the disclosure of U.S. Pat. No. 904,258 (Henrikson et al.) and U.S. Pat. No. 4,534,259 (Wolf). 
     It is clear that there exists a need for a device that can mount a small, high sound quality microphone directly over an instrument F-style, or similar, sound hole for optimal acoustic sound reproduction, while remaining easily removable and causing no damage or alteration to the structure or finish of the instrument. 
     BRIEF SUMMARY OF THE INVENTION 
     An embodiment of the invention includes a generally cylindrical deformable grip for mounting a microphone proximate a longitudinally elongated and transversely narrow acoustic instrument sound hole. The sound hole is defined by at least two opposing, elongated walls that are typically aligned generally parallel to one another near the central portion of the hole and then taper toward each other near the longitudinally opposed sound hole ends. 
     The grip comprises a deformable material such as a hollow, generally cylindrical tube made of resilient plastic or a generally cylindrical length of sponge or loam rubber. The lower end of the grip is free to fit inside the sound hole and should be sized so that the diameter of the grip, when measured across a section of the grip transverse to its longitudinal axis, exceeds the width of the portion of the sound hole selected for holding the grip The grip may then be squeezed between the user&#39;s thumb and forefinger to fit inside the sound hole, and then released to expand and exert an outwardly biased force against the adjoining sides of the sound hole. 
     The upper end of the grip is held within the jaws of a small clip connected to a microphone. Examples in the prior art of microphones provided with clips include various lavaliere-type transducer or condenser microphones having clips for attaching the microphones to the wearer&#39;s clothing. The microphone clip may be positioned in engagement with the grip so that the clip holds the microphone facing the sound hole, with the sound-receiving structures of the microphone pointed toward, or even slightly within, the proximate portion of the sound hole. 
     The microphone cable plugs into an electrical cable coupling or coupler that is secured to the side of an instrument (such as a violin) using a coupler mounting bracket. Upper and lower jaws of the coupler mounting bracket are drawn together using one or more turnbuckles to clamp the bracket to the instrument. The coupler is secured to the bracket and presents receptacles for receiving and connecting a microphone cord to an amplifier sound cord. 
     One embodiment of the invention includes an apparatus for mounting a microphone proximate the sound hole of an instrument, including an elongate, resilient grip, having an upper portion attached to a microphone and a lower portion abutting and held between opposing walls of the sound hole by friction. 
     Another embodiment of an apparatus for mounting a microphone proximate the sound hole of a stringed instrument includes a resilient grip elongate along a longitudinal axis. The grip has an upper portion extending from the midpoint of the grip to the upper end of the grip, and a lower portion extending from the midpoint of the grip to the lower end of said grip. The lower portion of the grip has a width slightly exceeding the width of the section of a sound hole selected for engagement with the lower portion. The grip width dimension is coaxial with the transverse axis of the grip. Means for attaching a microphone to the upper portion include a microphone clip, or a retaining ring or clip attached to or integral with the grip. 
     A further embodiment of the invention includes a method for mounting a microphone in close proximity to the sound hole of an acoustic stringed instrument. The method may include the steps of providing an elongate, resilient grip having a longitudinal major axis and a transverse minor axis, an upper portion at one end of the major axis and a lower portion at the other end of the major axis; attaching a microphone to the upper portion; and wedging the lower portion between opposing walls of the sound hole to fix the microphone in a position proximate to the sound hole. The method may further include the step of aligning the microphone toward the sound hole so that the microphone substantially overlies a proximate portion of the sound hole. The lower portion of the grip may be wedged into position within the sound hole by first squeezing the lower portion to deform it to a width slightly less than the width of the sound hole, inserting the lower portion into the sound hole, and then releasing the lower portion to allow it to expand and exert pressure against the proximate walls of the sound hole. 
     Yet a further embodiment of the invention may include a system for mounting a microphone proximate the sound hole of an instrument. The system may include a generally cylindrical, deformable grip disposed (wedged) within the sound hole of an instrument so as to be in frictional engagement with the adjoining walls of the sound hole; a microphone attached to the upper portion of the grip; a microphone cord in electrical engagement with the microphone at one end and terminating with a microphone cord plug at the other, opposing, end; a coupler engaged with the microphone cord plug; and, means for attaching the coupler to a coupler mounting bracket. The coupler mounting bracket includes an upper member for engaging the front surface of the instrument, proximate to aside of the instrument (and typically proximate the sound hole); a lower member for engaging the back surface of the instrument proximate the same side; and, means for connecting the upper member to the lower member in order to damp the side of the instrument between the members. The means for connecting the upper and lower members may include one or more turnbuckles that may be turned to draw the upper and lower members closer together, thereby creating an effective and easy to use clamping mechanism. The means for attaching the coupler to the coupler mounting bracket may include one or more cable ties, or alternative means such as fabric hook and loop fasteners (commonly sold under the trademark VELCRO®, owned by Velcro Industries B.V.). 
     The terms elongate or elongated are used herein to describe a structure having a major axis and a minor axis such that the structure is elongated along its major axis. The terms longitudinal or longitudinally are used herein to refer to an orientation or alignment of a structure substantially in parallel with, or collinear with, the major axis. The terms transverse or transversely are used herein to refer to an orientation or alignment of a structure substantially in parallel with, or collinear with, the minor axis and perpendicular to the major axis. 
     The term generally cylindrical is used herein to describe an elongate structure with a generally radially symmetrical cross section presenting a shape including circular but also triangular, square, pentagonal, hexagonal, and other polygonal shapes with increased number of sides, and including shapes deviating somewhat from radial symmetry (but generally retaining bilateral symmetry) such as oval and rectangular. 
     The term length is used herein as a measure or indication of distance along the longitudinal axis of a structure. The term width is used herein as a measure or indication of distance along a transverse axis of a structure. The terms coupler and coupling are used interchangeably. The terms microphone connector and microphone plug are used interchangeably. The terms instrument cord and amplifier cord are used interchangeably as referring to the same type of cord in the prior art, often used to connect an instrument&#39;s built in electrical system (such as guitar pickups) to an amplifier, or to connect various sound amplification or modification components to one another. 
     Other advantages of the invention will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example an embodiment of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view of components of the microphone mounting system. 
         FIG. 2  is a top view of a broken away portion of a violin showing a microphone mounted over the violin sound hole and a cable coupler clamped to the side of the violin. 
         FIG. 3  is a diagram showing an elevational view of a tubular, corrugated grip positioned between the impinging walls (shown in cross section) of a sound hole. 
         FIG. 4  is a diagram showing an elevational view of the grip of  FIG. 3  showing the upper portion of the grip held between the jaws of a microphone clip. 
         FIG. 5  is a perspective view of a grip with integral microphone retainer. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As required, a detailed embodiment of the present invention is disclosed herein; however, it is to be understood that the disclosed embodiment is merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. 
     Referring now to  FIGS. 1 through 5  of the drawings, there are shown embodiments of a microphone mounting system indicated by the reference numeral  100 . The main microphone mounting component is a post or grip  105  elongated along its longitudinal axis. The grip  105  is resilient and may comprise a hollow, corrugated plastic tube as shown in  FIGS. 1 ,  3  and  4 . 
     The grip  105  has an upper portion  110  extending from approximately the midpoint  108  to the upper end  112  of the grip  105 . A microphone  125  is typically attached to the upper portion  110  of the grip  105  via a microphone retainer  130  with integral, jawed clip  135 . The lower portion  120  of the grip  105  extends from approximately the midpoint  108  to the lower end  122  of the grip  105  and has a width dimension (e.g. diameter) slightly exceeding the width dimension of the portion of the instrument sound hole  140  selected for engagement with the grip  105 . The lower portion  120  is fitted into the sound hole  140  by squeezing the lower portion  120  to deform it to a grip width dimension slightly less than that of the sound hole  140 , inserting the lower portion  120  into the sound hole  105 , and then releasing the lower portion  120  so it may exert an outwardly biased force against the sides  150  and  155  of said sound hole  140  adjacent to the lower portion  120 , see  FIG. 3 . The grip  105  width dimension may be described as being in a plane perpendicular to the longitudinal axis of the grip  105  or as being coaxial with a transverse axis of the grip  105 . 
     Preferably, the grip  105  is approximately two inches in length for standard violin applications. The length and diameter of the grip  105  can be varied to match the specific instrument. The grip  105  can be shorter and narrower for smaller instruments or longer and wider for larger instruments such as the viola or cello. 
     The cross-sectional width, e.g. diameter, of the grip  105  is generally constant along its length but variations in width are not precluded. The width may vary as long as operability is maintained. For example, the lower portion  120  of the grip  105  may include sections or steps (not shown) of incrementally decreasing diameter approaching the lower end  122  of the grip  105  in order to allow the grip  105  to be readily inserted into sound holes  140  of various dimensions. In the case of a preferred corrugated outer grip surface, the grip  105  varies in diameter from peak  160  to valley  165  of each corrugation (see  FIG. 3 ), but the overall width measured at either the peaks  160  or valleys  165  is generally maintained along the length of the grip  105 . 
     Various materials may be used to form the grip  105 , however, a flexible, hollow, corrugated, plastic tube, including a generally cylindrical wall having an inner surface and an outer surface, offers secure attachment to the sound hole  140  and provides a material that will not damage surface finishes. 
     The grip  105  may comprise elongated, generally cylindrical, tubular and/or foam posts comprising urethane, polypropylene, polyethylene, polyether, polyester, polyvinyl chloride, or butyl-rubber; and/or may comprise one or more elastomers including polyisoprene (natural rubber), butyl rubber, polybutadiene, styrene-butadiene rubber, nitrile rubber, polychloroprene such as neoprene, ethylene propylene rubber, ethylene propylene diene rubber, polyacrylic rubber, silicone rubber, fluorosilicone rubber, fluoroelastomers (such as those sold under the VITON® trademark owned by Dupont Performance Elastomers, LLC), perfluoroelastomers, polyether block amides, chlorosulfonated polyethylene, ethylene-vinyl acetate, polyurethane rubber, elastomeric proteins (protein rubber) such as resilin, and polysulfide rubber. Materials such as extruded or expanded polystyrene foam, natural or synthetic sponge, or wood materials, such as cork, could also be used to form the grip  105 . 
     A lavaliere style microphone  125  may be attached to the grip  105  with a jawed clip (alligator clip)  135  projecting from a retainer  130  that holds the microphone  125  in place. Alternatively, a retainer  205  for holding the microphone  125  may be integral with the body of the grip  200 , as shown in  FIG. 5 , or attached to the grip by other means such as thermal welding, solvent welding, adhesive or, less preferably, mechanical fasteners such as screws or rivets attaching the retainer to the grip. 
       FIGS. 3 and 4  illustrate a grip  105  comprising a circumferentially corrugated, resilient, plastic tube positioned within a sound hole  140 . This corrugated grip  105  embodiment will be specifically referenced herein as grip  170 .  FIG. 3  is an elevational view of the grip  170  with the walls  150  and  155  (shown in cross section) of the sound hole  140  impinging upon the sides of grip  170 , thereby holding the grip  170  in a fixed position within the sound hole  140 . As illustrated, the peaks  160 ′ and valleys  165 ′ of the corrugations proximate the walls  150  and  155  are deformed inward creating multiple angled surfaces that abut the surfaces of the side walls  150  and  155  in frictional and mechanical engagement thereby mitigating any tendency of the grip  170  to slide upward or downward or to lean to one side once put in place by the user. 
       FIG. 4  is an illustration of the grip  170  of  FIG. 3  showing an elevational view rotated approximately 90 degrees about the longitudinal axis of the grip  170  from the view of  FIG. 3 .  FIG. 4  shows the side of one of the sound hole walls  150  in view behind the grip  170  and the upper portion  175  of the grip held between the jaws  180  and  185  of a microphone clip  135 . 
       FIG. 5  provides a perspective view of an alternative embodiment of a grip  105 , denominated herein as grip  200  and including an integral microphone retainer  205 . The retainer  205  comprises a circular ring  210  projecting from a generally cylindrical post  215 . The grip  200  may comprise molded foam rubber, rubber, or plastic, in which case the grip  200  will typically be formed (e.g. injection molded) as a single piece. Alternatively, the ring  210  may be connected at the neck  220  to the post  215  using thermal welding, solvent welding, adhesive or, less preferably, mechanical fasteners such as screws. In use, a microphone  125  is slipped into the aperture  212  of the retainer  205  and the post  215  is fitted into the instrument, sound hole  140 . The post  215  may have a bore  217  therethrough, as shown in  FIG. 5 , or may be solid if formed of a highly resilient material such as foam rubber. 
     In  FIG. 2 , an instrument cable coupler  250  is attached to the bass or bottom left side of an instrument such as a violin  300 . The coupler  250 , also shown in  FIG. 1 , allows for connection of one electrical sound signal cable to another and passage of electrical signals therebetween. The coupler  250  will typically have a ¼ inch diameter female receptor  255  on one side to accept a standard ¼ inch plug from a typical instrument cable (not shown) used for connecting instrument electrical systems to amplifiers. The coupler  250  will typically have a ⅛ inch receptor  260  on the opposing side to accept a standard ⅛ inch plug  265  from a typical microphone cable  270 . Other, non-standard sizes of couplers and plugs may readily be used as well, as long as a coupler with appropriately sized receptors is selected to match the cable plugs in use. 
     A shown in  FIG. 2 , the microphone cable connector or plug  265  is plugged into the top of the cable coupler  250 . The microphone cable plug  265  can be 90 degree plug, as shown in  FIG. 1 , or a straight plug. A typical microphone assembly  280  includes a microphone on/off switch  285  disposed between the microphone  125  and the plug  265  with the microphone cable  270  connecting the plug  265  to the switch  285  and then the switch  285  to the microphone  125 . An alternative microphone assembly may omit the microphone on/off switch  285 , however, inclusion of the microphone on/off switch  285  is a superior design as this allows the microphone  125  to be readily turned off when not in use. One end of an amplifier cable may now be plugged into the bottom receptor  255  of the cable coupler  250  and the other end to an amplifier or other sound system component (not shown). 
     The coupler  250  may be conveniently mounted on the side of an instrument (e.g. violin  300 ) using a coupler mounting bracket  305 . The coupler mounting bracket  305  is clamped to the side of the body of a violin  300 , typically upward of the chin rest  310  and proximate the sound hole  140 .  FIG. 1  shows a coupler mounting bracket  305  in partially exploded view.  FIG. 2  shows atop view of the bracket  305  mounted upon the left bass side  315  of a violin  300 . 
     The bracket  305  typically comprises a lower clamping member  320  for engaging the back surface (not shown) of the violin  300  and an upper clamping member  325  for engaging the front surface. A bracket main body  350 , against which a coupler  250  is held when in position upon the bracket  305 , depends from the upper clamping member  325 . The upper and lower clamping members  325  and  320  are joined to one another by a pair of upright members  330  and  335  disposed parallel to one another and generally perpendicular to the lower surface of the upper clamping member  325 . The upright members  330  and  335  have means for varying their length, such as turnbuckles  340  and  345 , so that the upper and lower clamping members  325  and  320  may be drawn together and against the adjoining surfaces of the violin  300 , thereby sandwiching the violin  300  between the clamping members  320  and  325  and holding the coupler mounting bracket  305  in a fixed position upon the violin  300 . An example of a similar type of bracket, though used for a different purpose, which includes turnbuckles is given in U.S. Pat. No. 904,258 to Henrikson et al., the disclosure of which is incorporated herein by reference. 
     The upper and lower clamping members  325  and  320  of the coupler mounting bracket  305  may comprise wood, plastic, acrylic, metal or composite material. Typically, the coupler mounting bracket  305  is one inch wide and two and one half inches long. The upper member  315  is typically two inches wide at the top and rests on the top of the violin  300  while the upright members  330  and  335  and are positioned along the side  315  of the instrument body. The coupler mounting bracket  305  dimensions may be readily determined through reference and adaptation to the dimensions of a standard violin. Various instrument sizes and shapes may be accommodated through adjustment of the bracket turnbuckles  340  and  345 . 
     Other methods of attaching the coupler bracket  305  to an instrument include attaching the upper and lower members  320  and  325  to each other using standard nuts and bolts, or threading bolts through holes in either the upper or lower member and then into threaded engagement with tapped holes in the opposing member. The turnbuckle assembly offers the advantage of being easily installed and of a familiar design to violinists. 
     The coupler  250  may be attached to the coupler mounting bracket  305  with cable ties  355  or any operative alternate method of attachment such as glue, bolts, screws, clamps, fabric hook and loop fasteners, or tape. An advantage to mounting the coupler  250  with cable ties  355  is that this allows the microphone on/off switch  285  to be clipped to a cable tie  355  and provides a secure mounting method for the microphone on/off switch  285 . Often, microphone on/off switches  285  in the prior art are provided with spring clips  290  for the purpose of securing the switch  285  in a fixed location, such as on the clothing of a wearer if the microphone  125  was constructed for use as a clip-on lavaliere microphone for voice amplification. 
     An alternate embodiment omits the cable coupler  250  from the system and merely uses a long cable from the microphone  125  to plug directly into the amplification system. The cable coupler  250 , however, is typically an integral part of the mounting system since attachment of the cable coupler  250  to the body of the instrument  300 , and plugging the microphone cable  270  and amplifier cable into the coupler  250  provides stability and support for the microphone  125 . Without the cable coupler  250  the weight of the microphone cable  270  itself might pull the microphone  125  out of the selected position at the sound hole  140  or perhaps even pull the microphone  125  and grip  305  from the instrument entirely. 
     In use, the grip  105  is squeezed or compressed slightly so it will fit easily into the instrument sound hole  140 . The grip  105  is oriented so that it stands vertical relative to a horizontally disposed (prone) instrument  300  as shown in  FIG. 2 . Once the grip  105  is inserted into the sound hole  140 , it is released. When the grip  105  is released and returns to its original shape it is held tightly in place within the instrument&#39;s sound hole  140  by friction augmented by an outwardly biased, lateral force exerted by the grip  105  against the proximate walls  150  and  155  of the sound hole  140 . If provided with corrugations in the lower portion  120 , the grip&#39;s corrugations keep the grip  105  from falling over and allow the grip  105  to be easily repositioned in the sound hole  140  for desired results. If provided with corrugations in the upper portion  110 , the grip&#39;s corrugations also help the microphone clip  135  to retain its hold upon the grip  105 . Before or after installing the grip  105  into the sound hole  140 , the bracket  305  is clamped onto the violin side  315  by turning the turnbuckles  340  and  345  until they are sufficiently tightened to retain the bracket  305  in fixed position while the violin  300  is in use. One end of the amplifier cable is then plugged into the coupler  250 , and the other into an amplifier or other sound system component. The microphone cable is then also plugged into the coupler. The microphone switch is turned on, as is the sound system/amplifier, and the instrument may then be played with the sound being received by the microphone and amplified for listening, recording or broadcast. 
     An important advantage of the present invention, as demonstrated in the disclosed embodiments, is that it is a removable, non-invasive microphone mounting system  100 . The microphone  125  and grip  105  can be removed while the mounting bracket  305  and coupler  250  may be left in place making for very fast and easy installation and removal. Since the entire system  100  is removable it may easily be used on multiple instruments. 
     It is to be understood that while certain forms of this invention have been illustrated and described, it is not limited thereto except insofar as such limitations are included in the following claims and allowable equivalents thereof.