WO2011085262A1

WO2011085262A1 - Pitch shifting device for musical instruments

Info

Publication number: WO2011085262A1
Application number: PCT/US2011/020595
Authority: WO
Inventors: Daniel P. Baroux; Alexander J. Stevenson; Robert Hubbard
Original assignee: Flamehalt Technologies, Inc.
Priority date: 2010-01-08
Filing date: 2011-01-07
Publication date: 2011-07-14

Abstract

An adjustment module, which is for use with a musical instrument that provides an initial analog audio signal, may include an analog-to-digital converter for converting the initial analog audio signal into a digital audio signal, wherein the initial digital audio signal has a pitch; a processor for changing the pitch of the initial digital audio signal and thereby creating a pitch-adjusted digital audio signal; a user interface in communication with the processor for allowing the user to control the changing of the pitch of the initial digital audio signal; and a power supply for providing electrical power to at least one of the analog to digital converter and the processor. The adjustment module may further include a digital-to-analog converter for converting the pitch-adjusted digital audio signal to a pitch-adjusted analog audio signal having a different pitch than the initial analog audio signal.

Description

PITCH SHIFTING DEVICE FOR MUSICAL INSTRUMENTS

INCORPORATION BY REFERENCE

The entire disclosure of U.S. Provisional Application No. 61/293,400, which was filed on January 8, 2010, is incorporated herein by reference.

BACKGROUND

This disclosure relates to electronically changing audio signals produced by musical instruments and, more particularly, to electronically changing the pitch of audio signals produced by musical instruments.

Musical instruments when played either emit audible sound or an electronic signal. This audible sound or electronic signal may or may not be relayed through speakers or amplification devices. In 1936 the American Standards Association recommended that the A above middle C on a piano be tuned to 440 Hz. This Standard was taken up by the International Organization for Standardization in 1955 and was reaffirmed by them in 1975 as ISO 16. The purpose of this was to standardize the audio frequency calibration in the manufacturing of musical instruments. This standardization however has not been adopted in all countries. In addition, this standardization is only a recommendation and not Law.

Musicians, music producers, music engineers, composers, or anyone playing an instrument has the ability to alter this standard pitch reference on their instrument or recording to suit their playing needs at anytime. The pitch may be intentionally changed for a variety of reasons including but not limited to, modifying the physical properties of the instrument to attain a particular sound or modify the instrument's tonal characteristics, or to match the pitch of a prerecorded musical work, or to match the pitch of other instruments in a band or orchestra which as a group may be employing a non-standard tuning reference. Also, a musician may tune their instrument 'by ear' without the aid of a physical reference such as an electronic tuner, pitchfork, etc. This may result in the instrument being tuned to a pitch either above or below the 440HZ reference.

The pitch reference of most acoustic and stringed instruments can also be unintentionally altered by environmental conditions due to changes in temperature and humidity. Stringed instruments also have a tendency to 'drift' out of tune over time as the string tension changes due to stretching, aging, and deterioration of the strings over time. A guitar, for example, may be tuned at any pitch the player may choose. When tuned, this guitar may be tuned at 460 Hz for example. However if playing at this 460 Hz pitch is desired and other instruments are playing with a different pitch such as the standardized 440 Hz pitch, the combined sound will not be in tune as the pitches are different. In order to create a harmonized sound, it is usually desirable to tune all instruments to the same pitch.

Continuing the previous example, while playing a guitar along to a prerecorded piece of music, if the guitar is tuned to 460 Hz and the prerecorded music was recorded at a pitch of 440 Hz, then the combined sound will be out of tune. To correct this, the guitar player must change the tuning of the guitar by turning the tuning pegs of the guitar to adjust the tension in the strings, in this case lowering them down to the prerecorded music's 440 Hz reference. Once the guitar tune is adjusted the combined sound will be in the same pitch and in tune with the prerecorded piece of music.

If playing along with successive musical recordings, a guitar player may find that each recording they are playing along with has a slightly different pitch causing them to retune the guitar differently for every song played. This constant retuning becomes a tedious and frustrating task.

Electronic devices exist that take the output signal from an electronic instrument or device and change its pitch, such as Digitech's Intelligent Pitch Shifter. This device may also add to the instrument's native sound by creating an electronic harmonic sound in addition to the original pitch of the instrument. Digitech's Pitch Shifter is a large device and is typically packaged into 'effect racks', is relatively expensive, is not easily portable, and is not battery powered.

Digitech also manufactures a product called the Digitech Whammy. This device is a foot pedal device powered by batteries and is primarily used for electric guitars and basses. By using your foot to change the position of the treadle, you can alter the pitch of the output signal of your guitar. This device is primarily an effects pedal and not primarily intended to be used for pitch adjustment for tuning purposes.

Electronic MP3 or CD portable devices such as the TASCAM MP-GT1 guitar trainer exist whereby the operator may change the pitch of the prerecorded music loaded onto the MP3 or CD device to be electronically pitch altered on playback to match the pitch of the instrument.

The Gibson Dusk Tiger or Dark Fire guitars include intelligent adjustment knobs in the body of the guitar to adjust pitch or tuning, however this pitch adjustment causes a mechanical adjustment of the tuning pegs through the use of electronic signals, and servomotors and gear assemblies. These types of pitch adjustment mechanisms may be considered to be relatively expensive.

There is a desire for an electronic adjustment module that provides a new balance of properties.

SUMMARY

One aspect of this disclosure is the provision of an adjustment module (e.g., a pitch-adjustment module) for use with a musical instrument that provides an analog audio signal. The adjustment module may include an analog-to-digital converter for converting the initial analog audio signal into a digital audio signal; a processor for changing (e.g., raising and lowering) the pitch of the initial digital audio signal and thereby creating a pitch-adjusted digital audio signal; a user interface in communication with the processor for allowing the user to control the changing of the pitch; and a power supply (e.g., batteries) for providing electrical power to at least one of the analog-to-digital converter, the processor and the user interface. The adjustment module may further include a digital-to-analog converter for converting the pitch-adjusted digital audio signal to a pitch-adjusted analog audio signal having a different pitch than the initial analog audio signal. The pitch-adjusted analog audio signal may be provided to a peripheral component, such as, but not limited to, an audio recorder, or an amplifier and speaker.

In accordance with some aspects of this disclosure, the adjustment module may be mounted to the musical instrument (e.g., at least partially within and/or at least partially external to the musical instrument), or the adjustment module may be positioned remotely from, yet be electrically connected to, the musical instrument.

Other aspects of this disclosure will become apparent from the following.

BRIEF DESCRIPTION OF THE DRAWINGS

Having described some aspects of this disclosure in general terms, reference will now be made to the accompanying drawings, which illustrate exemplary aspects of this disclosure, are not necessarily drawn to scale and are schematic, and wherein:

Fig. 1 is a block diagram illustrating an adjustment module (e.g., a pitch- adjustment module), in accordance with an embodiment of this disclosure.

Fig. 2 illustrates the adjustment module incorporated at least partially into an interior chamber of a musical instrument, wherein the musical instrument is partially cut away, and the musical instrument is connected to a peripheral component, such as an audio recorder, or an amplifier and speaker, in accordance with one aspect of this disclosure.

Fig. 3 illustrates that the adjustment module is at least partially mounted to the exterior of a conventional musical instrument (which is partially cut away), and that the adjustment module is connected to peripheral component(s), such as an audio recorder, or an amplifier and speaker, in accordance with another aspect of this disclosure.

Fig. 4 illustrates that the adjustment module is connected between a conventional musical instrument (which is partially cut away) and peripheral component(s), such as an audio recorder, or an amplifier and speaker, in accordance with still another aspect of this disclosure.

DETAILED DESCRIPTION

The present disclosure now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all aspects of the disclosure are shown. Indeed, this disclosure may be embodied in many different forms and should not be construed as limited to the aspects set forth herein; rather, these aspects are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.

Referring now in greater detail to the drawings, in which like numerals refer to like parts throughout the several views, an adjustment module 10 (e.g., a pitch-adjustment module) of an embodiment of this disclosure is shown in Fig. 1. Generally described and as will be discussed in greater detail below, in accordance with one aspect of this disclosure, the adjustment module 10 is operative for changing (i.e., raising and lowering) the pitch of an electronic audio signal from a musical instrument that is being played, such that the adjustment module creates a pitch-adjusted audio signal.

Referring in more detail to Fig. 1, the adjustment module 10 includes an input interface 12 in electrical communication with (e.g., electrically wired to) an analog-to- digital converter 14, a processor 16 in electrical communication with both the analog-to- digital converter 14 and a digital-to-analog converter 18, and an output interface 20 in electrical communication with the digital-to-analog converter 18. The converters 14, 18 and processor 16 may be any converters and processor that are suitable for cooperatively performing so that the adjustment module can function as described herein. For example, the processor 16 may be in the form of a computer (which may include appropriate input and output devices, a processor, memory, software module(s), etc.), a computer processor and/or any other suitable device(s). The processor 16 may be controlled by suitable software modules and/or firmware, or the like, or in any other suitable way, so that the processor is operative for changing (i.e., raising and lowering) the pitch of a digital audio signal, as discussed in greater detail below.

The adjustment module 10 further includes a user interface 22 in electrical communication with the processor 16, such as for allowing the user (e.g., the user playing the musical instrument associated with the adjustment module) to control at least the changing of (e.g., the setting of) the pitch of the digital audio signal. Typically one or more of the converters 14, 18, processor 16 and user interface 22 require electrical power in order to operate. Accordingly, the adjustment module 10 typically further includes an electrical power supply 24 in electrical communication with one or more of the converters 14, 18, processor 16 and user interface 22. The electrical power supply 24 may be in the form of a battery or batteries, or alternatively may be wiring or a circuit, or the like, for being connected to (e.g., plugged into) any suitable source of power that is available (e.g., an electrical outlet external to the adjustment module).

Optionally, the components of the adjustment module 10 may be contained in / may be mounted within a substantially self-contained, substantially fully-enclosed housing 26 of the adjustment module (or another housing (e.g., the housing of a musical instrument), as discussed below). Any housing 26 of the adjustment module 10 may include one or more access openings for, for example, providing access to one or more of the power supply 24, electrical interfaces 12, 20 and user interface 22. As one example, the user interface 22 may include one or more movable control members 28 (e.g., a rotatable control knob, linear slide knob, depressible peddle, switch lever, switch button, or any other suitable movable member) that project outwardly from the housing 26, for being accessible at an exterior of the housing so as to be readily manually movable by the user for controlling the changing of (e.g., the setting of) the pitch.

Referring to Fig. 2 and in accordance with one aspect of this disclosure, the adjustment module 10 may be integrated into the body of the electrical instrument, and the electrical instrument may be, but is not limited to, an electric guitar 30. A substantial portion of the guitar 30 is cut away in Fig. 2 (e.g., in order to schematically show internal components of the guitar). The electric guitar 30 may be conventional, except for having the adjustment module 10 integrated thereinto. As schematically shown in Fig. 2 and generally described, the guitar 30 includes a neck 32 mounted to a body 34. As shown in Fig. 2, the adjustment module 10 is mounted within an interior chamber of the body 34, except that the movable control member 28 (e.g., rotatable control knob) extends through a hole in the front face of the body 34, so as to be readily accessible to the person playing the guitar 30, so that the person playing the guitar may manually adjust the control member to control the adjustment member and thereby the pitch.

In accordance with one aspect of this disclosure, the adjustment module 10 allows the user of the guitar 30 to alter (i.e., increase or decrease) the pitch of the audio signal that is available for being electrically transmitted from the guitar as compared to the pitch of the more original (e.g., upstream) audio signal of the guitar. That is, the adjustment module 10 is operative for providing a "pitch shift" between the audio signal that is available for being electrically transmitted from the guitar and the more original (e.g., upstream) audio signal of the guitar. In accordance with another aspect, the adjustment module 10 is operative so that the pitch shift occurs in real time (e.g., the pitch shift occurs very quickly so that it is not (e.g., substantially is not) discernable by the user of the guitar and/or any delay that takes place in carrying out the pitch shift is no more than about 7 milliseconds, is less than about 7 milliseconds, is less than about 6 milliseconds, is less than about 5 milliseconds, is in a range from about 0 milliseconds to about 7 milliseconds, and/or is in a range from about 1 millisecond to about 7 milliseconds.

Ends of strings 35 (e.g., vibratable members) are mounted to the front face of the body 34, and the opposite ends of the strings are mounted to posts / geared mechanisms 36 that may be manually manipulated by way of thumb screws 37 to manually adjust the tension in the strings and thereby adjust the pitch of the music produced by the guitar 30. Adjusting the geared mechanisms 36 may be characterized as re-tuning the guitar 30. In contrast, the adjustment module 10 makes no changes to the tension in the strings 36, and thus does not do any mechanical re-tuning, as will be discussed in greater detail below.

The strings 35 extend across at least one transducer / at least one magnetic pickup 38 mounted at the front face of the body 34. Pickup coil(s) of the magnetic pickup(s) 38 are part of a conventional electronic circuit 40 for providing an analog audio signal (e.g., an initial analog audio signal). The circuit 40 may be any suitable electric guitar circuit. For example, the circuit 40 may include conventional tone adjustment and amplitude adjustment modules 42, 44 that each include a rotatable control knob 45, or any other suitable movable control member, that extends through a hole in the front face of the body 34, so as to be readily accessible to the person playing the guitar 30 for adjustment purposes. As schematically shown in Fig. 2, the output of the circuit 40 is electrically connected to the input 12 of the adjustment module 10. Referring also to Fig. 1 and in accordance with one example of a method of operation of the adjustment module 10, the analog-to-digital converter 14 receives the initial analog audio signal from the circuit 40, and converts the initial analog audio signal from the circuit 40 into a digital audio signal. In response to instruction from the user interface 22 (e.g., the position of the control member 28), the processor 16 changes (i.e., raises and/or lowers) the pitch of the initial digital audio signal and thereby creates a pitch-adjusted digital audio signal. The digital- to-analog converter 18 converts the pitch-adjusted digital audio signal to a pitch-adjusted analog audio signal having a different pitch than the initial analog audio signal produced by the electronic circuit 40.

In accordance with one example, the pitch-adjusted analog audio signal provided at the output 20 of the adjustment module 10 may be substantially the same as the initial analog audio signal provided by the circuit 40, except for the change in pitch. For example, the tone of the pitch-adjusted analog audio signal provided at the output 20 of the adjustment module 10 may be substantially the same as the tone of the initial analog audio signal provided by the circuit 40. Similarly, the initial digital audio signal provided by the analog-to-digital converter 14 may be substantially the same as the digital audio signal provided by the processor 16, except for the change in pitch. For example, the tone of the initial digital audio signal provided by the analog-to-digital converter 14 may be substantially the same as the tone of the digital audio signal provided by the processor 16.

Referring to Figs. 1 and 2, the output 20 of the adjustment module 10 is electrically connected to an electrical output of the guitar 30, which may be in the form of a jack 46 or any other suitable connector, or the like. Accordingly, jack 46 receives the pitch-adjusted analog audio signal from the adjustment module 10 / digital-to-analog converter 18. A cable 48 may be plugged into the jack 46 so that the pitch-adjusted analog audio signal may be provided to one or more peripheral components 50 such as, but not limited to, an audio recorder, or an amplifier connected to speaker(s).

Fig. 3 schematically illustrates another aspect of this disclosure, in which the adjustment module 10 is at least partially mounted to the exterior of a musical instrument, and the musical instrument is a conventional electric guitar 130. A substantial portion of the guitar 130 is cut away in Fig. 3 (e.g., to schematically show internal components). The guitar 130 includes a neck 132 mounted to a body 134. Ends of strings 135 (e.g., vibratable members) are mounted to the front face of the body 134, and the opposite ends of the strings are mounted to posts / geared mechanisms 136 that may be manually manipulated to manually adjust the tension in the strings and thereby adjust the pitch of the music produced by the guitar 130. The strings 135 extend across at least one magnetic pickup 138 (e.g., a transducer) mounted at the front face of the body 134.

Pickup coil(s) of the magnetic pickup 138 are part of a conventional electronic circuit 140 for providing an initial analog audio signal. The circuit 140 may be any suitable electric guitar circuit. For example, the circuit 140 may include conventional tone adjustment and amplitude adjustment modules 142, 144 that each include a rotatable control knob 145, or any other suitable movable control member, that extends through a hole in the front face of the body 134, so as to be readily accessible to the person playing the guitar 130 for manual adjustment. As schematically shown in Fig. 3, the output of the circuit 140 is electrically connected to an electrical output of the guitar 130, which may be in the form of a jack 146 or any other suitable connector, or the like.

As shown in Fig. 3, the input interface 12 of the adjustment module 10 may be in the form of a plug 12' that is fixedly connected to and extends rigidly from the housing 26 of the adjustment module 10. Accordingly, the adjustment module 10 receives the initial analog audio signal from the circuit 140 by way of the plug 12'. Alternatively, the input interface 12 may be in any other suitable configuration.

In accordance with one aspect of this disclosure, the configurations of the plug 12' and the jack 146 may be such that there is an interference fit / press fit / friction fit, or the like, respectively therebetween. As a result, the adjustment module 10 may be releasably mounted to (substantially mounted to) or at least partially mounted to the guitar 130 by way of the plug interface 12' being interference fit / press fit / friction fit, or the like, into the jack 146, as shown in Fig. 3.

In addition or alternatively, one or more releasable straps 51 or other releasable fasteners, or any other suitable attachment mechanism, may be used to attach the adjustment module 10 to the guitar 130. In addition or alternatively, the adjustment module 10 may be releasably or more permanently mounted to the guitar 130 with mechanical fastener(s) and/or adhesive material. Irrespective of how the adjustment module 10 is mounted to the guitar 130, typically the one or more movable control members 28 (e.g., rotatable control knob, linear slide knob, depressible peddle, switch lever, switch button, or any other suitable movable member) will be readily accessible to the person playing the guitar 130. As shown in Fig. 3, the output interface 20 of the adjustment module 10 may be in the form of a jack 20'. Accordingly, The cable 48 may be plugged into the jack 20' so that the pitch-adjusted analog audio signal may be provided from the adjustment module 10 to one or more peripheral components 50 (e.g., an audio recorder and/or or an amplifier connected to speaker(s)). Alternatively, the output interface 20 of the adjustment module 10 may be in any other suitable configuration.

As schematically shown in Fig. 3, the adjustment module 10 is extremely portable. Also and as will be understood by those of ordinary skill in the art, the adjustment module 10 can provide the pitch shift discussed above with reference to Fig. 2 while it is in the configuration shown in Fig. 3, and while it is in any other suitable configuration or location, such as the location shown in Fig. 4.

Fig. 4 schematically illustrates another aspect of this disclosure, in which the adjustment module 10 is positioned more remotely from the guitar 130, such as upon a floor 52 or another suitable surface, or in any other suitable location. For example, when the adjustment module 10 is upon the floor 52, or the like, the one or more movable control members 28 of the module 10 may be in the form of depressible peddles, or any other suitable controllable members.

As shown in Fig. 4, each of the input and output interfaces 12, 20 may be in the form of a jack 12", 20", although any other suitable interfaces may be used. Accordingly, cables 48 may be respectively plugged into the jacks 12", 20" to connect the adjustment module 10 between the guitar 130 and one or more peripheral components 50 (e.g., an audio recorder and/or or an amplifier connected to speaker(s)). As a result, the adjustment module 10 receives the initial analog audio signal from the guitar 130 by way of the input jack 12", and provides the pitch-shifted analog audio signal to the one or more peripheral components 50 by way of the output jack 20".

A wide variety of musical instruments are within the scope of this disclosure. That is, those of ordinary skill in the art will understand that electric guitars are only one example of musical instruments that are within the scope of this disclosure. Indeed, one of ordinary skill will understand that the present disclosure is not limited to musical instruments with strings. For example and not limitation, a wide variety of musical instruments include one or more vibratable members that may be associated with a magnetic pickup and appropriate circuit for producing an initial analog audio signal suitable for processing by the adjustment module 10. In addition, the adjustment module 10 may be varied to accommodate for different instruments and/or peripheral components 50. For example, if an electrical musical instrument provides a digital audio signal, the inclusion of the analog-to-digital converter 14 of the adjustment module 10 may be optional (e.g., may be omitted). As another example, if a peripheral component 50 is adapted for receiving digital audio signals, the digital-to-analog converter 18 of the adjustment module 10 may be optional (e.g., may be omitted).

In accordance with one aspect of this disclosure, the adjustment module 10 may be a battery-powered electronic device that may be plugged directly into an instrument, such as a guitar, as an external attachment, or the adjustment module 10 can be integrated into the body of the instrument, with the instrument externally presenting the control member 28 in the form of an adjustment knob that looks similar to a control knob commonly found on electric or electrified acoustic instruments.

In one aspect, the adjustment module 10 takes the electronic audio signal normally sent out to external amplification or recording devices, isolates this signal and electronically digitizes the sound with or without added effects, by employing a digital process in response to user input by way of the user interface 22. This user input by way of the user interface 22 may be by way of rotation of an adjustment knob, or by way of touch input devices, examples of which include a touchpad, a touch sensitive LCD display screen, or joystick. The adjustment module 10 can either raise or lower the pitch of the digitized signal in response. Whereas an aspect of this disclosure is for the adjustment module 10 to primarily adjust the pitch, optionally the sound may also be altered by adding sound effects to the digitized signal.

According to one aspect of this disclosure, the adjustment module 10 can be switched on or off (e.g., by way of the user interface 22, or more particularly by way of an on/off switch that is part of, or otherwise provided by, the user interface). When the adjustment module 10 is imbedded in the instrument and while the adjustment module is "off, the audio signal typically will not be affected by the adjustment module and will travel directly (pass-thru) to the electronic output of the instrument as normal and as if the adjustment module did not exist. When "on", the adjustment module will be enabled the user to affect the pitch of the output signal, for example in response to the user rotating an adjustment knob (of the user interface 22) either clockwise or counter clockwise, or by interacting with one or more of the alternative touch input devices (of the user interface 22). The result is that the sound of the instrument coming out of the speaker(s) of the peripheral component 50 will be different than that sound emitted directly by the instrument. The adjustment module 10 does not physically alter the tuning of the instrument, but only alters the electronic output signal. A digital read out of the pitch/Hz can be displayed on a display device (of the user interface 22) placed anywhere on the body of the instrument or integrated into the adjustment module 10. This display may also allow the user to interact with the adjustment module 10 to employ other sound enhancements or features that may optionally be included in the adjustment module, or to observe the current settings and status of the adjustment module, such as the status of the power supply 24 (e.g., the remaining battery life).

Optionally, the adjustment module 10 may make other adjustments available to the user for such functions as calling up predefined pitch shift increments, sound enhancements or effects modifications, and the adjustment module optionally may have several indicator lights to indicate which mode or sound modification setting the adjustment module is set to.

One aspect of this disclosure is the provision of an adjustment module 10 for allowing a user to 'dial up' a temporary pitch alteration and leave it there for the duration of a musical performance. In addition, there may be additional desirable pitch alterations that are possible with the adjustment module 10. For example, the adjustment module 10 may emulate a vibrato-equipped guitar (the vibrato is also called a 'whammy bar') where the user can interact with one or more of the touch input devices of the user interface 22 to cause the adjustment module 10 to dynamically apply pitch changes in proportion to and in response to the user's interactions with the touch input device(s).

Many modifications and other aspects of the disclosure set forth herein will come to mind to one skilled in the art to which this disclosure pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the disclosure is not to be limited to the specific aspects disclosed and that modifications and other aspects are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

WHAT IS CLAIMED IS:

1. A musical instrument for being played by a user, the musical instrument comprising:

a body;

a vibratable member mounted to the body for being vibrated;

an electronic circuit that is mounted to the body, wherein the electronic circuit includes a transducer configured for being responsive to vibration of the vibratable member, and the electronic circuit is for producing an initial analog audio signal in response to vibration of the vibratable member; and

an adjustment module mounted to the body and in electrical communication with the electronic circuit, the adjustment module including

an analog-to-digital converter for converting the initial analog audio signal into an initial digital audio signal, wherein the initial digital audio signal has a pitch,

a processor for changing the pitch of the initial digital audio signal and thereby creating a pitch-adjusted digital audio signal,

a user interface in communication with the processor for allowing the user to control the changing of the pitch of the initial digital audio signal, and

a power supply for providing electrical power to at least one of the analog- to-digital converter, the processor and the user interface.

2. The musical instrument according to claim 1, wherein:

each of the initial digital audio signal and the pitch-adjusted digital signal have a tone, and

the processor is operative so that the tone of the initial digital audio signal is substantially the same as the tone of the pitch-adjusted digital signal.

3. The musical instrument according to claim 1, wherein the adjustment module further includes a digital-to-analog converter for converting the pitch-adjusted digital audio signal to a pitch-adjusted analog audio signal having a different pitch than the initial analog audio signal produced by the electronic circuit.

4. The musical instrument according to claim 3, wherein: each of the initial analog audio signal and the pitch-adjusted analog signal have a tone, and

the adjustment module is operative so that the tone of the initial analog audio signal is substantially the same as the tone of the pitch-adjusted analog signal.

5. The musical instrument according to claim 3, further comprising an electrical connector mounted to the body and in communication with the adjustment module for connecting the musical instrument to an external device for receiving the pitch-adjusted analog audio signal.

6. The musical instrument according to claim 1, wherein the user interface comprises a movable member accessible at an exterior of the body for being manually moved by the user for controlling the changing of the pitch of the initial digital audio signal.

7. The musical instrument according to claim 6, wherein the movable member is a rotatable control knob that projects outwardly from an exterior of the body.

8. An adjustment module for use with a musical instrument that provides an initial analog audio signal, the adjustment module comprising:

an analog-to-digital converter for converting the initial analog audio signal into a digital audio signal, wherein the initial digital audio signal has a pitch;

a processor for changing the pitch of the initial digital audio signal and thereby creating a pitch-adjusted digital audio signal;

a user interface in communication with the processor for allowing the user to control the changing of the pitch of the initial digital audio signal; and

a power supply for providing electrical power to at least one of the analog-to- digital converter, the processor and the user interface.

9. The adjustment module according to claim 8, wherein:

each of the initial digital audio signal and the pitch-adjusted digital signal have tone, and

10. The adjustment module according to claim 8, wherein the adjustment module further includes a digital-to-analog converter for converting the pitch-adjusted digital audio signal to a pitch-adjusted analog audio signal having a different pitch than the initial analog audio signal.

11. The adjustment module according to claim 10, wherein:

each of the initial analog audio signal and the pitch-adjusted analog signal have a tone, and

12. The adjustment module according to claim 8, wherein the user interface comprises a movable member accessible at an exterior of the adjustment module for being manually moved by a user for controlling the changing of the pitch of the initial digital audio signal.

13. The adjustment module according to claim 12, wherein the movable member is a rotatable control knob that projects outwardly from the adjustment module.

14. A method of processing sound of a musical instrument, comprising: obtaining an initial analog audio signal from the musical instrument;

converting the initial analog audio signal into a digital audio signal, wherein the initial digital audio signal has a pitch; and

changing the pitch of the initial digital audio signal and thereby creating a pitch- adjusted digital audio signal having a pitch that differs from the pitch of the initial digital audio signal.

15. The method according to claim 14, wherein the initial digital audio signal has a tone, and the changing of the pitch is carried out so that the pitch-adjusted digital audio signal has a tone that is substantially similar to the tone of the initial digital audio signal.

16. The method according to claim 14, comprising converting the pitch- adjusted digital audio signal to a pitch-adjusted analog audio signal having a different pitch than the initial analog audio signal.

17. The method according to claim 16, comprising driving a speaker with the pitch-adjusted analog audio signal by way of an amplifier.