WO1996016398A1

WO1996016398A1 - Device for the assembly and identification of chords in fretted stringed instruments such as guitars, electric guitars and the like and the respective methods of assembly and identification

Info

Publication number: WO1996016398A1
Application number: PCT/BR1995/000051
Authority: WO
Inventors: Claudio Mariano Vaz; Celia Maria Carvalho Vaz
Original assignee: Claudio Mariano Vaz; Celia Maria Carvalho Vaz
Priority date: 1994-11-21
Filing date: 1995-11-17
Publication date: 1996-05-30
Also published as: BR9404669A

Abstract

A device for the assembly and identification of chords in fretted stringed instruments such as guitars, electric guitars and the like, and the respective methods of assembly and identification, comprised essentially of a slide-rule (1) with the musical intervals that make up the chords, arranged in between themselves on the same position they show on the finger board of the instrument, that slides on a fixed base (2) with windows (21) for viewing the intervals. For each tonic note the slide-rule is adjusted on the fixed base in such way that all the intervals that make up one or more types of chords are visible through the windows in the given base, on the same positions they present on the instrument's finger board. This way, it is possible to visualize directly on the device the several possible chord fingerings, transpose them to the instrument and vice-versa.

Description

DEVICE FOR THE ASSEMBLY AND IDENTIFICATION OF CHORDS IN FRETTED STRINGED INSTRUMENTS SUCH AS GUITARS, ELECTRIC GUITARS AND THE LIKE AND THE RESPECTIVE METHODS OF ASSEMBLY AND IDENTIFICATION. BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a device for the assembly and identification of chords in fretted stringed instruments such as guitars, electric guitars and the like, through the visualization of the relative and absolute location of musical intervals on the instrument's finger board and its respective methods of utilization.

2. Description of the Prior Art

The chords are made up of two or more musical notes taken from the chromatic scale. Each note of the chord may be characterized by step and half step interval or intervals that exist between the given note and the tonic note or degree "1" of the chord. In this way, each note of a chord receives a notation referring to the interval where it is located in relation to degree "1" of the chord. For example, a chord in "G" Major is made up by the note "Sol" or "G", corresponding to the degree "1", by the note "Si" or "B", corresponding to the major third interval, "3M" , and the note "Re" or "D", corresponding to the perfect fifth interval, "5J". A Major chord relative to a tonic note other than "G" will also be made up by the degree "1" and the intervals, "3M" and "5J", being however, such intervals relative to musical notes different from the previous case. Hence, the intervals define the relative locations between the notes that, make up the chords. To the set of intervals that make up a given chord, it is given the name of chord formula, ft chord is therefore defined by its chord formula, that is responsable for the definition of the relative location between the notes, and by the tonic note, responsable for defining the absolute location of the notes in the chromatic scale. In another way, a same note can correspond to any interval, depending on the tonic note of the chord.

The neck of string instruments of the kind of guitars, electric guitars and the like, from hereon referred only as instrument, are divided by frets that determine, for each string, a sequence of notes of the chromatic scale, separated between themselves by one half-tone. In this way, each string fret on the instrument's finger board correspond to a musical note and, at the same time, may correspond to any interval, depending on the tonic note of the chord under study.

The assembly of chords in the instrument, as well as the identification of the chord symbol from a given string fingering on the neck of the instrument, demand the previous knowledge of a large amount of information relative to the various musical scales with their respective intervals, as well as the musical notes corresponding to each fret and string on the instrument's finger board.

In the usual procedure to assembly a given chord on the instrument's finger board it is necessary, firstly, to know all the musical intervals that make up the chord, determine the musical notes relative to such intervals, and. then, locate each one of these notes on the instrument's finger board, keeping in mind that the assembled chord are phisically feasible of being played, that is, it is possible to be fingered on the instrument's finger board. On the other hand, to identify the chord symbol of a played chord from its respective chord fingering on the instrument's finger board, it is necessary to identify each one of the musical notes corresponding to the string frets fingered and identify the respective intertvals correspondent to these notes. This process becomes more complex than the one described previously for the assembly of chords, especially when the degree "1" or tonic note of the chord under study is not known beforehand, involving a very tiresome procedure of trial-and-error.

To make the procedure decribed above even more complex. it is wortth adding that, for any selected chord, there a re several possible fret and string fingering combinations to be performed on the neck of the instrument, noting that each one of them presents different sound particularities, making it more or less appropriate to the musical context in which it is necessary.

Such difficulties make it in such a way that only experienced musicians a re able to memorize all the information necessary to finger chords on the instrument's finger board or identify a played chord from the finger positions, without going through the procedures of tedious and tiring counsults, which complicates, a lot, the choice of the optimal chord position to be fingered for the musical context.

Along the time, many authors have developed different devices and methods aiming at, specifically or not, to facilitate the laborious task of assembling chords on the instrument 's finger boards.

There were developed several dictionaries of chords, comprising different fret string fingering combinations for each chord. However, due to the enourmous number of fingering combina tions, the dictionaries of chords require a considerable effort of counsulting to choose the more appropriate chord position to the desired musical context. More over, as they do not identify the musical intervals correspondent to each fingered fret string, such dictionaries do not favor the visualization of the interval location on the instrument's finger board and, as a consequence, they do not favor the knowledge for the assembly of chord or for the identification of played chords.

U.S. Pat. No.4,412,473 describes an electronic device capable of indicating in a display, 1,000 to 1,500 different positions of chords for fret stringed instruments, after the imput in the device of the information relative to the tonic note of the chord and its musical intervals, making it a powerful electronic dictionary of chords.

U.S. Pat. No.3, 841, 192 presents a device that aims at the identification of notes and intervals that comprise chords, without attention to the assembly of the referred chords on the instrument's finger board.

Some existing work aim at to display the sequence of intervals corresponding to the various musical scales known in the art, using, for the notation of intervals, the proper notation of the musical scales, therefore not appopriate to the assembly of chords as they do not present the notation of intervals similar to those used in the chord symbol and chord formula and, in this way, not allowing a direct visualization of the possible combination of intervals for chord finqerinqs on the instrument's finger board.

Other authors developed devices that facilitate the identification of the musical note relative to each fret and string in the neck of the intrument, indicating which fret must be fingered for each one of the existing musical scales, without comprising the assembly of the chord itself.

U.S. Pat. No.4,969,383 is an example of the type of device described above. Such device comprises a fixed base and several slide-rules with windows, being each rule specific for an existing musical scale. Through the movement of the slide-rule over the fixed base, the referred windows show the music notes that, must be fingered on the instrument's finger board for the desired musical scale, this device not being adequate for the assembly of chords.

U.S. Pat. No.5, 029, 507, continuation-in-part of U.S. Pat. No. 4,969,383 mentioned above, adds to the referred device a second slide and transparent window, on the top of the first slide-rule, with the indication of some of the musical intervals that comprise the chords. Such indication of intervals, after having being adjusted the position of the slide-rule and the window, appears adjacent to the window of the rule and indicates on the fixed base the respective musical note. This invention has the objective of associating musical scales and chords with the respective musical notes that comprises them, and such notes with the their respective fingering on the instrument's finger board. This way, the visualization of the intervals that comprise the chords on the neck of the intrument is jeopardized by the number of signs that comprise the resulting setting and by the insufficient characterization of the intervals in this type of device.

Pat.No.EP 0080400 describes a device for the assembly of chords where the type of chord and its intervals are specified, one by one, by adjusting five double slide-rules, in association with a 6th rule that is affixed to the device, where the type of chord and intervals used a re indicated in a fixed window. Another window slides over the previous slide-rules until it defines the tonic note of the chord. With the movement of the slide-rules, five sliding planes stay on top of the fixed plane, with windows and geometric simbols. each simbol corresponding to one or more intervals. The last plane moved by the sliding window stays on top of all other planes, with windows corresponding to the instrument's finger board. This way there are 3 to 6 different symbols corresponding to all the intervals that make up the chords. Due to the limitation of the device, symbols referred to intervals other than those relatives to degree "1", degree "3" and degree "5", occupy only half of the space relative to one fret in the representation of the instrument's finger board at the device, some times adjusted to the right, some times to the left of the space relative to one fret. The fingering must, hence, be defined from the resulting disposition of the symbols relative to the intervals, restricted by the few frets diplayed by the slide-rules.

According to the examples above the existing methods and devices in the art for chord assembling on the instrument's finger board, with more or less physical and operational complexity, aim at the identification and positioning of the several musical notes that make up the chords and/or present the final chord fingerings on the instrument's finger board. These methods and devices do not aim at providing a visualization of the disposition of the intervals on the instrument's finger board, with the same notation used in the chord symbol and chord fo rmula.

With this, such methods and devices limit to a great extent, the comprehension and memorization of the law of formation and localization of intervals comprising chords on the instrument's finger board and, consequently. do not favor considerably the capacitation of the assembly of chords for the studious and/or practitioner of this type of instrument, and, mainly, do not facilitate to a great extent the identification of chord fingerings on the instrument's finger board.

As it will be clear from the description of the present invention, the direct visualization of the location of the intervals on the instrument's finger board, with the same notation used in chord symbols and chord formulas, is fundamental for their assembly and identification.

SUMMARY OF THE INVENTION

Surprisingly, it was observed that the procedure of assembly and identification of chords in instruments of the referred type, can be extremely facilitated by the use of a device that allows the direct visualization of the disposition of the musical intervals on the instrument's finger board, with the same notation they present in chord symbols and chord formulas. Such device and respective method of use are hereon presented and claimed.

The present invention is a device for the assembly and identification of chords in fretted stringed instruments such as guitars, electric guitars and the like, through the visualization of the relative and absolute location of musical intervals on the instrument's finger board and their respective methods of utilization.

This invention has as its basic principle, to work directly with intervals that make up the chords, and their location on the instrument's finger board, not necessarily corresponding each interval to its respective musical note during the process of assembly and identification of chords. This way, it is possible to work with much less information, as well as to visualize the law of relative and absolute disposition of intervals on the instrument's finger board, and the law of formation of chords. These laws of formation consisting in powerful tools for the capacity of the practitioner to assembly his own chords and his own fingerings with all the sophistications desired such as, inversion of the bass note, use of open strings, etc...

Therefore, one main object of this invention is to provide the practitioner and/or studious of referred instruments a device and method that facilitate the assembly of chords on the instrument's finger board.

Another object of this invention is to provide the practitioner and/or studious of referred instruments a device and method that facilitate the identification of the chord symbol of a chord formed on the instrument's finger board.

It is a further object of the present invention to provide the practitioner and/or studious of referred instruments a device and method that, facilitate the comprehension and memorization of the law of formation of intervals that make up chords and their location on the instrument's finger board.

These and additional objects and features of the present invention will become more completely apparent from the description and claims bellow, together with the combination of the appended drawings. BRIEF DESCRIPTION OF THE DRAWINGS

Fig.1A is a general plan view of a preferred embodiment example showing the slide-rule over the fixed base, adjusted for a specific chord.

Figs.1B and 1C are plan views of the front and back faces of the slide-rule relative to the embodiment example presented in Fig.1A, showing the intervals relative disposal as they are presented on the finger board of the instrument, for four chord types; Major chords and Minor chords in Fig.1B, and Dominant chords and Diminished chords in Fig.1C.

Fig.2A is a plan view of an optional overlay, preferred transparent, that may be used as an accessory to the embodiment example presented in Fig.1A, for the indication of the musical notes corresponding to each fret and string position on the instrument's finger board.

Fig.2B is a fragmentary plan view of the embodiment example presented in Fig.1A with the optional overlay presented in Fig.2A showing the device in operation.

Figs.3A, 3B, 3C, 3D and 3E a re fragmentary plan views of the embodimnt example presented in Fig.1A, showing examples of chord fingering combinations for assembling the chord "D7(5+) on the neck of the instrument. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

One of the preferred embodiments of the present invention is shown in Figs.1A, 1B and 1C, according to the option for utilization in fretted stringed instruments such as guitars, electric guitars and the like with 6 strings and conventional tuning of strings. This option of embodiment is comprised of a flat slide-rule (1) and a fixed base (2), as shown in Fig.1A. On top of the slide-rule (1) are placed the intervals (9) that constitute the chords, divided in four tables (3), (4), (5) and (6), each table being related to a type or family of chord. The table (3) referring to chords of the "Major" type, together with the table (4) referring to chords of the "Dominant" type are disposed on the frontal face (7) of the slide-rule, as shown in Fig.1A, whereas the table (5), referring to chords of the "Minor" type and the table (6) referring to chords of the "Diminished" type are disposed on the back face (8) of this same slide-rule (1), as shown in Fig.1B. In each table (3), (4), (5), (6) intervals (9) are disposed with the same relative position as they are presented on the finger board of the instrument and are represented by the specific notation of each type of chord, according to the notation usually found in the art. The tables (3), (4), (5), (6) a re formed by six horizontal sequences of intervals, sorted upwards from rigth to left, corresponding each sequence to one string of the instrument, being the superior sequence (10) relative to the 6th string and the other sequences (11), (12). (13), (14) and (15) relative to the 5^th, 4^th, 3^rd, 2^nd and 1st strings, respectively. As shown on table (4) in Fig. 1B, the intervals (16) of "5°" (diminished fifth) and "11+" (sharp eleventh) occupy the same position because they are enarmonics, being the choice of one or another made according to the musical context in which the chord is inserted; the same is valid for the intervals (17) of "5+" (sharp fifth) and "13-" (minor thiteenth).

As shown previously, each fret and string on the instrument's finger board corresponds to one musical note and, at the same time, it may correspond to any interval, depending on the tonic note of the chord under study. Conversely, each interval in tables (3), (4), (5), (6) may correspond to any musical note and, consequently, to any fingering on the instrument's finger board, depending on the tonic note of the chord under study. However, upon defining the tonic note of the chord, the "absolute" positions of all intervals in the referred tables on the instrument's finger board are also defined, and therefore, it is possible to locate them on the instrument's finger board by locating the column of intervals related to the initial fret for each tonic note. Based on this principle, it was determined in the re fer r ed tables the column of intervals corresponding to the initial fret of the neck of the instrument, for each tonic note, by the sequences (18) shown in the Fig.1B and Fig.1C. The sequences (18) are presented according to the international notation, which indicates the type of chord. For example, the vertical column of intervals (19) in table (5). the chord symbol "Dm" (D minor) of sequence (18) corresponds to the position of the initial fret on the neck of the instrument when a chord of "Dm" type is under study. In this case, the vertical columns of intervals, to the left of column (19) of table (5) represent the intervals relative to "Dm" in the same relative and absolute position which they are found on the instrument's finger board. For the sake of simplicity, only chord symbols corresponding to stiarps or "#" chords were employed to represent the present invention, being that, according to the musical context , such chord simbols must be correlated to the respective chord symbols with flats or "b".

By sliding the slide-rule (1) over the fixed base (2). it is possible to get the complete visualization of the position of the intervals on the instrument's finger board for each chord under study. The slide-rule (1) may slide over the fixed base (2) with either face up, depending on the type of chord under study.

Referring now only to Fig.1A, the fixed base (2) presents a sequence of numbers (23) sorted from rigth to left, that indicates the fret position on the neck of the instrument. The fixed base (2) has also two large windows (21) for the observation of intervals which relate to the instrument's finger board and two small windows (22) to indicate chord symbol and tonic note of chord under study. In the example of Fig.1A, the device is adjusted for Major chord types at the top windows and for Dominant chord types at the bottom windows. On such example, the small top window (22) shows "D" (24), indicating that the intervals presented at the top table are related to Major chord types in which the tonic note is "D" (Re). For example, it an be observed in the referred case, that the interval (25) relative to "3M" (major third) appears in several positions: on the 2^nd fret of 1^st and 6th strings, on the 4^th fret of 4^th string, etc. and that the 4th opened string corresponds to the degree "1", and the 1^st opened string corresponds to the interval of a "9" (major ninth).

From the foregoing, it becomes clear the advantages and inventive effect of the present invention. Being the intervals disposed in the same position in which they are on the instrument's finger board and represented with the same notation used in the chord symbols and chord formulas, it is possible, from the simple observation of the device shown in Fig.1A, to obtain an immediate visualization of all possible string and fret fingerings for the assembly of any Major "D" chord type, as well as the correspondent fingerings on the instrument's finger board. Conversely, the identification of the chord symbol of a chord fingering on the instrument's finger board can also be effected by the use of the referred device. The i mmedi a te visualization of the position of the constituent intervals of the chords, as well as the great facility in the transposition of the chord fingerings between the neck of the instrument and the referred device, allows a significant increase in the capacity of assembling and identification of chords, even to the practitioner with less experience, allowing, in this way, a better development of his/her melodic freedom.

As mentioned before, each fret and string position on the instrument's finger board corresponds to just one musical no ta , and, in this way, the correspondence between fret position and musical note is independent of the adjustment of the invention device for a specific chord. This way, the present invention's may be complemented by a fixed indication of the musical notes corresponding to each fret and string position on the instrument's finger board, therefore favoring the advantages of applying the present invention. Fig.2A shows an optional accessot y for the embodiment example presented in Figs.1A, 1B and 1 C constituted by an overlay (26), preferably transparent, with the musical notes (27) corresponding to the fret and string positions on the neck of the instrument. When superimposed to the referred device, as shown in Fig.2B, the overlay ( 26 ) indicates, directly, the musical notes corresponding to the intervals, for each position of the slide-rule (1). For example, according to the position indicated in Fig.2B, it is observed that the musical note "E" (Mi) corresponds to the interval "9 " (major ninth) of a "D" chord, the note "A" (la) corresponds to the interval "5J" (perfect fifth) of a "D" chord and so on. The overlay (26) must be, preferably, adjusted in the fixed base (2) so that it can be optionally removable and do not damage the clear visualization of the disposition of the intervals, which is the main basic: principle of the present invention.

For a better understanding of possible usages of the present invention some examples of applications according to the option of embodiment presented in Figs.1A, 1B and 1C are now shown.

As an exemple of assembling of chord, be the chord relative to the chord symbol D7(5+) (a "D" chord with a minor seventh and a sharp fifth). From knowledge available in the art, it is known that the referred chord is a "Dominant" chord type and its chord formula comprises: "1" (degree 1), "3M" (major third), "5+" (sharp fifth) and "7m" (minor seventh). Adjusting the slide-rule (1), with the "Dominant" table (4) face on top, until the symbol "D7" appears on window (22), according to the position of the device shown in Fig.1A, it is given the disposition of all intervals relative to "D7" chord types, corresponding to the string and fret finger positions on the instrument's finger board. From a simple observation of the referred device, it can be identified, directly, all possible chord fingering combinations for said chord, such as, for example, those shown in Figs.3A, 3B, 3C, 3D and 3E, where the intervals that make up the chord are noted in five possible string and fret fingering combinations, with the indication of the fret position given by the numbers (23) below the fingering combinations.

If the object is to assemble inverted chords, that is, chords with other note than degree "1" on bass, all that is necessary is to, initially, adjust the referred device for the desired chord in the same manner previously described, identify in the said device the interval to be used as the bass and, then, find in the said device a suitable string and fret fingering for the other intervals that make up the chord.

The identification of the chord symbol of a given chord fingering on the instrument's finger board, is made by, initially, adjusting the referred device to the particular chord in the same manner previously described, proceeding the transposition of the chord fingering position to the referred device, at the table of intervals on the slide-rule (1) relative to the type of chord in which the particular chord falls in, keeping the same string and fret finger positions, and, then, by identifying directly in the said device the correspondent intervals that constitute the chord under study, and consequently, the chord formula and the chord symbol. In case the tonic note of the chord to be identified is not known beforehand. it is still possible to identify its chord symbol by superimposing, successively, the chord fingering on the interval tables of the referred device, with the same string and fret finger positions of the instrument's finger board, adjusting the slide-rule (1), until the set of identified intervals in the said device be common, to the chord formula of a given chord known in the art. Proceeding in this way, it may be possible to identify more than one possible chord symbol for the chord fingering. In this case, each chord symbol will be appropriate to a different musical context. Surprisingly and advantageously, the present invention allows also an efficient and fast memorization of the "relative" and "absolute" disposition of the intervals on the finger board of the instrument, for each type of chord and according to the notation employed in the chord symbols and chord formulas, enabling the practitioner a faster assembly and identification of chords.

Other geometric shapes of the embodiment of the present invention may be presented with devices in the shape of tables or in the format of slide-rules with the use of colors and notations to highlight the most important intervals of each type of chord, or else, other forms of presentation of the intervals that are not graphical, as for example, in the form of a video, without departing from the innovative scope of the present invention, once the principle of allowing the visualization of the relative and absolute positions of the intervals on the finger board of the instrument is maintained.

The option of embodiment of the present invention here presented is comprised of table with twenty five vertical columns of intervals, only for the effect of illustration, being that. said tables may have as many columns as desired, without depart of the inventive scope.

It is important to notice clearly that the notation used herein for the intervals is illustrative of a given type of notation used in the art; other notation of intervals available in the art can also be used without loss of the inventive scope.

It is also important that, although the embodiment of the present invention herein presented has been developed with reference to the conventional tuning of strings for instruments of 6 strings, the present invention may be developed according to any other tuning than the conventional one, without causing any depart from the innovative scope of the present invention, once the principle of visualization of the "relative" and "absolute" positions of the intervals on the instrument's finger board is maintained.

It is important that it stays very clear that the present invention may have embodiment in other specific shapes, without depart from its spirit or essential characteristics. The embodiments described herein must be considered, in all respects, only as illustrations and not limitations, and the scope of the invention is, therefore, by the subsequent claims, instead of the preceeding description, All the changes that remain within the meaning and range of equivalence of the claims must be included in the scope.

Claims

1. A device for the assembly and identification of chords on fretted stringed instruments such as guitars, electric guitars and the like, comprising: interval tables (3), (4), (5), (6) for the various types of chords, being said tables made of contiguous and parallel sequences of musical intervals (10), (11), (12), (13), (14), (15), being the number of sequences equal to the number of strings of the referred instrument, being the lines in said tables made by said sequences and the columns of said tables comprised of an interval of each of said sequence, being the ordenation of said intervals in each said sequence made in such way that the resulting relative position between these intervals in said tables is the same relative position they are presented on the finger board of the referred instrument, being the notation used for said intervals in said tables equal to the notation normally used for chord symbols and chord formulas, being each said column of intervals in the said tables identified as an initial fret column for a specific chord and its respective tonic note, being, for each said table and each tonic note under study, the column of intervals corresponding to the opened string notes of the referred instrument, identified as the initial fret column of intervals for said tonic note, and indicated by the chord symbol relative to said tonic note and said table under study, being, for each said table and each tonic note understudy, the position of each said interval with reference to the said initial fret column, equal to the position of this said interval with reference to the initial fret on the finger board of the referred instrument; a slide-rule (1) containing said tables of intervals (3). (4), (5) and (6) and said indicative chord symbols (18) of the said initial fret columns, being the disposition of said tables made in one or both faces of said slide-rule; a fixed base (2) in which said slide-rule slides, being said base comprised by an appropriate groove for the said slide-rule to slide, being the said fixed base provided with windows (21) for the visualization of the interval columns of said tables that correspond to the musical notes on the instrument's finger board for each chord and respective tonic note, being said fixed base provided also with windows {20) for the visualization of the column of intervals corresponding to said initial fret column, being said fixed base provided still with windows (22) for the visualization of said indicative chord symbol of the chord under study, being the said fixed base provided with column numbering (23) corresponding to the fret numbering on the instrument's finger board, being the said column numbering made starting from the said windows (22) for the visualization of the said initial fret columns and being the resulting disposition of the intervals visible through said interval's windows (21) of the said fixed base ordinated in the same way as the disposition of these intervals on the finger board of the referred instruments, for a same chord and its respective tonic note.

2. A device for the assembly and identification of chords in fretted stringed instruments such as guitars, electric guitars and the like, according to the claim 1, wherein said tables of intervals are specific for the chords of the Major type. Dominant type, Minor type and Diminished type.

3. A device for the assembly and identification of chords in fretted stringed instruments such as guitars, electric guitars and the like, according to the claim 1 or 2, wherein the most important intervals of said tables are highligthed as compared to other intervals.

4. A device for the assembly and identification of chords in fretted stringed instruments such as guitars, electric guitars and the like, according to the claim 1 or 2 or 3, wherein the disposition of the intervals in the device corresponds to a string tuning other than the conventional tuning used on the referred instruments.

5. A device for the assembly and identification of chords in fretted stringed instruments such as guitars, electric guitars and the like, according to the claim 1 or 2 or 3 or 4, wherein it comprises an overlay plate (26) indicating the musical notes (27) relative to each position on the finger board of the referred instrument, being said overlay, preferably, transparent, being the positioning of said notes in said overlay made in such a way that, when the said overlay is on top of said fixed base (2), the said notes coincide with the position that they occupy on the finger board of the referred instruments, being said positioning such that it does not jeopardyze the visualization of the intervals of said slide-rule (1), therefore enabling the visualilization of all intevals of said tables through the said overlay with the respective indications of the corresponding musical notes, for each position of the said slide-rule on the said fixed base, being said overlay capable of being easily removed from the set comprised by the said slide-rule and the said fixed base in such a way as to enable a better visualization of the intervals of said tables.

6. A method for the assembly of chords in fretted stringed instruments such as guitars, electric guitars and the like, comprising the following steps: identification of tonic note and type of chord under study; correlation of intervals that make up said chord; adjustment in the relative device of assembly of chords of the slide-rule (1) in the fixed base (2) for the tonic note and the type of said chord; identification on said device of a possible fingering chord comprising all the intervals that make up the said chord and that the said fingering chord be possible to be fingered on the finger board of the referred instrument; transposition of said fingering chord to the finger board of the referred instrument, keeping the same geometry and fret position.

7. A method for the identification of the chord symbol relative to a chord fingering for fretted stringed instruments such as guitars, electric guitars and the like, comprising the following steps: in the case tonic note of given chord fingering is known; adjust the slide-rule (1) on the fixed base (2) in the given device for the identification of chords, for the said tonic note; transpose the said chord fingering to the said device in the window of intervals (21) corresponding to any type of chord, keeping the same geometry and fret position of the finger board on the referred instrument; relate the identfied intervals by the said chord fingering in the said slide-rule and check if this set of intervals corresponds to any chord formula known in the art; if positive, the chord symbol identified associated to the said chord formula and said tonic note identify the said chord; if negative, repeat the two final steps for a window of intervals (21) corresponding to other type of chord until one or more possible chord symbols corresponding to the said chord fingering be identified. In case the tonic note of the given chord fingegering is not known, the following procedure should be taken: transpose the given chord fingering to the said slide-rule separated from the said fixed base in the table of intervals corresponding to any type of chord, keeping the same geometry of the said chord fingering; move the said chord fingering on top of the said slide-rule until the set of intervals identified by said chord fingering in the said slide-rule corresponds to any chord formula known in the art; adjust the said slide-rule in the said fixed base in such a way that the said set of intervals be positioned in the said device in the same correspondent fret positions they are presented on the finger board of the referred instrument; and identify in the device the tonic note of the chord in the window (22) that, associated to the said chord formula, identifies the chord symbol of the said chord fingering; in case it is not possible to identify the said chord symbol in the table of chords initially chosen, proceed identically with another table of chords.