EP1596359A1 - Device and method for automatically tuning a guitar or other stringed instruments - Google Patents

Abstract

A controller (10) and at least one drive for changing the string tension are arranged in the stringed instrument (1) on opposing sides of the strings when viewed in the longitudinal direction of the strings. A bus line is provided between the controller and the drive, so as to span the length of the strings. An independent claim is included for a method of automatically tuning a stringed instrument.

Description

The present invention relates to a device for automatic Voices of a stringed instrument after the generic term of claim 1. It also relates to a method for automatic tuning of a stringed instrument after the The preamble of claim 8.

The tuning of instruments generally requires in addition to one a lot of time, especially from untrained, For example, hobby instrumentalists, must be applied. In the classical method of tuning "by hand" works the musician with a tuning fork, who by hitting sets the desired tone and adjusts by changing the String length or string tension the pitch of the respective String. By repeatedly striking the string and the tuning fork the result is adjusted until the desired one Mood of the string is reached. Based on this mood then the other strings are tuned.

Because partly the strings of the instruments because of one always existing compliance of the material regularly tuned also have to depend on the strings climatic conditions are variable in their length (a guitar string stretches on the stage of a concert hall compared with the heat and humid air the conditions in comparatively dry and cool Exercise room off), a frequent tuning is required. Also after putting on new strings they have to be tuned.

To create a relief here, was in the US 4,803,908 a device for automatic tuning of a String instrument proposed, which has all the features of The preamble of claim 1. In this device are called on a guitar with a "Strummer" there, aids arranged in the body of the guitar all Struck strings at the same time. An electronics detects the Tones, compares them with the target specification and controls one on the strings attacking adjusting device for adjustment the string tensions in such a way that they are the given Sounds hit, on.

The system is very welcome insofar as it is a swift one and allows automatic tuning and so in particular untrained musicians, but also the professionals a high degree decreases in effort. However, the system has a not insignificant Disadvantage. It's overall big and chunky and requires significant changes to the body of the guitar, the on the one hand an influence on their acoustics (sound) and on the other hand on their handling (because of the changed weight) to have. Aside from that, the look of the guitar will also be in not insignificantly changed.

Since the entire guitar the relevant for the sound properties Resonance body forms, also change the Sound properties when it is changed. This is the previously known system in existing instruments almost not retrofittable, but it can also be difficult in new guitars to get integrated. In particular, would be in tonal Regards planning two types of guitars independently to develop a guitar with the previously known Device and one without.

From the described problem, the invention proceeds. It has for its object to provide an improved device so far, which can be integrated into an instrument, in particular a guitar, with minimal influence on the sound properties and with as few and small elements. Furthermore, a method for automatic tuning of a stringed instrument is to be specified, which meets these requirements.

To solve this problem, a device with the features of the protection claim 1 is proposed. A method which achieves this object is specified in claim 10.

Claims 2 to 9 and 11 to 13 contain advantageous Further developments of the device or the method.

The core idea of the invention is the components of the device (which in this sense are also called system can) distribute on the instrument. With a guitar For example, not the entire device is placed in the body. So the head or neck also offers, albeit little, Room, for the (subtle) attachment of other components. In particular, it can be arranged on guitars on the head anyway Means for adjusting the string length or voltage, which is the use of special parts reduced. Overall, in the instrument, For example, the guitar, introduced fewer additional components become.

The signal transmission via the bus line can, for example, via a conventional bus cable, but also wireless, eg. About Radio or infrared, done.

To the separation of the components control and drive however without profound interventions in the instrument body To be able to, are after a development of the invention the control signals between the on an instrument part seated control and the at least one drive preferably guided over the strings serving as bus lines (Claim 2). The strings of stringed instruments are made in many cases of a conductive material (metal) or are wrapped in a thread of one. alternative They can, if the sound permits, with a conductive Be coated material. This solution saves the use other lines laid in the instrument body would have to be. Besides the sound characteristics remains therefore not least the optics of the instrument. In order to, if several strings are to be used as conductors, these are not electrically shorted together, have elements over which the strings are led together (for example, the bridge on a guitar) be designed so that they isolate the strings from each other. These can do this Elements made of a non-conductive material (eg ceramic) manufactured or coated with such, or other precautions of isolation must be made be (for example, interposed insulating discs, etc.).

The drive can be a motor, for example. Electric motor, he but can also work pneumatically or hydraulically.

When the instrument is electrically connected to an amplifier connected instrument is (eg an electric guitar), so can any already existing and to the amplifier connected pickup of the instrument as (part the) registration unit are used.

If, as in a development according to claim 3, the Power supply for the at least one drive over at least one of the strings is led, must on the side of the Drive no own power supply (battery or similar) provided be what an additional component with all negative consequences for the optics and the balance of the instrument and it does not have to be separate Supply line to be laid, leading to the above already would lead to disadvantages.

By a specified as in claim 4 embodiment of Control can do this in a simple way by hitting one Page to be addressed.

An interface as provided according to claim 5 can, gives the possibility, from the outside - also afterwards - to feed software into the device. Furthermore, can via the interface different reference moods in the storage device can be entered to the instrument to be able to vote according to different schemes.

An as proposed in claim 6 embodiment of the device allows a stringwise tuning of the instrument. It can just as well be used as a drive by appropriate gear or similar devices for Adjusting each one string is switchable.

Is the device as defined in claim 7 formed, This results in a particularly compact design. Be the individual Components chosen as small as possible, "disappear" They almost in the overall impression of the instrument and disturb the Musician also not in the game of the same. Besides, it is not required when tuning the instrument external components to call in, the musician can be instrument practical vote everywhere and almost independently.

A development of the device according to claim 8 results a redundant system. The device can also malfunction a string even further to tuning the instrument operated become.

In claim 9 is a preferred embodiment of the device specified for integration in an electric guitar.

The method according to claim 10 provides, as already stated above a solution to the above problem with regard to a It may be preferred with a device are operated according to one of claims 1 to 9, however not limited to such a device.

Claim 11 describes how preferred the strings of the instrument can be used as bus lines. Thereby do not need separate cables or other means of transmission (Radio, infrared) are installed.

A as in a development of the method according to claim 12 required processing of the first digital signal can be useful to reliably from this signal a pitch to be able to determine.

A determination of the fundamental frequency (pitch) of the first digital Signal is preferably carried out with the aid of a mathematical frequency filter (claim 13). This allows in contrast to the otherwise common method of Fast Fourier Transformation (FFT) a faster and more accurate Frequency determination from only one stop of the string.

This is important because with only one stop of the string Overtones necessary for an exact determination of the pitch (frequency) have to be detected, decay very quickly.

Fig. 1

eine schematische Ansicht von vorn einer E-Gitarre als mögliches Anwendungsbeispiel der Erfindung,

Fig. 2

eine schematische Ansicht der E-Gitarre aus Fig. 1 von hinten,

Fig. 3

eine weitere schematische Ansicht der E-Gitarre mit anderen Einzelheiten,

Fig. 4

eine vergrößerte Darstellung des Korpus der E-Gitarre nach der Darstellung in Fig. 3,

Fig. 5

in vier verschiedenen Darstellungen (a) bis (d) einen Reiter des Tremolosystem-Blocks der E-Gitarre,

Fig. 6

schematisch die Befestigung der Saiten im Tremolo-Systemblock sowie deren Kontaktierung mit den Spannungsversorgungs- bzw. Signalleitungen,

Fig. 7

in vier verschiedenen Ansichten (a) bis (d) den Kopf der Gitarre mit daran angebrachten Flügeln und Stellmotoren zum Einstellen der Saitenspannung,

Fig. 8

in vier verschiedenen Ansichten die in dem Kopf der Gitarre sitzenden Flügelt mit den Stellmotoren und

Fig. 9

eine schematische Schaltskizze einer Detektorschaltung zur Ansteuerung einer Tonaderspeisung für die Vorrichtung zum automatischen Stimmen der Gitarre.

In the following, the invention will be briefly described with reference to the accompanying figures. Show it:

Fig. 1

a schematic front view of an electric guitar as a possible application example of the invention,

Fig. 2

a schematic view of the electric guitar of FIG. 1 from behind,

Fig. 3

another schematic view of the electric guitar with other details,

Fig. 4

an enlarged view of the body of the electric guitar as shown in Fig. 3,

Fig. 5

in four different representations (a) to (d) a rider of the tremolo system block of the electric guitar,

Fig. 6

schematically the attachment of the strings in the tremolo system block and their contacting with the voltage supply or signal lines,

Fig. 7

in four different views (a) to (d) the head of the guitar with attached wings and actuators to adjust the string tension,

Fig. 8

in four different views sitting in the head of the guitar wings with the servomotors and

Fig. 9

a schematic circuit diagram of a detector circuit for controlling a Tonaderspeisung for the device for automatic tuning of the guitar.

In the figures, the invention with reference to an embodiment explained in detail on an electric guitar. Same elements are provided in the figures with the same reference numerals. The description based on an electric guitar limits the Invention not. It works just as well on acoustic guitars, e-basses, or other electrical or electro-acoustic or acoustic stringed instruments such as violins, harps etc. are used.

In Figures 1 to 4 is in different, partially enlarged Views an electric guitar 1 shown with a Device according to the invention is provided. The electric guitar 1 can be roughly divided into the body 2, the bridge 3 and the head 4. At the corpus are at the so-called tremolo system block 5 shows the strings 6a-6f with their first ends (Ball ends) attached and side by side on the bridge 3 to stretched to the head 4, where they twirl with their second ends 7 wound and adjustable are set. The Whirls 7 are mechanically connected to wings 8, so that by turning the wing 8 the end of the string on the vortex 7th or can be handled by this. This will the tension or length of the string changed and the guitar voted.

1 also shows a so-called pick-guard 9, which is a kind of cover plate and under the body 2 a space is created in which the electronics of Electric guitar 1 is arranged. Below this pick guards 9 is a control chip associated with the device according to the invention arranged, which is indicated schematically in Fig. 2 with 10 is.

In Fig. 2 it can also be seen that the head 4 of the electric guitar 1 on the mechanics of the wings 8, for example. Via a transmission, attacking servomotors 11 are arranged. The Actuators belong to the device according to the invention and are in later to be described manner with the Control chip 10 connected for control. With the engines can alternatively to the manual over the wing 8 the vortex 7 is rotated and thus the tension of the strings 6a be adjusted to 6f.

In the Fign. 3 and 4 is in another illustration the electric guitar 1 shown. Here are next to those in Fign. 1 and 2 too cognitive elements further details of the electric guitar 1 shown. For example, those on the body 2 below the 6a to 6f sitting pickups (pickups) 12 to recognize which the vibrations of the strings (and thus the through Striking the same generated sound) into an electrical signal convert. These pickups 12 are also used later yet to be explained as part of the invention Contraption.

Furthermore, in these representations, a potentiometer 13 is shown. In general, electric guitars have several such Potentiometer for adjusting the treble, bass and the Volume. Here is the illustrated potentiometer 13 of Volume control. This special controller is for integration the device according to the invention in the electric guitar. 1 not as a conventional potentiometer, but as a so-called push-pull potentiometer, which is an additional Has switching function.

Finally, in these figures, those of the control chip to the tremolo system block 5, more specifically to the strings 6a to detect 6f leading lines 14.

In the Fign. 5 and 6 is the tremolo system block 5 and are respectively on this arranged rider 15 to guide the in the tremolo system block 5 specified strings ends. In Fig. 6 can be seen as the strings 6a to 6f through holes 17 in the tremolo system block 15 and with at their ends arranged thickening (ball ends) 18 at the bottom edge of the holes 17 are held. In the lower one End of the holes 17 is in each case an insulating sleeve 19th used, which at her protruding from the bore 17 Edge is provided with an outwardly facing collar. Between the collar of the sleeves 19 and the thickenings (ball ends) 18 conductive discs 20 are positioned, the Contact thickening (ball ends) 18 of the strings 6a to 6f. These discs are in turn with those on the control chip 10 connected lines 14 (shown here as 14a to 14f) connected.

In this way, the existing of a conductive metal or strings wrapped with a conductive metal thread 6a to 6f of the electric guitar 1 with the control chip 10 electrically connected.

On tremolo system block 5, those shown in FIGS. 5 (a) to 5 (d) shown tab 15 attached. About these are running in the area the 16 designated rider inserts the pages. Of the in Fig. 5 (d) enlarged illustrated rider insert is in the tab shown in Fig. 5 (a) into that shown in Fig. 5 (a). used recess shown right. Since the riders 15 and the riding inserts 16 in an electric guitar 1 regularly made of metal and thus made of a conductive material, need to make a short circuit between over the wires 14 electrically contacted strings to avoid the rider inserts 16, over which the strings 6a to 6f run against each other be isolated. For this purpose, those shown in Fig. 5 (a) Isolated with 21 designated areas.

In Figures 7 (a) to 7 (d) are again details the head 4 of the electric guitar 1 with the components arranged thereon to recognize the device according to the invention, wherein FIG. 7 (d) shows a detail enlargement of D in FIG. 7 (c) represents designated area.

In Figs. 8 (a) to 8 (d), the mechanical units are for adjusting the string tension consisting of the vertebrae 7, the wings 8 and the servo motors 11 once again released represented by the head 4. It can be seen that all these units sit on a common board 22, the Further controls for controlling the servomotors 11 contains. About the metallic and thus conductive vertebrae 7 the strings are electric with corresponding tracks connected to the board 22.

The inventive device for automatic tuning the electric guitar 1 works as follows:

By pulling the push-pull potentiometer 13, the system becomes activated. For this purpose, reference is made to one shown in FIG Circuit used, which will be described below will be.

The control chip 10 can now by striking one of the strings Commands are issued. The by striking the strings generated by the sound pickups 12 in an electric Signal converted, which in the control on a Frequency is converted. In the control are certain preprogrammed commands filed on an within a certain tolerance lying frequency out be called. In this way, for example, the program to tune one of the strings, z. B. the e-string 6f called become. If the program is activated, the control chip loads from a memory a reference frequency for this string, which serves as the target frequency. The string is now optionally struck again, the actual frequency from the through the pickups 12 converted signal in the control chip 10th calculated and on the strings used as bus lines Signal to the board 22 or via this to the appropriate Servo motor 11 for adjusting the string tension to reach the target frequency sent. It monitors the Control chip 10 changes the frequency and gives on reaching the setpoint frequency a stop signal to the servomotor 11. In this way all strings can be tuned one after the other become. As a routine for calculating the actual frequency from the The electrical signal of the pickup becomes a mathematical one Frequency filter used, as this is particularly fast and reliably calculate the frequency.

About an interface not shown in the figures can the control chip 10 different frequency specifications for the strings are given, depending on what kind of mood just to be elected (eg open tuning etc.).

For the transmission of the control signals are only two the strings needed. About two more strings, here the strings 6f (low e-string) and 6e (a-string) will be the power supply for the board 22 and the servomotors 11 in the Head 4 spent, so that its own voltage source there is not needed. The strings 6f and 6e are transmitted the tension chosen, given the low e-string and the a-string the thickest strings of the electric guitar are 1 and so on least tear. Of the remaining four strings 6a to 6 d can each of the control chip 10 any two as Bus lines are controlled freely. That way is the system is redundant and can still work at one or even two torn strings of strings 6a to 6d work.

LEDs on the body 2, for example. In the field of pickups 12 below the strings 6a to 6f can change the state show the control chip 10 and the program flow and so on simplify the handling of the device. Also can here a "quick start" be applied, for. With the ad, by striking which of the strings 6a to 6f in which Sound which commands are called. The assigned to the commands Frequencies can be managed by the control chip 10 so be adapted to the current mood of the electric guitar are, that is, the user always the same string must strike with the same handle to retrieve a command, no matter how the guitar and therefore the string straight is correct.

The power supply of the system takes place in this embodiment externally via the amplifier cable, with the guitar anyway to an amplifier electric connected. The Tonaderschaltung shown in Fig. 9 constantly monitors the internal resistance of the electric guitar 1. This is at normal play ready electric guitar 1 high. Now pulls the musician push-pull potentiometer 13, so couples the pickup 12 from the jack for the Amplifier cable and thus from the amplifier and turns off the Control chip 10 too. This reduces the internal resistance of the electric guitar 1 at least by a factor of 20. This recognizes the Circuit and switches the amplifier cable to one of the Amplifier off so that the electric guitar 1 "muted" tuned can. Furthermore, the circuit switches a supply voltage, which, for example, from the power supply of the amplifier, but even an external power supply can gain on the amplifier cable. This voltage is then supplied to the controller 10 and passed through the strings 6e and 6f in the head 4. Now, the device according to the invention can work. After completion of the vote or, for example, the establishment of the Circuit or the application of new data switches the musician the push-pull potentiometer 13 back to normal position. The internal resistance of the electric guitar 1 rises the now connected again to the amplifier cable pickup 12 again. This recognizes the tone circuit according to Fig. 9 and outputs the signals from the amplifier cable again on the amplifier, the musician can continue playing.

LIST OF REFERENCE NUMBERS

1

electric guitar

2

corpus

3

web

4

head

5

Tremolo system block

6a-f

string

7

whirl

8th

wing

9

Pick Guard

10

control chip

11

servomotor

12

pickup

13

potentiometer

14

management

15

equestrian

16

riders use

17

drilling

18

thickening

19

shell

20

disc

21

area

22

circuit board

Claims (13)

Device for automatically tuning a stringed instrument (1), in particular a guitar, with: a) detection means (12) for detecting a sound generated by striking a string (6a-6f) and outputting a digital signal corresponding to the detected sound, b) memory means for storing predetermined digital signals corresponding to a desired tone, c) a comparison device for comparing the digital signal output by the detection device with a digital signal stored in the memory device and corresponding to the desired tone, d) an adjusting device (7) for changing the tension of the strings (6a-6f), e) at least one drive (11) for driving the adjusting device (7), f) a controller (10) connected to the comparison device which controls the at least one drive (11) via a bus line on the basis of a deviation between the signals representing the generated sound and the desired sound, as determined in the comparison device, characterized in that the control (10) and the at least one drive (11) in the stringed instrument (1) in the longitudinal direction of the strings (6a - 6f) are arranged on opposite sides of the strings (6a - 6f) and that the bus line between the controller (10) and the at least drive the length of the strings is guided bridging. Apparatus according to claim 1, characterized in that the bus line is represented by at least one of the strings (6a-6d) which is made of or wound with a conductive material and / or coated. Apparatus according to claim 2, characterized in that the power supply of the at least one drive (11) is also guided over at least one of the strings (6e, 6f) which consists of a conductive material or is wrapped and / or coated with such a material. Device according to one of the preceding claims, characterized in that the controller (10) is arranged so that it can be switched by the detection device by receiving a digital signal representing a tone within a tolerance range. Device according to one of the preceding claims, characterized in that it has an interface for data exchange. Device according to one of the preceding claims, characterized in that each string (6a - 6f) is assigned an adjusting device (7) with its own drive (11). Device according to one of the preceding claims, characterized in that it is completely integrated in the string instrument (1) with its components detection device, memory device, comparison device, adjusting device (7), drive (11) and control (10). Device according to one of Claims 2 to 7, characterized in that the string (s) (6a - 6f) used as bus line (s) and / or power supply lines are freely selectable by the controller (10), so that at a Defect in a string (6a - 6f) (crack or interruption of the line) from the controller (10) an alternative string (6a - 6f) can be selected as bus or power supply line. Device according to one of the preceding claims, characterized in that it is integrated in a guitar (1), preferably an electric guitar, wherein the controller (10) is arranged on the body (2) of the guitar (1) and the adjusting device (7) and the at least one drive (11) are arranged at the upper end of the neck and the at least one drive (11) via a running along the neck bus, preferably via the bus used as a bus line (6a - 6d), to the controller (10) is connected. Method for automatically tuning a stringed instrument, in which: 1. a string to be tuned is struck, 2. the tone generated by the string is detected by a detection device and converted into a corresponding first digital signal, 3. comparing the first digital signal with a predetermined second digital signal corresponding to a desired tone, and calculating a required change in the string tension from the comparison in a controller;
characterized in that viewed from the longitudinal direction of the string on a first side control a control signal to a connected to a setting device for adjusting the string tension, sitting on the opposite side seen in the longitudinal direction of the string drive via one or more bus line (s) is given. Method according to Claim 10, characterized in that the strings of the stringed instrument consisting of a conductive material or wound and / or coated with it are used as the one or more bus lines. Method according to one of claims 10 or 11, characterized in that the first digital signal is processed for further processing. Method according to Claim 11, characterized in that the frequency of the sound being played back is determined from the first digital signal by means of a mathematical frequency filter and that the second digital signal corresponds to a predetermined frequency.

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