Device for tuning musical instruments name. Musical instrument tuning device
MEASURING EQUIPMENT
A. Grekov
DEVICE FOR TUNING MUSICAL INSTRUMENTS
Tuning musical instruments, as is known, is a difficult and painstaking task. Sometimes a lot of time is spent on this. But it can be greatly simplified if you use special devices. of these, developed by G. Markosov from Kislovodsk, is described below. It allows you to tune in everyday life any musical instrument whose structure is based on the principle of equal temperament, such as, for example, a piano, button accordion, or harp.
The device provides high tuning accuracy, allows you to expand and contract intervals in any part of the range, and adjust the instrument “on tap”. Tuning can be done visually, as well as using the unison-octave principle.
The operating principle of the device using the visual tuning method is based on comparing the height of the reference semitone with the height of the instrument's semitone. The comparison takes place on a cathode ray tube. In this case, the so-called circular scan is used, which is widely used in various fields of radio electronics.
In Fig. Figure 1 shows a block diagram of the device. It consists of a semitone generator G1, a limiting amplifier A1, a frequency divider D1, an amplifier A2, a phase shifter A3, a sensor E1, a signal amplifier A3 from the sensor, a mark former A4 and a cathode ray tube HI.
Switch S1 changes the frequency of the signal generated by node G1 and the conversion factor of the divider D1. Switch 52 selects the octave by connecting the input of amplifier A2 with the corresponding outputs of divider D1. Depending on the method used to tune the musical instrument - visual or auditory, the signal through switch S3 comes from the sensor to amplifier A3 (visual tuning) or from amplifier A2 to the sensor (auditory tuning). Switch S4 allows you to cover amplifier A3 with positive feedback, in which quartz resonator Z1 is turned on. In this case, the amplifier is disconnected from the E1 sensor and turns into a calibration generator.
Rice. 1. a device for tuning musical instruments
With the visual tuning method, electrical vibrations with a frequency corresponding to the selected semitone, amplified by node A2, arrive at the deflecting plates of the cathode ray tube HI. The electronic one will draw or an ellipse on its screen. Since the frequency of the applied signal is relatively high, the movement of the beam is imperceptible.
The signal from the sensor, the frequency of which corresponds to the pitch of the sound, is amplified in node A2. A4 forms short rectangular pulses from it - marks, which are fed to cathode ray tubes. These marks look like luminous dots on a circle (ellipse).
If the frequencies of the reference signal and the signal from the dates are equal, then the marks will be motionless. Otherwise, they will begin to rotate in one direction or another. The degree of detuning of the instrument can be judged by the speed of movement of the marks.
The schematic diagram of the exemplary -luton generator and frequency divider is shown in Fig. 2.
The generator is assembled on transistor VI. Thanks to deep feedback on direct and alternating current (through resistor R2), high quality factor of the coil, the use of KSO-G mica capacitors with high thermal stability of parameters, weak coupling of the generator with subsequent nodes, stability of the generated frequency is achieved. This is also facilitated by periodic frequency correction using a quartz oscillator built into the device. The fundamental frequency produced by the generator is 3520 Hz, which corresponds to the semitone A. If necessary, the generated frequency is adjusted with variable resistor R4. They also overestimate or underestimate, which is necessary, for example, when tuning a musical instrument “on tap”.
To obtain another 11 semitones, the SI switch changes the generated frequency and divides it accordingly using a divider made on D-flip-flops Dl. l, D1.2, D2.1, D2.2, D3.1, D3.2. The conversion factor of the divisor changes depending on what needs to be obtained. In table Table 1 shows the values of the generator frequency, divider conversion factors and signal purity at the divider output.
The generator is connected to the divider through a buffer amplifier made on transistor V2, connected according to the source follower circuit.
Trimmer resistors RI2 - R14 equalize the size of the figure image on the oscilloscope tube at different octaves. The required “forward” image is set with a variable resistor R15.
Rice. 2. Schematic diagram of the genepatorus of reference pulses and frequency divider
By shifting the variable resistor R15 through the capacitor C17, the signal is sent to a two-stage amplifier assembled on transistors V3 - V5 (Fig. 3). The second cascade is made according to a push-pull circuit and operates in AB2 mode. The circuits formed by the primary winding of transformer T1 and capacitors C.19 - C2I, the primary winding of transformer 72 and capacitors C22 - C24 separate the first harmonic from the rectangular voltage.
From the output of the amplifier, the signal through phase-shifting chains R22C25 and C28R23 is fed to the deflecting plates of the cathode ray tube Ш. From the secondary winding of transformer T2, a low-frequency non-inverted signal is supplied to connector XI, to which a sensor is connected when tuning the instrument using the unison-octave method.
An amplifier for the signal coming from the sensor is assembled on transistors V6 - V8 (connected to connector XI). V9 generates short rectangular pulses, the duration of which is determined by the time constant of the differentiating chain C35R37. These pulses are fed through C36 to the cathode ray tube modulator. At the same time, bright marks are displayed on its screen in “orbit”.
The device does not have a separate quartz oscillator used to correct the frequency of the emperor of exemplary semitones. It is performed by the first two stages of the signal amplifier from the sensor. In the correction mode, the cascades on transistors V6, V7 are covered by positive feedback, in the circuit of which the quartz resonator Z1 is connected. Its own resonant must be a multiple of the semitone frequency, since it is at this frequency that the correction is carried out. The device uses a quartz resonator with a frequency of 8800 Hz. Therefore, when correcting the frequency, 20 me-currents will be displayed on the first octave in the “orbit”, and 40 on the small octave.
To tune musical instruments, two sensors are used: acoustic type DEM-4 and magnetoelectric. The latter is made on the basis of the DEMSh-Im capsule. In the winding of the sensor (magnetoelectric), when the string oscillates near the pole pieces, voltages arise, which are transmitted to the device. When tuning is carried out by meto-electromechanical resonance, on the contrary, vibrations coming from the device to the sensor excite the string.
Acoustic is also reversible. It can be used both as a sound vibration emitter and a microphone.
The device is powered from an AC mains voltage of 220 V. It consumes about 10 W. All amplifiers are powered by a 22 V rectifier. A stabilized voltage of 9 V is supplied to transistors VI, V2 and microcircuits. Power to the anode cathode ray tubes (700 V) comes from a rectifier using diodes V9, V10, assembled according to a voltage doubler circuit.
The device is mounted in a housing measuring 215 X 195 X 100 mm.
Today's application will be useful to every musician. If you have ever been interested in playing stringed instruments, then you have probably heard about such a device as a tuner. A tuner is a box with a pointer or display that helps you fine-tune the instrument. A guitar, for example.
If you are the happy owner of an Android phone, then you can easily get a tuner in your mobile. The gStrings app will help you tune your guitar (or whatever strings you have) anywhere, anytime.
The main interface operates in three modes:
- The sound of a note. Select the desired note and hear a characteristic sinusoidal sound
- Tuning a specific note. You pull the string, and the arrow on the screen will show the deviation from the desired frequency
- Autotune. The program automatically detects the nearest note and shows the deviation from it. This is how most tuners work
In addition to several color schemes, there are also a number of settings. This is adjusting the microphone volume and selecting an instrument for tuning: violin, viola, cello, double bass and, in fact, guitar.
There is one more feature that may be useful to professionals. Imagine that the tuning in the band or orchestra you are playing in is slightly out of whack. For example, instead of 440 Hertz for the note "A", the instruments are tuned to 460 Hertz. In this case, gStrings will also help you.
The invention relates to the design of a device for tuning musical instruments. A device for tuning stringed musical instruments contains a phonogram with twelve sound tracks, rotating on a seven-speed pulley. In this case, each pulley stage is made with given dimensions and rotates at a given speed. The device contains a motor that imparts rotation to the pulley using a drive belt put on a pulley stage and moved from one pulley stage to another, and an adapter with a light bulb located above the phonogram with the ability to move relative to it. In this case, the signal from the adapter is sent to a photocell installed under the phonogram, and through a low-frequency amplifier it is transmitted to the device’s speaker. The technical result achieved in this case is to increase the accuracy of tuning a musical instrument. 3 ill.
The claimed invention relates to a device for tuning musical instruments and is used for precise tuning of all types of stringed musical instruments. The device has exceptionally high tuning accuracy and produces 72 precisely tuned musical sounds. Currently, musical instruments are tuned using a tuning fork, and only one string is precisely tuned, and the remaining eleven strings of other octaves are tuned by ear. At the same time, even the most experienced tuners make large errors, and a poorly tuned musical instrument irritates the ear and distorts the beauty and content of a musical work.
A reed tuning fork is known for tuning musical instruments (see SU 153169 A1, class G10G 7/02, publ. 01/01/1963), made in the form of a round body bearing on the surface the musical notations of musical tones, and containing a voice bar with several reeds, a mouthpiece and an adjustment dial for switching to a certain tone or musical intervals, while the reeds are located along the chords of the circumference of the voice bar, and the adjustment disc is made in the shape of a truncated cone that interacts with the beveled edges of the body opening.
The known tuning fork does not allow achieving high precision tuning of a musical instrument.
The technical problem to be solved by the claimed invention is the development of a device for tuning stringed musical instruments, which allows achieving high tuning accuracy.
The problem is solved by using a device for tuning stringed musical instruments, containing a phonogram with twelve sound tracks, consisting of six octaves and rotating on a seven-speed pulley, each of the steps of which is made with given dimensions and rotates at a given speed, a motor that gives rotation to the pulley using a drive belt put on a pulley stage and moved during operation of the device from one pulley stage to another, an adapter with a light bulb located above the phonogram with the ability to move relative to it, while the signal from the adapter is sent to a photocell installed under the phonogram and through a low-frequency amplifier transmitted to the device speaker.
The diagram of the device is shown in Fig. 1 (side view) and Fig. 2 (top view). Musical sounds are extracted from a phonogram with twelve audio tracks, consisting of six octaves (72 sounds in total).
Figure 3 shows a phonogram made on X-ray film. The phonogram 3 rotates on a seven-speed pulley 1 and has seven steps with strictly defined dimensions and strictly defined rotation speeds. The pulley rotates from a synchronous motor 4. A belt drive 8 goes to the pulley stages. The accuracy of the adjustment of the entire device depends on the motor driving the pulley. The pulleys are ground with a rotating motor to the required dimensions. In this case, the diameters of the phonogram pulleys are 21, 21-22, 47-23, 81-25, 23-26, 73-28, 32-30 mm. All pulleys are manufactured with an accuracy of +0.01 mm. Above the phonogram there is an adapter 5 with a light bulb from a flashlight 6. Under the phonogram, the adapter has a photocell 7 installed. When the device is operating, pulsating light falls on the photocell through the rotating phonogram, the resulting signals are amplified by a low frequency amplifier (LF) and enter the speaker. The ULF is used two-channel, two-contact, with a power of up to 10 watts. In this case, a foot pedal is connected in series to the wires going to the ULF to control the volume.
The drive belt from the motor drive pulley is located on the thickest 30 mm pulley of the seven-speed pulley 1. The motor and the light bulb located above the first four-character audio track are turned on, while the soundtrack rotates at a speed of 16.33 rps. To determine the frequency of the sounds produced, the number of revolutions is multiplied by the number of characters in the audio track, and we get 4 × 16.33 = 65.4 Hz. This frequency corresponds to the sound of the C major octave. Next, we move the light bulb to the next track of the phonogram, which also has 6 characters. Accordingly, we get 6×16.33=98 Hz. This frequency corresponds to the sound Sol of the same octave. Then we move the adapter to the next tracks and get the same sounds for the other octaves Do and Sol. The most recent track has 192 characters. It corresponds to a frequency of 192×16.33=3136 Hz, corresponding to the sound Sol of the fourth octave.
Under the sounds of the C and G signals, we tune the strings of all seven octaves and then move the drive belt to the next pulley stage with a diameter of 28.32 mm. Now the soundtrack rotates at a speed of 17.3 rps. We make the same calculations, multiplying the speed of rotation of the phonogram by the number of characters on the audio track, and we get the sounds Do# and Sol#. We tune these strings of all octaves, each time moving the motor, secure it with a screw and move the belt to other steps of the pulley.
To find out whether the string of the instrument being tested is accurately tuned, a guitar pickup is installed at a close distance to the string to determine the accuracy of tuning. A microammeter is connected to it through diodes. The maximum deflection of the instrument needle determines the quality of tuning of your instrument. Even if a person does not have absolute pitch, with the help of such a device it will be possible for him to tune any stringed musical instrument with an accuracy of 0.6%. The error in tuning “by ear” even by the most highly qualified tuner is at least 3-5%.
A device for tuning stringed musical instruments, containing a phonogram with twelve sound tracks, rotating on a seven-speed pulley, each of the stages of which is made with given dimensions and rotates at a given speed, a motor that gives rotation to the pulley using a drive belt, put on the pulley stage and moved with one stage of the pulley to another, an adapter with a light bulb located above the phonogram with the ability to move relative to it, while the signal from the adapter is supplied to a photocell installed under the phonogram and transmitted through a low-frequency amplifier to the speaker of the device.
The sound of a tuning fork helps to tune musical instruments, which allows you to play them correctly. You can, of course, rely on your own hearing, but it would be safer to double-check.
About musical instruments
People have had a need for creativity for a very long time. This is how the first musical instruments began to appear. Of course, at first they were extremely primitive, but over time they became more complex. And at some point it turned out that for convenience they need to be brought to a certain standard, especially if they have different designs. Thus the need for a universal reference point arose. Knowing one note, you can arrange the rest, but where can you get it from? In search of a solution to this problem, a device was invented, which is sometimes also classified as a musical instrument. You can't do without it if you need to tune a piano or grand piano, so it's not easy to find a replacement.
What is a tuning fork?
Those who have a piano at home sometimes call a tuner to make sure the instrument is not out of tune. And then you can see a strange curved stick in the hands of the master. In fact, this device may look different, but its purpose is always the same. A tuning fork is a device that produces the note “A” of the first octave. Based on you, you can line up all the other notes.
Each musical instrument has its own characteristics and operating principle. There are also factors that interfere with proper functioning - for brass winds and strings this could be careless movement, sudden temperature changes, etc. Therefore, a tuning fork is an indispensable thing for every musician, which allows you to quickly put everything in order. It is not surprising that it was invented, because it was needed so badly. This gave impetus to the development of ideas for performing the same works with a large variety of musical instruments, because now it was not difficult to harmonize their sound.
By the way, “tuning fork” is a German word, although it doesn’t mean exactly that. It translates as “room sound”, and the musical instrument in question is called Stimmgabel in Germany.
History of appearance and development
The tuning fork was first invented by the English court musician John Shore. He was a trumpet player and apparently had a good understanding of the laws of physics, particularly acoustics. plate for the note "A" at that moment was 119.9 Hertz. This is how the tuning fork appeared. Photos of old specimens are very interesting, because today you rarely see such a device in life. It looked like a two-pronged metal fork that had to be struck against something to make a sound.
Over time, the appearance of the tuning fork changed, and varieties appeared with a wooden box that acts as a resonator. In addition, the oscillation frequency of the device gradually increased. Today, for the note “A” of the first octave, it is 440 Hertz.
Modern varieties
Today, musicians have a huge variety of tuning forks to choose from. They can be made in the form of a metal fork, pipe or whistle. They can also make sounds of different pitches, the most popular being “la”, “mi” and “do”. Sometimes it’s even several tones at a time - such devices are often used by guitarists and violinists, since the classical tuning for each of these instruments is the same.
In addition, in recent years, a large number of electronic tuning forks, called tuners, and applications and websites on this topic have appeared. So it is difficult for a modern musician to fail to tune his musical instrument - there will always be the opportunity to start from the fundamental tone. By the way, a tuning fork is a serious help for the choir, especially if singing occurs without music - Singers in this case focus on the sound of a standard tone, but do not forget about the compatibility of their voices.
For each specific purpose there is a tuning fork. For a guitar it can contain all six notes for open strings, for violin and cello - four, etc. This greatly simplifies the tuning process. But no matter what it looks like and what it is intended for, in any case, the tuning fork works in accordance with the laws of physics.
Principle of operation
Probably most of the school physics course remembers that sounds are caused by vibrations. And this case, of course, is no exception. A tuning fork for a guitar, piano or any other instrument works on the same principle - some action sets the plate in motion. It, in turn, vibrates and produces a tone of one pitch or another. The device creates harmonic waves, which means that the resulting tuning fork sound is very clear. In addition, it is not affected by ambient temperature.
By the way, most tuning forks are quite compact, and there is also a physical reason for this. The fact is that the larger it is, the lower the sound it produces, even if other parameters are the same.
Special types
There is one more type of tuning fork, which is important not to be confused with the others, since they are used in completely different cases. We are talking about a medical tuning fork, which is needed by otolaryngologists, orthopedists and neurologists to study the characteristics of sound conduction through the patient’s bones.
This device also serves to determine the response to vibration. It can be used to identify diseases such as pallisthesia or polyneuropathy, which occurs, for example, in diabetes mellitus. This device is called a tuning fork not only for its similar appearance, but also, of course, for a similar operating principle.
In a figurative sense, this word is also used, for example, by psychologists. They sometimes suggest that their patients find an “inner tuning fork,” that is, a core, a support, the foundation of their personality.
In symphony orchestras, where the number of different musical instruments is simply enormous, the tuning fork is not such a frequent guest. Usually the tuning occurs in accordance with the oboe - almost nothing affects its sound. However, if a piano is used in a performance, it must first be tuned in accordance with
a tuning fork, and the rest of the instruments are adjusted using it. Even if some mistake occurs, the entire orchestra will sound harmonious, and perhaps the audience will not even notice the flaw.
Guitar tuning
This musical instrument remains extremely common among those who do not perform professionally. Of course, this is a classical one. When it is new or has recently had its strings replaced, it has to be tuned often. And later, after careless movement and as a result of temperature changes, correction of its sound may be necessary.
If you have a special tuning fork for guitar at hand, the task is greatly simplified, because each note produced corresponds to a separate string. But if you only have the classic variety at your disposal, you will have to work a little and strain your hearing. The sound produced by the tuning fork should match the tone of the first string held at the fifth fret. Once this is achieved, you can continue. To do this, each subsequent string is clamped at the fifth fret and tuned in unison with the previous one. It's not difficult, but it takes some practice. The only exception is the third, for which the third fret is used.
By the way, if the guitarist does not have a tuning fork at his disposal, then you can listen to ordinary telephone beeps, they also correspond to the note “A”. You can also adjust the strings of a violin, cello and similar instruments yourself. Well, tuning a piano or grand piano is so complicated that it is better to entrust this task to professionals.
