Electrical diagrams show schematically the actual wiring
The wiring diagram in Figure 2 shows how the wiring works, while Figure 3 shows the actual wiring in the guitar and may be more useful when soldering components.
Until now, I have considered the sensor in isolation from everything else. As soon as you connect the sensor to something, a electrical circuit, which changes the characteristics of the sensor. The simplest form of electrical circuit is a sensor directly connected to the output jack (1) and the amplifier on which the volume and tone are controlled. In this electrical circuit, the sound of the pickup is determined only by the resistance of the cord, the input resistance of the amplifier and, above all, the capacitance of the guitar cable.
The volume potentiometer circuit (2,3) is another example of a simple electrical circuit that suits big number guitarists who are frightened by its complexity and distracted from playing by the abundance of all kinds of switches, sensors and their many combinations. A guitar's volume potentiometer allows the player to adjust the volume of the sound without constantly running to the amp. In addition, it also serves to match the guitar output with the amplifier input, which is very sensitive to various kinds of deviations. When the moving contact of the potentiometer is turned to full volume, towards the lobe to which the signal wire of the sensor is soldered, the electric current does not flow through the resistance path of the potentiometer and therefore passes without weakening. When the moving contact of the potentiometer moves to the opposite lobe, which is connected to the common wire, the signal weakens and eventually disappears.
The volume potentiometer also affects the sound of the pickup. Usually, single-coil potentiometers are set to 220k or 250k, and humbuckers are 470k or 500k, but this is also a matter of taste. Volume potentiometers are not exempt from unpleasant side effects, although the moving contact of the potentiometer has a connection (through the resistance of the potentiometer) with the common wire, part of the high frequencies is cut off. This is a typical feature of electric guitars - turning on the volume potentiometer causes the sound to become duller, due to the fact that the height of the resonant peak, which makes the sound bright, in addition to the inductance of the sensor and the capacitance of the cable, is affected by the resistance of the potentiometer.
This high cut problem becomes even more severe when the potentiometer is not connected correctly (4). As the volume decreases, the coil becomes more and more grounded until eventually it is completely connected to the common wire. I think there is no need to explain what happens to the resonant peak.
Output jacks
The standard jack used on electric guitars is 6.35mm (1/4"). Since this type of jack is also used as an input jack on an amplifier, both plugs on the ends of a standard guitar cable are the same, so it doesn't matter which one is included in the guitar, but which one into the amplifier.
Mono sockets have two contacts (1), one of which is connected to the body, the other to the contact blade. When a plug is inserted into a socket, its specially shaped tip comes into contact with the contact tab of the socket, while the other part makes contact with the housing (2). This is clearly visible on open nests. On insulated plastic sockets, the contact located closer to the input is common. Some sockets also have additional contacts that can be used as a switch (4). They are activated when the plug is inserted. Stereo jacks and stereo plugs have an additional third contact (3).
Potentiometer types:
(5)
Standard potentiometer
(6) Stereo potentiometer: two movable contacts on two resistance tracks are moved simultaneously by one slider.
(7) Slider (longitudinal potentiometer): The moving contact moves in a straight line along a resistance track. This type is not used on electric guitars.
(8) Mounting nuts
(9) Potentiometer with a thinner slider.
Circuit design rules
The common wire is the most common element in electrical circuits. An electrical diagram allows you to depict schematically, to make it easier to read, the connections of wires and elements. Elements and in particular the common wire (11) are represented by symbols, and conductors by lines. This ground mapping is especially useful for complex electrical circuits, otherwise the tangle of common conductors will greatly clutter the circuit. In real wiring, all common contacts must be soldered to each other and to the common contact of the socket.
The connection of conductors in the electrical diagram is represented as bold dot (12).
Two wires crossing each other without connection are often represented by two intersecting lines without a point (13), and in American diagrams as in figure (14).
Potentiometers
The volume of the guitar sound (Volume) is adjusted manually using a variable resistor with three terminals called a potentiometer. The two outer terminals are connected to the resistance track, and the middle one is connected to a movable contact, which is moved by a slider along the resistance track, thus changing the resistance. Linear potentiometers change resistance uniformly: for example, when the moving contact is in the middle position, the resistance is equal to half the total resistance of the potentiometer. Audio potentiometers, or logarithmic potentiometers, are a special type of potentiometer in which the change in resistance occurs exponentially. This type of potentiometer is often used for volume and tone control because it gives the impression of a gradual change in volume or tone. Of course, linear potentiometers can also be used, in the end it is a matter of taste. Linear potentiometers are usually designated by the letter B, and logarithmic potentiometers by the letter A (audio). Thus, the 250kV potentiometer is linear, and the 250kA is logarithmic.
The representation of a resistor or potentiometer in an electrical circuit is different. In Germany, the DIN resistor symbol is a small rectangle; The potentiometer is represented by an arrow across the rectangle (DIN - German industrial standard). The American style is more visual, but also more difficult to draw. This book uses a hybrid view.
Capacitors
Capacitors form an obstacle to the direct passage of direct electrical current, but allow alternating current to flow freely. The capacitor consists of two plates separated by a layer of dielectric and placed so close to each other that the alternation of load currents is like alternating current– makes them influence each other. The capacitor's resistance is low at high frequencies and high at low frequencies. In other words, the capacitor allows more high frequencies to pass through than low frequencies. Capacitors are electrical circuit components that can be used as a frequency filter. The higher the rating, the lower the frequencies that the capacitor passes. Low value capacitors can be mica or ceramic. Capacitance is measured in picofarads (pF, pF), nanofarads (nF, nF) or microfarads (μF, mF, ?F). 1nF = 1000pF, and 1000nF = 1 µF (that is, 0.001 µF = 1nF = 1000pF). Unfortunately, the capacitance written on a capacitor is too often misinterpreted. On most of them you will find only numbers, and the sign of the capacity unit will be completely absent. The value of such capacitors can presumably be determined based on their size. In principle, this is not difficult if you have common sense. The number "1000" written on a small capacitor will most likely mean 1000pF (=1 nF). "1E3" would also be 1000pF. And finally ".001", short for 0.001 µF, or 1nF. In addition, some multimeters allow you to measure capacitance.
Another marking is three numbers written on the capacitor, the first two of them indicate the capacitance in picofarads (pF), and the third number is the number of zeros: “503” – 50 pF + three zeros = 50000 pF = 50 nF = 0.050 μF
Switches
Switches are devices that open and close an electrical circuit. by mechanical means. They can also be used to change the direction of a signal. Switches are divided by the number of pins and positions. The simplest type of switch is ON-OF Switch (SPST = two outputs, two positions: on - off, implemented as a toggle switch or button). Figure (1) - designation on the circuit breaker diagram.
ON-ON Switch (SPDT = three pins, two positions: on-on (2), the middle pin is alternately connected to one of the other two. Thus, the signal can be routed in one of two paths.
ON-OF-ON Switch (on-off-on) three outputs, three positions (3), in the middle position no contacts are closed. This switch allows you to connect two capacitors in parallel with the sensor.
An ON-ON-ON Switch is a special type of switch that operates as shown in Figure 4. Three terminals, three positions. In the middle position, all terminals are closed.
A multi-terminal switch allows you to close multiple contacts at the same time. Thus, a double throw (DPDT) switch (5) operates like two SPDT switches (2) placed side by side and activated simultaneously, or three SPDT switches with three terminals activated simultaneously.
If you don't know how a particular switch works, check it with an ohmmeter.
High frequency cut caused by volume potentiometer can be reduced by using a capacitor (1). A suitable container is selected experimentally. Typical capacitor capacity is 0.01uF. Since current always takes the path of least resistance, higher signal frequencies will pass through the capacitor without loss. This - The best way eliminate the problem of RF loss on the potentiometer. For humbuckers connected to a potentiometer with a resistance of 500k, the best option is to use a capacitor with a capacity of 0.001uF and a resistor with a resistance of 150k connected in parallel (2), and a parallel-connected pickup, loaded with a resistance of approximately 300k when connected in this way, produces a sound that is balanced over the entire adjustment range. With single-coils and potentiometers with a resistance of 250k, a capacitor with a capacity of 0.0025uF and a resistor of 220k are used, which allow the sound timbre to be transmitted without changing at low volumes. (I would not recommend using the described tone-compensating chains (Fig. 1 and 2); practice shows that when actively playing with the volume control, they interfere very much)
Capacitors for tone control. (3)
The lower resistance of the potentiometer compared to the capacitor leads to the fact that part of the high frequencies of the guitar signal goes into the ground without reaching the output. Most musicians turn the tone potentiometers to minimum so that the high frequencies are cut off less, preventing the sound from becoming dull. It is recommended to use a logarithmic potentiometer as a tone control (despite the author’s recommendations, the vast majority of manufacturers install linear potentiometers on the tone - maybe they just didn’t read the article ;-)). To control tone, capacitors with capacitances of 0.047 µF or 0.05 µF (47 nF and 50 nF, respectively) for single coils and 0.02 µF (20 nF) for humbuckers are usually used, but of course you can experiment with different capacitances.
If your tone control is a potentiometer with a built-in switch (ON-ON button), you can switch between two capacitors of different capacities (4).
More timbre options can be obtained by using a circular switch (galetnik) with capacitors of different capacities soldered to it and connected in parallel to the sensor (5). This method allows you to change the resonant frequency of the sensor, obtaining a greater variety of sounds. Experimenting with capacitors of various capacities between 0.0005uF (0.5nF or 500pF) and 0.010mF (10nF) will allow you to learn the differences in timbres. A capacitor with a larger capacitance connected in parallel will cut off more high frequencies and make the sound more low-frequency than a capacitor with a smaller capacitance. If the rotary switch clicks when switching, connect a 10M resistor in parallel with each capacitor. You can buy ready-made circular switches with built-in capacitors (6) for most pickups and guitars from German guitar electronics expert Helmut Lemme.
Further experiments may consist of connecting a resistor with a capacitor in series (6-8k) or in parallel (100-150k). This resistor should trim resonance peaks that are too high and make the sound warmer.
humbucker consists of two identical coils, which are usually connected in series, the beginnings of the windings are connected to each other (the so-called midpoint), and the ends form the terminals. One of these leads is often connected to a metal support plate (1), thus providing a shield for the sensor. In this case, you need to know exactly which humbucker pin is connected to the screen. Usually two pins are sufficient, but you can get more sound options if the screen is connected to a separate third pin (2). The maximum amount of freedom for switching coils in a humbucker is provided by five terminals (3) (four wires from the coils (two starts, two ends) plus a ground wire).
You can also turn a humbucker into a single coil by separating its coils with a switch (4). This circuit will give the typical single-coil sound, but of course the noise reduction effect will be lost.
Instead of using a switch, you can include a trip potentiometer (5) in parallel with one of the coils. To make it, open the potentiometer and use a knife to cut a resistance path closer to one of the terminals. At the same time, at the beginning of such a potentiometer, the sensor will operate as a pure humbucker. Then, by turning the potentiometer slider, the moving contact will restore the connection with the other terminal, and towards the end the humbucker will smoothly switch to single-coil mode.
Connecting two humbucker coils in parallel will give new tonal variations while maintaining the noise canceling effect. This is possible via a DPDT (double position) switch (6). This parallel connection will give a brighter sound, but will reduce the output.
Singles
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Manufacturer |
Beginning (first output) |
End (second conclusion) |
Pole/Winding |
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N/clockwise |
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S/clockwise |
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S/clockwise |
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N/clockwise |
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S/clockwise |
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S/CCW |
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S/clockwise |
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N/clockwise |
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Manufacturers and colors of sensor wires
Humbuckers
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Manufacturer |
Adjustable polarity |
Fixed polarity |
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When two single coils with their magnetic poles in opposite directions are used simultaneously, both pickups can be connected in parallel or in series, like a humbucker. Why this connection is not used for pickups on the Jazz Bass like the ones shown above is a mystery to me. Both sensors have the same magnetic polarity, which is very difficult to change because the coils are wound directly onto the magnets.
For sensors that have flat magnets located under the coil, the polarity of the magnetic field can be easily changed by changing the orientation of the magnets.
Determining humbucker coil pinouts
If you do not have a diagram and no assumptions about which coils and which wires come out of the humbucker, you have two ways to determine this commutation: the first is to try to disassemble the sensor (I am against this route, since disassembling the sensor can easily be damaged) , the second is to use an ohmmeter to measure resistance, so that you can then draw logical conclusions from this. Switch the multimeter to resistance measurement mode, set the mode switch to 20 kOhm and measure the resistance on any two wires. If they are not connected, these are wires from different coils. Continue measuring the resistances on the other wires one at a time in relation to one of the first two until the multimeter shows a resistance in the range of 1k to 12k, which means that you have found two wires from one coil. Write down their colors, then use the same method to find the wires of the other coil. When you have found and recorded the colors of the leads of the second coil, only the wire will remain, which should be connected to the copper plate - the screen. Quite often this wire is connected to the braided shield wire of the sensor cable and is therefore easily identifiable.
Determining the Electrical Polarity of Humbucker Coils
To determine the polarity of the coils, connect the wires to a voltmeter and lightly tap the coil cores with a screwdriver. If the voltmeter does not show voltage appearing on one coil, tap the other. Eventually, the voltmeter will show either positive or negative voltage. If the voltage is negative, swap the wires with each other. Now write down the color of the wire that is connected to the + terminal of the voltmeter and in the same way find out the positive contact of the other coil. To obtain the noise reduction effect, both positive terminals are used as sensor terminals, and the negative terminals are connected to each other. In this case, one of the positive terminals of the sensor is connected to ground and the sensor shield. Although this method does not allow one to tell which of the two positive terminals is the beginning and which the end of the coil winding, it does allow common-mode connection if the other sensors are tested in the same way. Such “tests” are absolutely safe - the sensors remain safe and sound.
Determination of magnetic polarity
The magnetic polarity of the sensor cores can be easily determined using a compass. Just bring it to the cores and see which end of the compass needle is attracted to the sensor. If the end is south, then the cores have the north poles at the top of the sensor and vice versa. In principle, if you have a free magnet, you will only need the compass once. Mark the polarity on it using the above method and bring it to the cores. If the magnet is repelled from the cores, they have the same polarity as the side of the magnet that is brought towards the cores.
A pickup switch is required if your guitar has more than one pickup. The SPDT switch shown in diagram (1), although it switches the sensors, will not be able to turn them on at the same time. This can be done using a three-position dual switch (2), resulting in the following options: one first sensor in switch position 1, the first and second sensors together in position 2, and one second sensor in position 3. To avoid differences in the sound volume of the sensors, from - for the use of sensors with different resistances, both sensors must have approximately the same resistance. By using two single coils with opposite magnetic polarity in each coil, a humbucker effect can be achieved by turning the switch to position 2, which places the single coils in series.
Special sensor switches allow you to turn on the first and second sensors either separately from each other or both together. One of these models (3,4,8) is very simple: by moving the switch handle to one side, the contacts on one side close and open on the other, and in the middle position both all contacts are interconnected. These switches also come in L-style (4), made to fit into decks less than 45mm (l3/4") thick. In addition, there are also slide-type switches (7).
Lever type switches with three positions (5) are a little more complex. When you turn on such a switch as shown in Figure 9, it will allow you to implement the following combinations: 1 sensor, 1 and 2 sensors together, 2 sensor.
A two-way, three-way, rotary switch (6) can also be used, but most guitarists prefer regular switches. There are multi-level circular switches (galetniks). Each level consists of a round printed circuit board with pins arranged in a circle and along which a contact strip runs, driven by a switch slide. Other circular switches have 12 contacts in a circle, and vary in the number of positions and contacts that can be closed. Depending on the model, there are 1 x 12, 2x6, 3x4 or 4x3 (the first number is the number of closed contacts, the second is the number of positions). For each level there is a common conclusion in the middle. On some models, the number of switch positions can be changed using a small stop, thus turning a 2 x 6 switch into, for example, a 2 x 3 switch.
With three or more sensors, the number of possible combinations increases and switching becomes more complex. Using three separate ON-OF (SPST) switches is the easiest way to achieve any desired sensor combination (10). However, most guitars with three pickups use a special five-position lever switch (11), which gives the following pickup options: 1, 1+2, 2, 2+3, 3.
More sensor combinations are possible when using biscuits. But since guitarists often prefer five-way lever switches, manufacturers produce special versions of this switch type that give more combinations than usual.
Megaswitch (11), a high-quality lever switch, can be used in place of a conventional five-way switch. In addition to the standard Strat and Tele features (8-pin S or T models), there is also a P-model, which models the pickup combinations of Paul Reed Smith (PRS) guitars, the two humbuckers of which are connected to give the following combinations: 1. bridge humbucker , 2. inner coils of both humbuckers connected in parallel, 3. outer coils of both humbuckers in parallel, 4. outer coils of both humbuckers in series, 5. neck humbucker.
The first such switch was designed to provide five sound combinations from three pickups. For example: single/single/single, humbucker/single/single, humbucker/single/humbucker and humbucker/humbucker. This Schaller switch comes with detailed wiring instructions, so I won't explain them here.
Yamaha's 12-pin, 5-way switch (12) allows for the largest number of different combinations. Its switching, however, is quite complex. This switch can be purchased from Stewart-MacDonald. Because it goes very well detailed instructions connection, I will not repeat it in this book. I would highly recommend this switch if you find the number of combinations available with regular switches to be insufficient.
The tone block is installed on a metal plate. I used this circuit in my last guitar. A capacitor with a capacity of 0.001 uF and a resistor with a resistance of 150k, soldered to the volume potentiometer, should make the adjustment smooth throughout the entire stroke of the regulator.
Antiphase connection of sensors is another opportunity to obtain more timbre options. The effect of this is obtained with at least two sensors with approximately the same characteristics. When two or more transducers are turned on simultaneously, they are usually connected in parallel and in phase, that is, all transducers respond in the same way to the vibration of the strings in their magnetic fields, producing, for example, a positive voltage when the strings approach the transducers and a negative voltage when the strings move away from them . When one or more pickups are switched out of phase, the sound is thin and nasal, but suitable for certain styles of music. This can be easily achieved by changing the connection of one of the sensors. Phase switching is possible ON-ON DPDT (1) switch or potentiometer with built-in DPDT switch. The latter has the advantage because it does not require drilling an additional hole for the switch. If you have two or more humbuckers, you can connect one of them to a switch as shown in Figure 2 to change only its phasing (the humbucker must have a separate ground wire). Two single coils can be connected to a phase switch in the same way as a humbucker.
Phasing when connecting two coils
The table shows the phasing of a typical parallel connection of sensors when they are switched differently by a switch.
N = North Pole, S = South Pole, HC = Noise Reduction
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Winding/Pole |
Clockwise / S |
Clockwise / N |
Counterclockwise / S |
Counterclockwise / N |
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Clockwise / S |
In-phase |
Out of phase |
Out of phase |
Common-mode-HC |
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Clockwise / N |
Out of phase |
In-phase |
Common-mode-HC |
Out of phase |
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Counterclockwise / S |
Out of phase |
Common-mode-HC |
In-phase |
Out of phase |
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Counterclockwise / N |
Common-mode-HC |
Out of phase |
Out of phase |
In-phase |
Diodes
Diode - component electrical circuits, has two terminals (“+” - anode and “-” - cathode), and allows current to pass only in one direction. Diodes can protect the circuit in case the battery is connected incorrectly. If voltage is applied to the terminal of the diode, which is marked with a mark (anode) - basically a line - the diode is properly connected and allows current to flow. If it is the other way around (to the cathode), the diode does not pass current.
Active electronics
Using active electronics instead of passive circuits has several advantages: the guitar's sound becomes independent of the guitar cable and can be adjusted more widely (these advantages become less important if a wireless transmitter with external audio equipment is used with the passive). In addition, the use of an active eliminates the disadvantages of passive circuits, such as muting sound by controls, and expanded switching of signals from sensors becomes possible.
In most cases, an active amplifier is built into the guitar and is powered by a 9-volt battery, which has one drawback - it runs out and needs to be changed, this usually happens at the most inopportune time. Therefore, it is imperative to have a spare battery available. The best decision is to provide for the possibility of switching an asset into a liability and back during the game.
You can also use a 9V battery, while equipping the guitar with a socket for a power supply to recharge the battery.
You can use special plastic containers for the battery. They can be purchased at radio stores or music stores. This container makes battery replacement very easy. Most 9-volt batteries have special terminals for connection.
All active systems must have a switch to disconnect power from the circuit. If you forget to turn off the power, the battery will soon run out. The stereo jack can also be used to turn off the power, since the cable is usually disconnected from the guitar after playing. The negative of the battery should be connected to the middle pin of the stereo socket. If a regular guitar cable with a regular mono plug (1) is inserted into such a socket, the battery negative is connected to the common wire of the circuit, including power. When the guitar is not in use, the electrical circuit must be opened by pulling out the cable.
By using a diode, the circuit can be protected against incorrect battery connection. Diodes allow current to flow in only one direction and only 0.6V of battery voltage is lost on it, so the remaining 8.4V goes to power the circuit. Almost all diodes are suitable for this purpose. 1N4001 and 1N4148 are the two most commonly used diodes for this purpose.
Currently, all active circuits are built on microcircuits - operational amplifiers. Most microcircuits have one operational amplifier and eight pins on board. The first pin on the chip body is often marked with a dot, and the pinout of operational amplifiers such as NE530, TL061, TL071, TL081, LF351, LF411, uA771 and others is standardized. Dual operational amplifier ICs also have eight pins, for example: TL062, TL072, TL082, LF353, LF412, uA772, NE5532, NE5535, AD712. Quad opamps, such as OP11, TL064, TL074, TL084, LF347, uA774 and others, are implemented in a package with 14 contacts.
Analog Devices, Texas Instruments, National Semiconductor are a few names of operational amplifier manufacturers. They all offer different types of amplifiers and with different parameters. For active guitar electronics, low-noise, micro-power opamps are used. The active circuits I'll describe use micropower opamps—models TL061, TL062, and TL064 from Texas Instruments. On the other hand, there are also low noise opamps (such as TL071, TL072 and TL064) that consume more power. All operational amplifiers come with detailed information that describes all their parameters.
If you want to learn more about active electronics, read the relevant literature. My knowledge in this area is mostly general, but I will still try to describe it all in simple words. I would not advise you to design the asset circuits yourself unless you have the appropriate knowledge and equipment, such as a tone generator or an oscilloscope.
If you have no experience in the field of electronics, and you do not understand the circuit, ask some radio engineer or hobbyist you know to make a printed circuit board for you. Most guitar manufacturers do not make active electronics, and leave this opportunity to others. Passive circuits are easier to understand and build.
Installing pickups with active electronics integrated into the guitar is the easiest way to switch to active; They only need a power source, and they are easy to buy. They have an electrical board built into the sensor housing and are manufactured using SMD (surface mount components). The parameters of such sensors are already defined and cannot be changed. They can be connected to volume and tone potentiometers in the usual way, but these potentiometers should not have a resistance greater than 25k, i.e. 1/10 the resistance of a regular guitar passive circuit potentiometer.
Many manufacturers offer ready-made active circuits, the installation of which does not require in-depth knowledge of electronics. They are often implemented in potentiometers or on printed circuit boards. Using the included wiring instructions, you can easily connect the circuit to your guitar. The equalizer allows you to select different cutoff frequencies using a miniature DIP switch.
Voltage follower is the basis of active electronics; it completely eliminates the influence of the guitar cable on the tone of the pickup. The first way to connect to a guitar is to build the circuit directly into the guitar, between the normal passive elements and the output jack. The second method is to install it in an external housing that attaches to a guitar strap and is connected between the output jack and the guitar cable. This method has the advantage that the electronics can be used on another guitar. The absence of any cable capacitance makes the resonant frequency of the sensor very high and the sound is pleasant and bright. By including a capacitor in the circuit (shown as a dotted line in the figure on the left) in parallel with the input, you can return the resonant frequency to its normal level. The capacitance of the capacitor is selected experimentally. The capacitance of standard guitar cables from 500pF to l000pF (lnF) can serve as a guide.
Operational amplifiers in standard 14-pin and 8-pin packages.
All operational amplifiers mentioned in the text correspond to the standard pinout shown in the figure above. Other types may vary, so please be careful.
Operational amplifiers
An operational amplifier, or op amp, is usually implemented as integrated circuit(IC), and is a voltage amplifier. Basically these are small chips with a large number of semiconductors, such as transistors, diodes, etc., which form a complex miniature electrical diagram. Their main advantage is their extremely high input resistance and extremely low output resistance. They can be used for a variety of purposes because their electrical properties are determined by external components such as resistors and capacitors.
Small printed circuit board, shown on the left, is a notch filter made by Helmut Lemme. The Q potentiometer is replaced by a mini switch, which is more practical. From left to right: frequency potentiometer, Q switch, 9V battery connector, input wire, common wire, and output wire that connects to the volume potentiometer.
In the last article, we looked at the general wiring of a humbucker and learned how to solder it according to the circuit of one tone + volume knob + tone knob. Now it’s time to complicate the task a little and add a neck humbucker to the bridge humbucker we already have. Well, it’s natural to switch between them using a three-position switch.
We will create three operating modes:
- bridge humbucker;
- both sensors;
- neck humbucker.
In general, the scheme is very popular nowadays. And I think the information in this article will definitely be useful to you. Let's start with the option with one volume knob for both sounds.
Three position switch
Let's look at the operation of a three-position switch. In guitars they come in two types:
- slider type;
- blade type.
Used primarily in Strat-like guitars. Has 2 pairs of contacts of 4 pieces each. Each pair has its own separate switch. That's why it is called two-pole. To switch between sensors, follow the diagram presented in the figure:
We solder the middle and outer contacts to the volume knob, and connect the wires from the pickups to the switch inputs, as in the figure. Thus, when turning the switch knob to the middle position, both middle contacts will close, only the bridge contact will close to the left position, and only the neck contact will close to the right position.
This type of switch is found on Gibson Les Paul guitars. Schematically, the switch can be represented as follows:
From the picture you can see that the entire switch can be represented as 2 paired on-off switches. In position 1, only contact A is closed, in position 2 both contacts are closed, and in position 3 only contact B is closed. Thus, in the left position the neck sensor will work, in the middle - both, and in the right the bridge sensor. To obtain the required neck bridge positions, simply solder the outputs from the sensors to the required switch pins A and B, and solder pins 1 and 2 to the output jack or to the volume knobs, depending on the version of your circuit.
Wiring diagram for two humbuckers
Below is a diagram of the soldering of pickups with a three-position slide switch, one volume and tone knob. The operating principle is as follows: we immediately send the signal from each sensor to the switch input. Next, from its output we feed the signal to the volume knob through the tone knob. From the volume the signal goes to the jack.
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Now consider a circuit with two volumes and one overall tone. This time we use a lever switch. The operating principle is as follows: we first send the signal from each sensor to its own volume knobs. Next, we connect the output from the volume potentiometers to the switch inputs. Well, we pass the outputs from it through the tone knob and send it to the jack.
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And here are 2 more popular options for desoldering sounds we examined in this article. Once again, I repeat that these are just connection options, demonstrating which I wanted to show the principle of wiring pickups. It all depends on your needs, you have the right to make adjustments.
We are often asked about wiring pickups on different guitars and we have come to the conclusion that many guitarists do not understand how it works and what the difference in sound is. Few people know what serial and parallel wiring of pickups is, what phase switching and coil cutting are. We decided to put things in order by dotting all the “e”s.
Wiring of pickups in a standard Stratocaster
Understanding the very concept of series and parallel circuits can seriously expand your sound range, you will understand how to solder pickups, how to resolder guitar cabinets to a different ohm resistance, and you will also understand how the effects loop in your amplifier works, so you can tune the sound that you want. which you need. This is not a difficult question, but it can be difficult to find direct answers to your questions on the Internet. Let's start with the most popular method of wiring pickups on electric guitars with two or three pickups - parallel wiring.
Think of the parallel circuit as railroad tracks. Each of the rails is independent of each other, just like + and - in an electronic circuit. Plus the earth is sleepers. The output from the pickup is connected to the pickup switch, and the ground is connected to one point (usually back side volume potentiometer). To better understand how this works, take a look at the diagram above.
Sensor wiring by Brian May (Queen)
Brian has three single-coil pickups in series, so his guitar doesn't sound like a Strat. Notice how the current flows through the sensors. Even with the many phase switches on Brian May's guitar, the output of one pickup is connected to the input of another. This is how you connect your effects pedals together. These two methods of wiring pickups give us two various types sound, both of them are quite applicable. No only the right way pickup connections and many guitarists prefer to have both options for maximum versatility. Okay, let's leave the associations and move on to the most interesting thing - the difference in sound. Imagine how a Strat sounds in second position (neck/mid) or fourth position (mid/bridge). You hear the classic twangy sound of a Strat with low noise and low output (Sultans of Swing - good example). The two sensors work as a kind of filter, lowering each other's resistance. This is the essence of parallel wiring and it is what gives you that pure sound - ringing, glassy, elastic and sparkling. This is why Brian May's guitar has nothing in common with a Strat; rather, its pickups sound similar to humbuckers. Pause and listen to the following two examples of guitar sounds with different types pickup wiring. The first example is a Telecaster with a 4-way switch, the second is a Strat with the S-1 system.
A humbucker is a pickup with two reverse-polarity, reverse-wound coils connected in series. Humbuckers sound darker (as in the examples above) + they have more powerful output. However, 4-wire humbuckers can be connected in parallel and produce a single-coil sound that is bright and ringing. Seymour Duncan writes on their website that “a humbucker connected in parallel is 30% quieter than one connected in series.”
A humbucker is a pickup with two coils of reverse polarity and windings.
When connected this way, the pickup will sound similar to 2 single coils placed side by side due to its reverse polarity and winding. Although we don't have an audio example for you, you may be able to find what you need on YouTube, just search for “series parallel humbucker.” I hope we've cleared things up a little bit about why single coils and humbuckers sound different. In addition to the materials from which they are made, different connections of sensors give almost the exact opposite result. Good luck experimenting with your sound!
Last time I described different variants obtaining a different sound using pickups. This time I will describe the modifications of the tone block.
Potentiometers
What is a potentiometer? This is a variable resistor. The electronics are designed in such a way that when we turn down the volume, part of the signal goes to ground, and the rest goes to the amplifier. The origin of the potentiometer does not affect the sound, but their parameters do. And by changing the values of the potentiometers, you can achieve a different sound.
Potentiometers aren't perfect either. And even when they are turned to maximum, part of the signal still goes to ground, which causes losses in power and high frequencies. The losses are not very large, but nevertheless audible. Therefore, the greater the resistance of the potentiometer, the less losses. Potentiometers with a nominal value of 250 kOhms are usually installed on single-coils, and 500 kOhms on humbuckers, since humbuckers sound muddier and the high frequencies there are initially lower than those of single-coils. A brighter sound will be obtained when using 1 MΩ potentiometers.
Keeping the top
However, increasing the potentiometer value does not solve the problem of loss of highs when the guitar's volume is reduced. And the solution to the problem is quite cheap and simple, and is sold in any radio parts store. It is enough just to insert a 0.001 uF capacitor onto two contacts of the volume potentiometer and all the high frequencies will remain in their original form. There is one caveat here - for normal implementation, a logarithmic potentiometer is required. With linear, the volume change will be sharp and stepped. By the way, this is what makes old Fender Telecasters so ringing at any volume level.
Going to the depths
From the previous it is clear that the capacitor conducts high frequencies. Actually, the tone control is a capacitor and a resistor. Typically, guitars are equipped with capacitors with a nominal value of 0.022 or 0.047 uF, but in principle any can be installed. The higher the capacitor value, the more high frequencies will leak into the “ground” and the muddier the sound will be. Although, it doesn’t make sense to set more than 0.1 uF, but you can try.
One of the most interesting devices that was used on some semi-acoustic Gibson ES, including the B.B. King Lucille model and some Blueshawks. Unfortunately, I did not find a single accurate description of the design of this thing, since there is a lot of all kinds of garbage on this topic on the Internet. Even more unfortunately, I haven't been able to play a single guitar with this thing. However, from all sorts of descriptions and videos it is clear that Varitone “cuts off” certain frequencies from the signal. Consists of a position switch and capacitors. First things first.
A simple variton, as it is depicted on the Internet, is an ordinary bunch of capacitors soldered to a positioner. When a position is selected, the signal is sent to a specific capacitor and then to the tone potentiometer. In fact, this gives you the opportunity to choose which capacitor to play through and how deep the timbre will be. A similar thing was implemented in Gretsch guitars in the form of a three-position toggle switch.
More interesting is the design of Gibson's original Varitone. It makes it possible to “cut out” frequencies, radically changing the sound. With such a thing, you don’t need anything else practically, no equalizer or cutoffs - all the sounds are already at your fingertips.
Killswitch
Regular switch. A simple two-position switch or button that turns off the signal completely. It can also be used in music - Buckethead uses this thing all the time.
Built-in booster
Instead of bothering with hot water bottles, why not build a booster into your guitar? There are battery-powered active boosters that will increase the guitar's output and pump up the amp.
Few people know that a booster can also be passive, and that you don’t need to spend a lot of money on it. To get real overload from the guitar itself, you just need to buy two diodes in the store. If they are connected correctly, they will give an overloaded signal, and if you also make adjustments, then no heaters are needed, and you can raise the output signal with one single switch.
It is even sold in stores, although not in ours. It's called Black Ice and consists of several diodes in one small package. By connecting them differently, you can achieve different sounds. But it is too expensive - buying regular diodes is much cheaper.
independence Day
Fans of turning on two pickups simultaneously on guitars with separate volume controls know that if you turn one volume to zero, the sound will disappear completely. However, the problem can be solved by simply rearranging the wires on the potentiometer, as in the diagram. After this, when turning the volume to zero, only a specific sensor will be turned off. Honestly, I don't know what the magic is, but it works.
True, there is also by-effect. The fact is that with such a connection, two sensors will always work, but at an extremely minimal volume - such that the second sensor will not even be heard.
Active electronics: equalizers, preamps, etc.
Nanotechnology allows you to build into the guitar any electronic crap that the user wants. The entire pedalboard can thus fit into the body of one guitar, but is it really necessary?
Using just two pickups on your electric guitar, using their combinations you can get different sound without buying additional devices. The usual way to arrange sensors is in parallel or in phase. For sensors whose wires are sealed in the housing and are not solderable, changing the sensor combination can be difficult.
In any case, the right pair of pickups wired in parallel and in phase produces most of the rock or jazz sound. The standard pickup combination on the Strat produces a distinctive funky sound.
To get the sound you want, it will take a little time and patience to find the combination of pickups. First you need to place the pickups inside the guitar, and then change the combination of wires to achieve a change in sound. After you have found the desired combination, you need to figure out how you can quickly and conveniently switch between the standard combination and the one you have chosen. It is recommended to use no more than two switches in order to quickly change the sound. The easier way is to stick to traditional combinations that are guaranteed to give good results.
In order to understand how to position the pickups, you need to understand a little how humbuckers work. A humbucker pickup has two coils side by side. Each of these coils receives string vibrations, but at the same time introduces its own noise interference. Even though humbuckers are less noisy than single-coil pickups, there is still noise. Alternatively, to minimize noise, the humbuckers were covered with a metal cover; almost all vintage pickups were like this. There are also pickups without covers, both humbuckers and single coils. I don’t know how effective it is to cover sensors with covers, I can only say that sensors with covers sound more muffled (blues-like), less aggressive. Therefore, if you are a fan of aggressive music, then it is better to choose sensors without covers; on them you will get the maximum signal that can be used in the effects chain.
The figure above (two on the right) shows the connection of sensors in phase and antiphase. Signals in phase will reinforce each other, while signals in antiphase will be suppressed. The operating principle of an ordinary humbucker is based on the antiphase connection of two identical coils located at different poles of the magnet. The useful signal from the strings in the coils is added, and interference noise (independent of the magnets) is subtracted. Logically, when two sensors are turned on in antiphase, we should not hear anything at all, but the string, in addition to the general vibration (fundamental tone), also makes a bunch of small multidirectional vibrations (overtones-harmonics), formed by dividing the sounding string into equal segments. The following situation emerges: at different points the string moves in different directions and at different speeds. Accordingly, the currents in different sensors will differ slightly from each other. And the closer the frequency component (harmonic) is to the fundamental tone, the more likely it is to be suppressed by a signal from a sensor switched in antiphase. In general, we will hear the fundamental tone approximately 2 times quieter than with simultaneous in-phase (in-phase) switching on, and the higher the order number of the harmonic, the louder (relative to the already quiet fundamental tone in comparison with conventional switching on), its share in the spectrum of the main signal will be. As a result, we will get a quiet sound, rich in harmonics, and the sound will be higher, but it will have a different character. Typically, both humbucker coils are wound in one direction, then connected to each other by the internal terminals of the windings (the beginning of one with the beginning of the other). the remaining external pins go to ground, it will be " cold", the second wire will be the output, " hot". The result is a counter-series connection of the coils, for noise they will be in antiphase, the background will be suppressed (subtracted). Of course, it will not be subtracted completely, but significantly, and for a signal from the strings - in phase, so the voltages from both coils will be added. This will happen if each coil has magnets in different polarities. For example, if in one coil it is “north” to the strings, then in the other coil it is “south” to the strings. Or between the magnetic cores of different coils there will be one magnet touching the magnetic cores of different coils with its different poles.
Let's try to look at several options for connecting sensors in more detail using diagrams.
Gibson uses a neck/both/bridge pickup combination as standard and is easy to implement. But, using additional switches, you can also use humbuckers with output from only one of the coils. An example diagram is below.
Single coil + humbucker
They are in phase. The circuit is very simple, it allows you to use either 4 pickup coils together or each individually. In this case, the sound will be very different; it is desirable that the resistance of both humbuckers coincide.
routing humbuckers individually
Single sensors
The diagram below shows how to make the wiring for singles, as a result of which it will be possible to use each single sensor separately or together.
Below are a few more circuits that allow you to use humbuckers and single coil pickups in various combinations. You need to understand that the selection of the combination you need and, accordingly, the sound should depend entirely on your decision, and the more wiring options you try, the greater the chance that your pickups and guitar will sound the way you need.