Structurally, any color and music (light and music) installation consists of three elements. Control unit, power amplification unit and optical output device.
As an output optical device, you can use garlands, you can design it in the form of a screen (classic version) or use electric directional lamps - spotlights, headlights.
That is, any means are suitable that allow you to create a certain set of colorful lighting effects.
The power amplification unit is an amplifier(s) using transistors with thyristor regulators at the output. The voltage and power of the light sources of the output optical device depend on the parameters of the elements used in it.
The control unit controls the intensity of light and the alternation of colors. In difficult special installations designed to decorate the stage during various types shows - circus, theater and variety performances, this block is controlled manually.
Accordingly, the participation of at least one, and at most, a group of lighting operators is required.
If the control unit is controlled directly by music and works according to any given program, then the color and music installation is considered automatic.
It is precisely this kind of “color music” that novice designers - radio amateurs - have usually assembled with their own hands over the past 50 years.
The simplest (and most popular) “color music” circuit using KU202N thyristors.
This is the simplest and perhaps the most popular scheme for a color and music console based on thyristors.
Thirty years ago I first saw a full-fledged, working “light music” up close. My classmate put it together with the help of my older brother. It was exactly this scheme. Its undoubted advantage is its simplicity, with a fairly clear separation of the operating modes of all three channels. Lamps do not flash simultaneously, red channel low frequencies blinks steadily in rhythm with the drums, the middle green one responds in the range of the human voice, the high frequency blue one reacts to everything else subtle - ringing and squeaking.
There is only one drawback - a 1-2 watt pre-amplifier is required. My friend had to turn his “Electronics” almost “fully” in order to achieve a sufficiently stable device operation. A step-down transformer from a radio point was used as an input transformer. Instead, you can use any small-sized step-down network trans. For example, from 220 to 12 volts. You just need to connect it the other way around - with a low-voltage winding to the amplifier input. Any resistors, with a power of 0.5 watts. Capacitors are also any, instead of KU202N thyristors you can take KU202M.
"Color music" circuit using KU202N thyristors, with active frequency filters and a current amplifier.
The circuit is designed to operate from a linear audio output (the brightness of the lamps does not depend on the volume level).
Let's take a closer look at how it works.
The audio signal is supplied from the linear output to the primary winding of the isolation transformer. From the secondary winding of the transformer, the signal is supplied to active filters, through resistors R1, R2, R3 regulating its level.
Separate adjustment is necessary to configure the high-quality operation of the device by equalizing the brightness level of each of the three channels.
Using filters, signals are divided by frequency into three channels. According to the first goes to the channel the lowest frequency component of the signal - the filter cuts off all frequencies above 800 Hz. The filter is adjusted using trimming resistor R9. The values of capacitors C2 and C4 in the diagram are indicated as 1 µF, but as practice has shown, their capacity should be increased to at least 5 µF.
The filter of the second channel is set to medium frequency - from approximately 500 to 2000 Hz. The filter is adjusted using trimming resistor R15. The values of capacitors C5 and C7 in the diagram are indicated as 0.015 μF, but their capacity should be increased to 0.33 - 0.47 μF.
The third, high-frequency channel carries everything above 1500 (up to 5000) Hz. The filter is adjusted using trimming resistor R22. The values of capacitors C8 and C10 in the circuit are indicated as 1000 pF, but their capacitance should be increased to 0.01 μF.
Next, the signals of each channel are individually detected (germanium transistors of the D9 series are used), amplified and fed to the final stage.
The final stage is performed on powerful transistors, or on thyristors. In this case, these are KU202N thyristors.
Next comes optical device, the design and appearance of which depend on the imagination of the designer, and the filling (lamps, LEDs) - on the operating voltage and maximum power output stage.
In our case, these are 220V, 60W incandescent lamps (if you install thyristors on radiators - up to 10 pcs per channel).
The order of assembling the circuit.
About the details of the console.
KT315 transistors can be replaced with other silicon ones npn transistors with a static gain of at least 50. Fixed resistors - MLT-0.5, variable and tuning - SP-1, SPO-0.5. Capacitors - any type.
Transformer T1 with a ratio of 1:1, so you can use any one with a suitable number of turns. At self-production you can use a magnetic circuit Ш10x10, and wind the windings with PEV-1 wire 0.1-0.15, 150-300 turns each.
The diode bridge for powering thyristors (220V) is selected based on the expected load power, minimum 2A. If the number of lamps per channel is increased, the current consumption will increase accordingly.
To power transistors (12V), you can use any stabilized power supply designed for an operating current of at least 250 mA (or better, more).
First, each color music channel is assembled separately on a breadboard.
Moreover, the assembly begins with the output stage. Having assembled the output stage, check its functionality by applying a sufficient level signal to its input.
If this cascade works normally, an active filter is assembled. Next, they check again the functionality of what happened.
As a result, after testing we have a really working channel.
In a similar way, it is necessary to collect and rebuild all three channels. Such tediousness guarantees the unconditional functionality of the device after “fine” assembly on the circuit board, if the work is carried out without errors and using “tested” parts.
Possible printed circuit mounting option (for textolite with one-sided foil coating). If you use a larger capacitor in the lowest frequency channel, the distances between the holes and conductors will have to be changed. The use of PCB with double-sided foil may be a more technologically advanced option - it will help get rid of hanging jumper wires.
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In this topic I will try to talk a little about such a promising and popular lighting or decorative product as LED strip. What types there are, how to connect them and use them at home, what is called “on the knee,” without any special problems or special knowledge. And, as I already mentioned in other topics, it’s inexpensive. In this topic, I am not going to write something like “buy a device for 2.5 - 5 thousand rubles.” We can do it cheaper too. In this text I will only touch on tapes, and even then not every one, because I have not dealt with all their possible types and types. In any case, in this text, if I haven’t indicated something, it doesn’t mean that it doesn’t exist, it means that I haven’t come across it, or, more likely, I wasn’t interested in it. If something is indicated incorrectly for some cases, then it is correct within the specified framework. Perhaps in the next posts I will make some adjustments or additions to what has already been said.
What are LED strips called?
LED strips are lighting products on a flexible substrate (flexible board). They are a strip (tape) of plastic on which LEDs (SMD, or as they also say chip LEDs, sometimes ordinary LEDs), quenching resistors, or other LED control circuits are placed. The reverse side of the tape may have an adhesive layer (adhesive tape) for gluing it to any surface during installation. They are sold wound on reels. The maximum length of tape on a reel used for domestic purposes is most often 5 meters. They can be sold in cut and smaller pieces, for example by the meter, or any length divisible by 5 cm, depending on the seller’s decision on this issue.
LED strip is a kind of blank, semi-finished product, for creating lighting fixtures, or used as a means for decorative lighting, backlighting, etc. About the use of LED strips and rulers in everyday life, in the design of interiors, facades, shop windows, etc. you can find a lot of material on the Internet.
LED strips can hardly be used as “upper light”; their main purpose is illumination and various illuminations. For overhead light it is better to use fluorescent lamps, or LED bulbs higher power.
LED bars are called almost the same thing, only not on a flexible plastic, but on a rigid aluminum substrate, usually 20 - 50 cm long. Lines are also divided by power, number of LEDs, design, etc.
Based on the glow color of the ribbons, they can be divided into three groups:
- Monochrome, that is, the entire tape is one color, for example red, blue, green, yellow, cool white, warm white, etc.
- RGB color, they are assembled on special three-color RGB LEDs, and can emit different colors, depending on the emission intensity of each color. For example, the simultaneous glow of blue and red, with the green channel turned off, will give a color similar to lilac or purple, and all three channels with the same intensity will give a white color. But as experiments show, white color is still not very pure, therefore such tapes are used only for decorative purposes, and not for lighting.
- Multicolor (multi-colored) ribbons. Such tapes have separate groups LEDs of different colors (as opposed to RGB), for example 5 cm red, then 5 cm blue, etc. Although, obviously, in order to add confusion, they are also often called RGB strips. There are strips with separately controlled groups of LEDs, but there are others that do not have this feature.
There are other strips that have built-in controllers for various lighting effects, such as running lights, or more complex ones, both working on their own and controlled externally, but I won’t touch on those.
The strips also differ in the size of the LEDs, which means power consumption, I will talk about this below, their number, type of design - regular or protected for outdoor use, supply voltage, direction of radiation - normal or lateral, and many more parameters .
The marking of LED strips often consists of the following line: 3528/60 IP67 cold white 4.8W 12VDC ELK
This means that the strip consists of LEDs measuring 3.5x2.8 mm, has 60 LEDs per meter, full protection from dust, partial protection from water, color cool white, consumes 4.8 watts per meter, supply voltage 12V, manufacturer - ELK .
5050/60 cool white 14.4W 12VDC GREEN - LEDs 5.0x5.0 mm, 60 pieces per meter. Power supply 12V DC, power 14.4 watts per meter. Cool white color, manufacturer - GREEN.
5050/60 IP68 cold white 15W 220V - LEDs 5.0x5.0 mm, 60 pieces per meter, full protection from dust, can work for a long time under water no deeper than 1 m, consumes 15 watts per meter, is powered directly from a 220V network.
A little about color temperature: Sometimes in the designation of LED products there is a clause that may look like, for example, 2300K, 6400K, etc. This means that the color of the radiation of this product corresponds to the color of the radiation of an object heated to such a temperature in degrees Kelvin (0°K = -273.15°C). This means that the larger the number, the bluer the color, and the smaller the redder, and all the other colors are placed between them. You can notice that, for example, firewood burns with a red-orange flame, metal can be heated first to red, then to yellow and white, and an autogenous burner burns blue, like electrical discharges. Just for this reason. Sometimes they ask such a tricky question - which object Colorful temperature higher - near the sky or near the Sun? The correct answer is that the temperature in the sky is higher, since it is blue and the Sun is yellow.
But what is considered, for example, warm or cool white? It looks like color temperature has nothing to do with it. It is not physical laws that come into force here, but artistic ideas. Warm white is considered to be a physically colder color, that is, having a yellowish tint. And cold white has a bluish tint. Obviously due to the psychophysical perception of a person to whom yellow (Sun) seems warmer than blue (ice). From this we can assume that a warm shade will create coziness, and a cold one, on the contrary, will invigorate, although this is not at all necessary. As they say, there is no friend according to taste. For example, in all cases I prefer cold, simply because we have been lighting with warm lighting for millions of years, it’s time to try something different. Neutral white, or daytime white, refers to colors somewhere between warm and cool.
It is impossible to say which color is better. What color to use for illuminating various objects must be decided individually at the location, separately for each case. It seems to me that in the bedroom or children's room it is better to have a warm one, and in the hallway, in the bathroom, or in the kitchen, it is better to have a cold one. But not a fact.
Explanation of the IPxx standard: The first digit (0-6) is protection against the penetration of foreign objects, dust, and dirt. The second (0-8) is protection from water. The higher the number, the higher the protection. Zero - no protection. This shows that IP68 is the maximum protection from all influences. But there is no particular need to use such tape inside a living space. By the way, it is also more expensive than tapes with a lower degree of protection.
Power supply for LED strips:
First, let's understand the terms.
- Power supply (hereinafter referred to as PSU) is an electrical converter that generates the power supply voltage for the LED strip from some other power source, most often a 220V network. PSUs can be very different in design and version. Therefore, they must be chosen correctly for each use case.
- Transformer [for LED strips] - this is often called a power supply unit for LED strips, which, although they contain a transformer, are not actually transformers. They should under no circumstances be confused with the so-called. " electronic transformers"for halogen or other low-voltage incandescent lamps, which are also 12 volts, only produce alternating impulse voltage. Such “transformers” cannot be used for tapes. When using such a device, the tape may fail or operate unstable (flashing), and its service life will be greatly reduced. However, some sellers consider these devices to be one and the same, and they may be placed side by side in one place, which can cause confusion. You cannot also use conventional step-down transformers that are not equipped with rectifiers. Although the tape will glow, it will not last long, since LEDs, although they are diodes, are not designed to work with alternating voltage (they can be subject to reverse current).
- Driver - a control device for connecting LEDs to a power source. Essentially, it is a stabilizer or current regulator that powers an LED, or a group of LEDs. In our case, special drivers are not required, since their role is played by resistors placed directly on the tape.
- Dimmer - Brightness control, dimmer. I will talk about dimmers and how they can be inexpensively built below.
- Controller - Control device for LED strips. It can combine the functions of a driver and a dimmer, and/or create various lighting or color effects. Some controllers are equipped with remote controls.
- Power - electrical power in watts consumed by the tape. Has nothing to do with the power of incandescent lamps, with which LED or fluorescent lamps are often compared.
There are LED strips with different supply voltages, but I haven’t come across any other than strips with a 12V power supply. Perhaps such tapes are found most often. It is these tapes that will be discussed below. If anyone has tapes for other voltages, then throughout the text he must replace “12V” with the voltage of his tape.
The power supply for the tapes, or its documentation, must clearly state that the output is D.C.(DC), voltage is indicated (12V), either current (in amperes) or power (in watts) is indicated, and plus and minus are indicated on the terminals or in the documentation. When connecting LED strips, be sure to observe the polarity of the connection.
The power supply for supplying voltage to LED strips does not have to be any special; you can use any available power supply, both pulse and transformer, as long as they provide the required voltage and current. The choice of power supply depends on the load that the tape used will require.
BP can be stabilized or not stabilized. What does it mean? This means that a stabilized power supply maintains a given voltage regardless of the load and the supply voltage, within the limits for which it is designed. Unstabilized - without load, it has a slightly higher voltage, which decreases with increasing load. In addition, the output voltage depends on the supply voltage. Unstabilized power supplies are usually the simplest and cheapest, most often containing a transformer with a rectifier and a capacitor to smooth out voltage ripples. I can tell you how to make a simple transformer power supply separately, in another topic.
Let's consider a specific example of choosing a power supply - let's say we need to power 3 meters of tape at 12V, 8 Watts per meter. So in total it will be 8x3 = 24 watts. This means you need to take a power supply with a power of at least 24 watts.
Sometimes the power supply does not indicate the power in watts, but the current in amperes. Amps can be converted to watts using the formula P=UI, that is, power P is equal to the product of voltage U (in volts) and current I (in amperes). So in our case 24 = 12x?, from here we can see that the current is 2 A. So we need to find a power supply of any suitable design, 12V, with a current of at least 2 A. But it’s better with a reserve of current (power), for reliability, for example 2.5 or 3 amperes. In general, it is advisable to always choose a power supply that is 20-40% more powerful than required.
Not all stores indicate the full name of the LED strips; for example, the power or performance standard may not be indicated. In this case, you can determine the power by eye by the size of the LEDs and their number. And if you need accurate data, you can get it by measuring it yourself. Let's say there is one meter of RGB tape of unknown power. We connect all its channels (colors) to a powerful power source, using a voltmeter and an ammeter. Measurements give a voltage of 12.7 volts and a current of 1.1 amperes. Using the formula P=UI, we multiply one by the other. We get something like 14 watts per meter. But considering that our supply voltage was slightly higher than normal, we decide that the power is still about 12 watts. To power this segment, you need to select a 12V, 12 W power supply (or 1-1.5A).
If the power of the existing power supply is more than required, then there is no problem. If not very much less, then you can try to pray and connect the tape for a short time and see what happens. In this case, it is useful to connect a voltmeter or multimeter in parallel to the tape to evaluate the operation of the power supply. Commercially available power supplies may vary in quality. Some will not be able to develop even the rated power, and some are made with a very large margin of reliability and will withstand at least one and a half loads. Or they can work normally under increased load, only the output voltage will decrease. In any case, you should not operate the power supply if it becomes very hot, if there is a buzzing or whistling sound, as well as an unpleasant odor, and especially smoke.
The performance of the power supply cannot be checked “for a spark” by creating a short circuit. This action can instantly disable it, and repairs will cost more than buying a new one. This is especially true for inexpensive switching power supplies that do not have short circuit protection. During installation, it is necessary to exclude the possibility of spontaneous short circuiting.
Powering the tape with reduced voltage increases its service life. The minimum tape ignition voltage is about 7.5 volts.
You can try to serve a little increased voltage, for example, up to 14 volts, especially in cases where the tape operates from time to time, not for very long. In this case, be sure to check whether there is any dangerous heating of the LEDs and quenching resistors, and ensure natural air movement in the installation site, and remove dust more often. In this case, the service life will of course be reduced, but as I already said in another topic, it’s okay if the tape can work for five years, instead of working for ten, despite the fact that it will be thrown away after a year. Something should not always be built with grandchildren in mind, especially in our time, when something new is constantly appearing, and what is morally obsolete is thrown away in still working condition. The same applies to motorists who decorate their cars with ribbons. As you know, the voltage in a car, although it is considered 12 volts, can actually reach 15-16 volts. How long will a tape installed on a car to illuminate the underbody last in winter? And what will cause it to die first, from overvoltage or mechanical damage?
To be continued.
Most people listen to music with great pleasure using various equipment. Often there is a desire to enhance its positive impact. One of these methods is color music using diodes, made in the form of special attachments. Using diodes sound effects take on a completely different color, having a positive impact on the emotional mood of listeners. Such radio-electronic equipment is usually purchased ready-made, but if you have a diagram, certain knowledge and skills, it can easily be made with your own hands.
The principle of operation of color music on LEDs
The basis for the operation of each color music installation circuit is a physical principle associated with the frequency conversion of music. It is then transmitted through separate channels and controls the connected lighting devices. This chain connects the main musical characteristics with color elements that correspond to each other and work in mutual connection. This principle serves as the basis for all radio-electronic circuits in the field of color music, including those created independently.
Most often, the color scheme includes at least three different colors, such as red, green and blue. There are many combinations created by mixing them, so if the circuit is put together properly, it will definitely give the desired effect. To achieve this, the signal is divided and operates at low, medium and high frequencies Oh. The separation is carried out using special LC and RC filters installed in the common chain of the LED color music system.
There are certain parameters used when setting up filters that operate in their own narrow frequency band and transmit vibrations only in this segment of the sound range:
- LPF - low pass filters. The frequency of vibrations passing through them reaches 300 Hz, and the light source must be red.
- MFS - mid-pass filters. Capable of transmitting vibrations with a frequency from 250 to 2500 Hz, the color of the light source is yellow or green.
- High-pass filters are high-pass filters that pass more than 2500 Hz and work in conjunction with a blue light source.
The separated frequencies of the circuit slightly overlap each other, which makes it possible to obtain a variety of color shades during operation. The primary colors listed above are not of fundamental importance; it is quite possible to replace them with others - the most suitable for a particular situation. In some cases, the end result significantly exceeds expectations, thanks to the use of non-standard color solutions.
Schemes simple and complex
Getting acquainted with color music is revealed by the simplest scheme. As a rule, such devices use a minimum number of elements - just one LED, and one resistor and one transistor each. Power is supplied through a constant current source of 6-12V.
When assembled, LED color music is an amplification stage complemented by a common emitter. The main effect is exerted by a signal with varying amplitude and frequency arriving at the base. When the frequency exceeds the set threshold value, the transistor opens. At this moment, power is supplied to the LED and it immediately lights up.
Such a simple color music can be assembled using, for which an appropriate transistor is required. A significant drawback of this assembly is the direct relationship between the sound level and the blinking frequency LED light bulbs. That is, the system will work most effectively when supporting only one, the most suitable sound level. At a lower volume, the blinking will occur less frequently, and at high level sound, the light will become constant.
This drawback is easily removed by a three-channel sound converter, which is used in more complex schemes. In this case, a 9-volt power supply will be required to ensure normal lighting of the bulbs in the corresponding channels.
To assemble a circuit of three amplification stages, you need to stock up on KT315 transistors or their KT3102 analogues. LEDs of different colors serve as the load. The amplifying function is performed by a step-down transformer; resistors are used to regulate led flashes, and the above filters pass various frequencies through them.
This LED color music scheme can be further improved. First of all, this concerns the brightness of the glow, which is added by including small 12-volt incandescent light bulbs in the chain. In this case, the circuit is supplemented with control thyristors, and the entire device is powered through a transformer.
Using LED strips
Color music circuit with LED RGB tape operates on 12 volts. It best combines the basic parameters of conventional options. This device can work in different modes - as a lighting device or color and musical accompaniment.
The color music mode is activated using a microphone, in a non-contact manner. In case of switching to lighting mode, all available LEDs are simultaneously started on full power. The transition from one state to another is performed by a special switch, for which a separate board is provided.
The operating procedure of this scheme is as follows:
- The main signal arrives through a microphone, which transforms the sound vibrations of the phonogram. Since the strength of the received signal entering the color-music circuit is insignificant, it needs to be amplified. A transistor or a special amplifier is used for this purpose.
- Next, the automatic regulator starts up, keeping sound vibrations in within the established framework. At the same time, the sound is prepared for further processing.
- Using built-in filters, the signal is divided into three components, each of which has a separate frequency range.
- At the end of all actions, the current signal is amplified after its preliminary preparation using transistors operating in switch mode.
Main parts and components
Before you make equipment for color music with your own hands, you need to prepare all the parts and components in advance. In the circuit you should use only fixed resistors with a power range of 0.125-0.25 Ohms. The housings of the circuit elements are marked with special stripes indicating the resistance value. Additionally, trimming resistors R7, R10, R14, R18 are used. They can be different types, but the only requirement for them is the ability to mount on the board used for assembly.
Capacitors are designed for operating voltages of 16V and above. Any type of these devices can also be used in color music. If it is impossible to find a capacitor with the required parameters, it is allowed parallel connection two others, with smaller containers, which add up to the required indicators.
The created color and musical scheme cannot do without diode bridge. It is usually calculated for an operating current of up to 200 mA and a voltage of 50 volts. If you do not have a ready-made device, you can use several separate rectifier diodes and mount them for convenience on a separate small board.
The main colors of LEDs are red, green and blue. Their total number is determined based on one channel - 6 pieces. You will need standard transistors with any designation index. The voltage stabilizer with article number 7805 is designed for 5V, and the device for 9V is designated 7809. If you have experience, color music is assembled on an Arduino board and LEDs.
Compound music center carried out with color music various types three-pin connectors. The last part of the assembly is the transformer, which should have the most suitable voltage parameters.
Color music equipment in a car
Color music equipment is used not only at home. Many car owners install them together with radios. If necessary this system works as a backlight inside the cabin. For this type of lighting, LEDs are also used, placed on the ceiling in the “Starry Sky” configuration. This option is often used not only in cars, but also in the construction of suspended ceilings in apartments and private houses.
This layout scheme can be used in different ways when solving the problem of how to independently make color music from LEDs. First of all, this is a uniform distribution of LEDs in a certain configuration or in any form. The light bulbs used in the circuit may have different luminous power. That is, the stars simulated by LEDs can be bright or dim. The effectiveness of lighting largely depends on the background of the ceiling covering of the car or apartment.
If you install a color music system using LEDs yourself, you will have to re-tighten the ceiling during the installation process. In this regard, it is necessary to carefully select the necessary parts and then carefully assemble them into a single whole. In case of any violations, you will have to disassemble the interior covering and correct the errors. Therefore, upon completion of assembly, you should definitely check the functionality of the installed equipment.
After the color music is assembled, the LEDs are inserted into the ceiling holes and fixed on the back side with glue. It is also necessary to think in advance about reliable fastening of the voltage stabilizer and switch.
The inexhaustible potential of LEDs has once again been revealed in the design of new and modernization of existing color and music consoles. 30 years ago, color music, assembled from multi-colored 220-volt light bulbs connected to a cassette recorder, was considered the height of fashion. Now the situation has changed and the function of a tape recorder is now performed by any multimedia device, and instead of incandescent lamps, super-bright LEDs or LED strips are installed.
The advantages of LEDs over light bulbs in color music consoles are undeniable:
- wide color gamut and more saturated light;
- various design options (discrete elements, modules, RGB strips, rulers);
- high response speed;
- low power consumption.
How to make color music using a simple electronic circuit and make the LEDs blink from the source audio frequency? What are the conversion options? sound signal exist? Let's look at these and other questions using specific examples.
The simplest circuit with one LED
First you need to understand a simple color music circuit, assembled on one bipolar transistor, resistor and LED. It can be powered from a DC source with a voltage of 6 to 12 volts. This color music works on one transistor according to the principle of an amplification stage with a common emitter. A disturbing influence in the form of a signal with varying frequency and amplitude arrives at the VT1 base. As soon as the oscillation amplitude exceeds a certain threshold value, the transistor opens and the LED flashes.
The disadvantage of this simplest scheme is that the rate of blinking of the LED depends entirely on the level of the sound signal. In other words, a full-fledged color-musical effect will be observed only at one volume level. Lowering the volume will result in a rare wink, while increasing the volume will result in an almost constant glow.
Scheme with single-color LED strip
The simplest color music above on a transistor can be assembled using an LED strip in the load. To do this, you need to increase the supply voltage to 12V, select a transistor with highest current collector exceeding the load current and recalculate the resistor value. This simple color music from an LED strip is perfect for beginning radio amateurs to assemble with their own hands, even at home.
Simple three-channel circuit
A three-channel audio converter allows you to get rid of the shortcomings of the previous scheme. The most simple circuit color music with the division of the sound range into three parts is shown in the figure. 
It is powered by a constant voltage of 9V and can illuminate one or two LEDs in each channel. The circuit consists of three independent amplifier stages assembled on KT315 (KT3102) transistors, the load of which includes LEDs of different colors. As a pre-amplification element, you can use a small step-down network transformer.
The input signal is fed to the secondary winding of the transformer, which performs two functions: galvanically isolates the two devices and amplifies the sound from the line output. Next, the signal goes to three parallel-connected filters assembled on the basis of RC circuits. Each of them operates in a specific frequency band, which depends on the values of resistors and capacitors. The low-pass filter passes sound vibrations with a frequency of up to 300 Hz, as indicated by the blinking red LED. Sound in the range of 300-6000 Hz passes through the mid-pass filter, which is manifested in the flickering of the blue LED. The high-pass filter passes a signal whose frequency is greater than 6000 Hz, which corresponds to the green LED. Each filter is equipped with a trimming resistor. With their help, you can set the uniform glow of all LEDs, regardless of the musical genre. At the output of the circuit, all three filtered signals are amplified by transistors.
If the circuit is powered from a low-voltage DC source, then the transformer can be safely replaced with a single-stage transistor amplifier. 
Firstly, galvanic isolation loses its practical meaning. Secondly, the transformer is several times inferior to the circuit shown in the figure in terms of weight, size and cost. The circuit of a simple audio amplifier consists of a KT3102 transistor, two capacitors that cut off the DC component, and resistors that provide the transistor with a common emitter. Using a trimmer resistor, you can achieve overall amplification of a weak input signal.
In the case when it is necessary to amplify the signal from the microphone, connect to the input of the previous circuit electret microphone, applying potential to it from the power source. Two-stage circuit preamp shown in the figure. 
In this case, the trimming resistor is located at the output of the first amplifier stage, which gives more opportunities for adjusting sensitivity. Capacitors C1-C3 pass the useful component and cut off the direct current. Any electret microphone is suitable for implementation, for which a bias of 1.5V is sufficient for normal operation.
Color music with RGB LED strip
The following circuit of a color music console operates on 12 volts and can be installed in a car. It combines the main functions of the previously discussed circuit solutions and is capable of operating in color music and lamp modes.
The first mode is achieved through contactless control of the RGB strip using a microphone, and the second mode is achieved through the simultaneous illumination of red, green and blue LEDs at full power. The mode is selected using a switch located on the board. Now let’s take a closer look at how to make color music that is perfect even for installation in a car, and what parts are required for this.
Structural scheme
To understand how this color music console works, let’s first look at it block diagram. It will help trace the full path of the signal. 
The source of the electrical signal is a microphone, which converts sound vibrations from the phonogram. Because This signal is too small and must be amplified using a transistor or operational amplifier. Next comes the automatic level controller (AGC), which keeps the sound fluctuations within reasonable limits and prepares it for further processing. Filters divide the signal into three components, each of which operates only in one frequency range. In the end, all that remains is to amplify the prepared current signal, for which transistors operating in switching mode are used.
Schematic diagram
Based on the building blocks, we can proceed to consider schematic diagram. Its general appearance is shown in the figure. 
To limit current consumption and stabilize the supply voltage, resistor R12 and capacitor C9 are installed. R1, R2, C1 are set to set the microphone bias voltage. Capacitor C fc is selected individually to specific model microphone during setup. It is needed in order to slightly muffle the signal of the frequency that prevails in the microphone’s operation. Usually the influence of the high-frequency component is reduced.
Unstable voltage in the vehicle network can affect the operation of color music. Therefore, it is most correct to connect homemade electronic devices through a 12V stabilizer.
Sound vibrations in the microphone are converted into an electrical signal and, through C2, are supplied to the direct input of the operational amplifier DA1.1. from its output the signal goes to the input of the operational amplifier DA1.2, equipped with a circuit feedback. The resistances of resistors R5, R6 and R10, R11 set the gain DA1.1, DA1.2 equal to 11. The elements of the OS circuit: VD1, VD2, C4, C5, R8, R9 and VT1, together with DA1.2, are part of the AGC. At the moment a signal of too large an amplitude appears at the output of DA1.2, transistor VT1 opens and, through C4, closes the input signal to the common wire. This results in an instantaneous reduction in the output voltage.
Then stabilized alternating current The audio frequency passes through the cut-off capacitor C8, after which it is divided into three RC filters: R13, C10 (LF), R14, C11, C12 (MF), R15, C13 (HF). In order for the color music on LEDs to shine brightly enough, you need to increase the output current to the appropriate value. For tape with a consumption of up to 0.5A per channel, medium-power transistors such as KT817 or imported BD139 without mounting on a radiator are suitable. If the do-it-yourself light-music assembly involves a load of about 1A, then the transistors will require forced cooling.
In the collectors of each output transistor (parallel to the output) there are diodes D6-D8, the cathodes of which are connected to each other and connected to switch SA1 (White light). The second contact of the switch is connected to the common wire (GND). While SA1 is open, the circuit operates in color music mode. When the switch contacts are closed, all the LEDs in the strip light up at full brightness, forming a total white stream of light.
Printed circuit board and assembly parts
For the manufacture of printed circuit board You will need a one-sided textolite measuring 50 by 90 mm and a ready-made .lay file, which can be downloaded. For clarity, the board is shown from the side of the radio elements. Before printing, you must set its mirror image. Layer M1 shows 3 jumpers placed on the parts side. 
To assemble color music from an LED strip with your own hands, you will need accessible and inexpensive components. An electret type microphone, suitable in a protective case from old audio equipment. Light music is assembled on a TL072 chip in a DIP8 package. Capacitors, regardless of type, must have a voltage reserve and be designed for 16V or 25V. If necessary, the board design allows you to install output transistors on small radiators. A terminal block with 6 positions is soldered on the edge for supplying power, connecting an RGB LED strip and a switch. A complete list of elements is given in the table. 
In conclusion, I would like to note that the number of output channels in a homemade color music set-top box can be increased as many times as desired. To do this you need to break the whole frequency range to a larger number of sectors and recalculate the bandwidth of each RC filter. Connect LEDs of intermediate colors to the outputs of additional amplifiers: violet, turquoise, orange. Do-it-yourself color music will only become more beautiful from such an improvement.
The given diagrams belong to the site cxem.net
Read also
This LED color music is suitable for those who listen to music on the computer. It can be placed inside the case and it will be illuminated to the beat of the music.
The color music scheme is very simple and does not present any difficulties.
Required components:
1. 4 LEDs (any color) 3mm
2. P2 plug
3. 2 position switch
4. Bipolar transistor TIP31
5. The box (if needed) can also be placed directly in the computer case
6. Soldering iron
7. Cable
We connect 4 LEDs to +12 V of the computer, connect the anode to a 2-position switch, which in turn connects to bipolar transistor TIP31. We connect the two unused ends of the transistor directly to the terminals of the plug for headphones or speakers P2.
We install all assembled components in a box (box), or directly into the computer case - this is up to everyone’s own discretion. We made holes for the LEDs, switch and plug.
Installation of LED color music in a box
Let's connect the LEDs, transistor and switch
1 of 2
Connecting LEDs
General assembled view with transistors
Next comes the most interesting part. It is necessary to solder the LEDs together, the transistor and the switch. From the photographs it is clear without words. The only thing is that we had to select the length of the conductors so that they would fit in the box.
We connect the common negative from the LEDs to the middle contact of the switch. From the switch, one of the positions is connected to the middle pin of the transistor, connect the second position according to the color music diagram that we presented above.
Installation of wires to plug P2
Final stage
1 of 2
Installation of diode color music circuit
Soldered plug
If we disassemble the headphone plug, we can see three connectors inside - left and right channels, ground. We connect one of the channels to the left pin of the Tip31 transistor. If P2 is connected through the left channel and it does not “beat” with the computer output, then our circuit will not work. Therefore, immediately decide correctly or experiment. Ground (usually a long connector) should be connected to the right pin of the transistor.
One of the switch pins should be connected to ground from the transistor. With this connection, the LEDs will start blinking if there is any signal at the output. If there is no signal coming from connector P2, if there is a signal on the other side, they will light up constantly.
We mount everything in the box, connect it and check its functionality.
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