They are an element of the equipment control system. These devices are currently actively used for acoustics. You can make a model for headphones yourself. However, there are complex amplifiers based on output transformers. They are intended mainly for speakers of various powers.
Important parameters of the models include frequency and sensitivity of the equipment. Depending on the power of the power supplies, the output voltage varies. In order to understand this issue in more detail, you need to consider the design of a simple amplifier.
A simple tube amplifier consists of a capacitor, power supply and resistors. Transistors in devices are often used of the orthogonal type. The lamps themselves are used at 6 W. Regulators for models are selected of both push-button and rotary types. Modulators in amplifiers are mainly pulsed, but code modifications also exist. To increase the frequency of the device, elements such as arresters are used. Some models have thyristors. They reduce the output voltage quite significantly. In this case, the capacitors do not experience large overloads. Cassette regulators are rarely used in models of this type.
A single-ended tube amplifier is used for power outputs not exceeding 20 watts. In this case, transformers are usually used as output type. Field capacitors themselves are often used. In this case, lamps can be safely selected at 15 W. The sensitivity of such devices is highly dependent on resistors. As a rule, they are installed orthogonally on a single-ended tube amplifier at the beginning of the circuit.
Thyristors are never used in such models. This is due to the fact that the resistance in the circuit is quite variable. It is also important to note that the voltage should be adjusted using a controller. Acoustics for a tube amplifier are connected via a two-wire port. Models most often use a contact modulator. On average, the negative resistance parameter is at the level of 50 Ohms. It is also important to note that sensitivity is greatly reduced in amplifiers when using copper conductors.
It is very difficult to make a push-pull tube amplifier with your own hands. Step-by-step instructions in this regard will be very useful. For assembly, you will need an output type transformer. The easiest way to install resistors on push-pull tube amplifiers is single-pole. You will need two capacitors at the input. They must withstand a minimum of 60 ohms of negative resistance in the circuit. In this case, the sensitivity of the devices can reach up to 3 microns.
To minimize failures in modulators, trimming resistors are used. Conventional field capacitors are installed at the output of the system. Power supplies for push-pull tube amplifiers are suitable even at 30 V. Cassette regulators are almost never used in such devices. The input voltage parameter in amplifiers is on average 15 V. The amplitude of oscillations in this case depends on the frequency of the signal.
Hybrid tubes are a set of output transformer and half-duplex resistors. In order to assemble the model yourself, you will need a 40 V power supply. Orthogonal type resistors are used directly at the input of the circuit. They must withstand negative resistance at 55 Ohms. In this case, it is more appropriate to install thyristors behind the output transformer.
The lamps are soldered in sequential order. The frequency of the model depends on the amplitude of magnetic oscillations. The output voltage parameter of the devices can be easily adjusted using a controller. After installing the orthogonal resistors, a power supply is installed on the tube audio amplifiers. In this case, the throttle must be directly connected to the controller. Acoustics for a tube amplifier must be connected via a two-wire port. At the last stage of assembly, you should check the output voltage of the transformer. For normal operation of the system, this indicator should not exceed 15 V.
It is quite difficult to make a low-frequency tube amplifier with your own hands. Step-by-step instructions can help a lot. Many experts recommend starting with installing a transformer. In this case, field-type resistors will be required. Their conductivity is good and they can last quite a long time. It is important to solder a capacitor at the input of the circuit. In this case, an orthogonal type model will work well. At the next stage, it is more advisable to deal directly with the controller to adjust the device.
In some cases, it is selected as a rotary type. The minimum frequency should be set at 500 Hz. In this case, the lamps are soldered in sequential order. It is better to use a coaxial cable to connect the transformer to the controller. To check the equipment, the output voltage parameter is first measured. In this case, it is important to consider the power of the power supply. Most often, it is selected at 20 V. In this situation, the negative resistance parameter should not exceed 45 Ohms.
High-frequency tube power amplifiers belong to the class of push-pull modifications. Their difference lies in the presence of power transformers. All this is necessary to increase signal conductivity. The maximum device frequency parameter can reach up to 500 Hz. In this situation, it is more expedient to start assembling the model with the installation of the transformer.
You can choose a wooden panel for this. In this case, the controller must be installed on a lining. In this case, the output voltage can always be checked using a tester. The block itself is used in a 30 V circuit. In this situation, the transistors are soldered to the beams. They must withstand negative resistance in the system of at least 43 ohms. All this will allow you to easily regulate the frequency of the equipment.
In this case, the lamps are soldered in sequential order. Capacitors are used of both orthogonal and capacitive types. In this situation, a lot depends on the type of controller. If we consider push-button modifications, then we cannot do without a thyristor. With rotary controls, you can use a regular modulator.
It is very difficult to make this type. Step-by-step instructions in this regard will be very useful. Many experts advise building an amplifier based on electrolytic capacitors. It is important to start directly assembling the model with the installation of the transformer. In this case, the lamps are soldered in sequential order.
Resistors in the models use beam type. However, orthogonal analogues are installed at the input of the circuit. Zener diodes are used in this situation if the power supply is rated at 30 V. Otherwise, the modulator copes well with network overloads. The controller is connected in the amplifier behind the transformer. Comparators are used to increase the sensitivity of the model. The minimum element frequency must be 300 Hz. In turn, the negative resistance indicator should not exceed 50 Ohms.
Models of this type are very common today. The transformer for a tube amplifier must be selected as a power transformer. It should also be taken into account that controllers should only be used of the cassette type. The modulators themselves are installed with expanders. All this gives a significant increase in signal conductivity.
The sensitivity of the model in amplifiers depends on the types of resistors. If we talk about a 20 V power supply, then it should be selected of an orthogonal type. Otherwise, preference can be safely given to single-contact analogues. At the same time, field-effect resistors will not be able to provide high frequencies. The easiest way to regulate oscillations in the network is through thyristors. In this case, the output voltage in the system should not exceed 15 V.
It is quite difficult to make a tube amplifier with your own hands using a step-down transformer. Step-by-step instructions can help a lot. It is best to use orthogonal resistors for the amplifier in this situation. However, it is important to start assembling the model by installing the power supply. Then the lamps should be connected to the panel. In this case, capacitors can be used. They must keep the negative resistance at 33 ohms. All this will stabilize the frequency at low overloads. Thyristors are used very rarely in circuits of this type. However, if we talk about high-frequency models, then they will be appropriate.
You can create an amplifier with only if you find a high-quality comparator. Also, in this situation, you cannot do without tuning resistors. It is recommended to start assembling the model from the panel. The lamps should be installed in sequential order. The power supply in this situation must be connected directly to the inductor.
The negative resistance in the circuit should not exceed 55 Ohms. In this case, the output voltage depends on the power of the power supply. Modulators in such devices are available with switches. All this allows you to quickly reduce the frequency when the load on the capacitors increases sharply. Beam transistors in models must be installed behind the transformer. When soldered at the beginning of the circuit.
To make an amplifier with a pulse transformer, the panel is first prepared. The easiest way is to choose a plastic one. In this situation, the lamps must be connected in series order. The transformer must be placed on a lining. In this case, a capacitor at the beginning of the circuit will be required of the capacitive type. The power supplies for the models are selected for 30 V. All this ultimately ensures good signal conductivity. The modulator is considered an integral element of the amplifier.
It should not be installed behind a pulse transformer. In this case, the load on the capacitors will be greater. To avoid circuit failures, a thyristor should be used to reduce sensitivity. It must withstand negative resistance at 35 ohms. Transistors in the system are installed behind the transformer. Code modulators can be used directly. In stores they are most often sold with the PP20 marking. Their distinctive feature is the presence of a broadband head. Thus, the frequency of the device can be adjusted more smoothly.
For computer headphones, capacitors can be used of the electrolytic type. In this case, high sensitivity is not required from the model. To suppress interference in systems, various types of thyristors are used. It is more advisable to use modulators of the tuning type. The output voltage in the circuit should not exceed 12 V.
In order to regulate the frequency of the amplifier, compact controllers are soldered. In this case, the lamps should be installed in sequential order. The power supply is connected via a choke. Duplex resistors are used very rarely in such circuits.
The kit for a tube amplifier should be selected only in specialized radio stores. First of all, you will need beam transistors. In this case, it is important to install the modulator on the panel. Capacitors are used with low capacity. During assembly, special attention should be paid to the selection of the controller. Two-contact models are ideal for such systems. However, it is better not to consider devices with comparators.
Lastly, the power supply itself is fixed. The bandwidth of such systems is usually low. However, it should be borne in mind that problems with hypersensitivity are quite common. This happens in most cases due to burnt-out capacitors. The problem can be solved very simply by installing an auxiliary fuse.
A homemade tube of this type is capable of producing an average frequency of 550 Hz. In order to assemble the model, a regular power transformer is quite suitable. In this case, capacitors can be used orthogonal. Directly at the beginning of the circuit, resistors are used with low resistance.
Thanks to this, sudden jumps in the system rarely occur. The modulator must be installed behind the transformer. In this situation, it is imperative to use a lining. The tube amplifier must be powered via a 20 V power supply.
A comparator is used to increase the output voltage. Most often it is selected as a network type. On average, it can keep negative resistance at 45 ohms. After installing the comparator, you can screw on the lamps. To avoid feedback effects, it is more advisable to use electrolytic capacitors.
DIY TUBE AMPLIFIER
I was convinced of the superiority of tube sound over transistor sound after the first amplifier I assembled and listened to. Despite all the new microcircuits, transistors and other “stones”, vacuum is still preferable for high-quality ULF. Whatever one may say, an audio signal passing through emptiness has less distortion than passing through germanium and silicon. Moreover, the difference is especially noticeable when listening to two amplifiers alternately. In order not to buy expensive branded LUNCH, you can doDIY tube amplifier.For those who decide to see this for themselves, a simple classical scheme is offeredtwo-stroketube amplifier with a power of approximately 20 watts per channel,from the site radiostation.ru.
For trance power, we take the good old TS180-2 from the TV. Output transformers are TN type, but TANs can also be used.Using all the resources of military production and the invaluable help of Uncle Vadim in creatingtube amplifier, I managed to make such a device:
basistube amplifier,is a duralumin plate 200x160 mm, 4 mm thick, on which parts and lamps are attached. Then the entire structure is painted white (tired of black boxes) and racks made of polished alloy D95 are screwed into the corners. Power and output transformers are placed in tin screens to reduce background and interference.
To save space, the power choke was eliminated, and instead a simple P-filter is used, a 300 µF capacitor - a 15 W 100 ohm resistor - a 300 µF capacitor. Backgroundtube amplifier in speakers,Can't be heard even in silence.
There is a lot of debate about the advantages and disadvantages of low (audio) frequency tube amplifier circuits. There are, indeed, entire separate movements of tube sound, with their own gurus and adherents. “Only tubes, no semiconductors”, “hybrid”, “single-ended”, “fans of transformers (interstage)” and hybrids and subspecies. This applies to homemade workers, who deserve respect in any case. There are still those for whom fooling their neighbor is their profession. It's really bad there. Of course, there are exceptions everywhere.
Let’s not touch on “theology” now, but let’s see what we managed to make out of literally trash.
Perhaps it’s worth starting with the fact that we came to the Perm region to look for a place to live, mainly with the most necessary things, and radio components were not one of them. Fortunately, in the city there was a store selling radio components, with a unique assortment, however, what was discovered was fortunate. The radio elements required for a tube amplifier are somewhat specific, not counting the radio tubes themselves. In a word, having thought about it, he advertised in the local newspaper for the purchase of a tube radio. They called a lot, gave a few away just like that, with the condition “pick-up-from-the-garage-yourself.” There were as many as four pieces, then the relatives rebelled, and it was awkward to insist - at that time we were temporarily living with our parents, and I was making crafts with my grandmother in the private sector. Fortunately, the two radios turned out to have very similar internals - a typical 6P14 low-frequency amplifier circuit, and the power supply is the same. “Our Alena Igorevna has such a typical, typical appearance.”
The first treacherous thought, which I barely managed to smother with a pillow, was to simply take and transfer these amplifier scarves to a separate box and... and that’s all. But firstly, it wouldn’t be very aesthetically pleasing (What about the main highlight, the lamps on the outside? It’s a show off, of course, but it’s beautiful). Yes, on printed circuit boards - well, no. In a word, it was decided to refuse the easy way; this is not the first time we’ve smelled rosin in tea! So that everything is like people... (singing under his breath) everything is like people. Yes, hmm, well, I laid out the tubes pulled from the radio on a cloth on the workbench, sketched out a circuit, a power supply, so that all the voltages were stabilized, that’s all. Output tubes 6P14, triode-pentode switching, output transformers like TVZ 1-9, input stage 6N2P, but I left the approval for later, after experiments.
We had never seen decent ceramic lamp panels in the store, so we had to get out of it.
High side walls, only partly for simplicity. Largely for convenience - it doesn’t do a bad job of protecting fragile and breakable radio tubes, and given the upcoming construction in the village, it’s not at all clear where the device will be carried around. Again, it’s very convenient to set up and redo - turn it over and stand rooted to the spot, and you don’t even need to take out the lamps - solder, measure, turn on as much as your heart desires.
Radiator on top for stabilizers, high-voltage and filaments. Rectifiers for them are in the chassis basement.
The body was disassembled, putty, sanded, a couple of layers of paint.
Assembly of the case is complete.
Mounted are power switches (incandescent and delayed anode), power indicators on neon bulbs, lamp sockets, output stage mode switches - triode-pentode, and feedback switches.
The rectifiers are installed in the basement, the fuse is on the back wall in the fittings, everything is connected, we carefully check the operation of the finished piece of the circuit directly from the network. The lamps stick out for ambience.
Everything works, hurray.
Queue for the power transformer. This one is from the same radio. The power should be quite enough. The casing was removed from the magnetic core, and four studs made from long M6 bolts were soldered to it. For installation sideways in a sort of lying position, so that all the wires are in the basement of the chassis. I boiled the coil in varnish to prevent it from buzzing.
High-voltage rectifiers have been installed and already tested, there are already four of them - each cascade of two channels has its own. Each diode is shunted by a film capacitance against interference during switching.
Electrolytic capacitors are here, including those from stabilizers. The stabilizers themselves will be on top of the radiator.
Power switches and neon indicator lights are connected. The signal sockets and the shielded cable to the first stage are visible.
Plank, no, not Picatinny - Mazaya. Contact. It will be attached to the screws of the transformer inside the housing. The rectifier diodes of all lamps are conveniently soldered on it. Stabilizers, again outside on a common radiator.
Stabilizer +5 volts. With USB socket. For the convenience of MP3 player operation. So as not to run around looking for a charger or a computer. The usual 7805, in the classic configuration - two electrolytic and two ceramic capacitors. Powered by a filament rectifier.
Oh, the transformer is in place. Charging too. The contact strips are placed on the transformer mount, three diode bridges with electrolytes are soldered onto them, and charging for the MP3 device is turned on.
Scarf with stabilizers. High-voltage on discrete elements, three filament stabilizers in the middle - on 7806, plus one or two (pick up) diodes in the common output.
On the other side of the board are power elements.
And inverted, so as to press them with their backs to the radiator. The board is also made in a somewhat original way - in the same way as with SMD elements, so that there are no tracks or pins on the radiator side. Still high voltage.
This is by the way.
There is a clear cover on top to prevent your fingers from getting into the high voltage. The radiator is standard, needle-shaped, the cover is made of galvanized steel 0.5 mm.
PSU tests. Connections between the rectifier and stabilizer on a live thread.
The hardest part is putting it in place and installing it. Radiator with stabilizers on the other side of the chassis. All wires collected in four bundles are threaded through the holes and routed to the rectifier. With tweezers, with a little patience and care. Then the main fun begins - using a tester to look for which end of the wire and connect it according to two circuits, so that nothing unnecessary sticks out, and so that “and be careful not to confuse ... Kutuzov.” Otherwise the fireworks might be great, we swam, we know.
These are the amplification stages themselves, in person, so to speak. Well, everything is like with people. Automatic bias, interstage capacitors like fluoroplastic, let’s be curious.
Output transformers.
From radio receivers, it’s clear that they are boiled in wax and paraffin, the core is hot pulled together in a vice through a strip of elastic - so that the non-magnetic gap in each layer of iron is the same and minimal. When disassembling and reassembling, do not lose a strip of paper for a non-magnetic gap.
And in an improvised casing from a condensed milk can.
Fill it with wax, or neutral sealant, or epoxy resin, if you don’t mind.
Output transformers are in place.
Listening in grandma's greenhouse, where there is more space. Well, I like it.
The acoustics were like this, the acoustic design is a “closed case”, it plays well, but the sensitivity is not enough, you have to mainly turn on the output stage with a pentode.
This is with a shroud on the radiator.
After working for some time, one of the output transformers burned out and had to be rebuilt with others.
DIY tube amplifier aslan wrote in May 19th, 2018
A person whom I once helped in searching for radio tubes contacted me. This time he needed help in repairing the amplifier that he had assembled using these tubes: a strong hum appeared in one channel, which he could not overcome.
Here we need to say a few words about the customer himself - he is a brutal guy with a biker look, with a thick black beard and tattoos, and at the same time a kind-hearted man. His occupation, which matches his appearance, is repairing motorcycles. In electronics, he, in his own words, understands nothing. Everyone wouldn’t “understand” that they could assemble their own tube amplifiers, but oh well)
I agreed to help him, and soon he brought me this miracle: 
The amplifier housing turned out to be welded from a 2-mm steel sheet, which was then further aged and coated with copper. Fortunately, photographs of the work process have been preserved, so with the permission of the author I will share them:
All work was done by hand using a grinder, drill, files and, of course, a welding machine.
The design intricately combines modern elements and parts from Soviet radio technology.
I really liked the textured coating of the case, and I even seriously thought about whether I should use something similar in my own projects.
In general, the amplifier was left to me with a request to repair it as soon as possible. I connected it to the speakers and was convinced that there was a strong hum in one channel. As you know, electronics is the science of contacts, so something is probably unsoldered somewhere, or, conversely, shorted out. This can be fixed quite quickly, I thought naively.
When I first looked into the "basement", at first glance everything looked good - at least for an amplifier made by an absolute beginner. The author simply took and installed two low-frequency amplifier boards from the Ural-112 radio radio inside.
But since the location of the lamps and transformers did not suit him, he desoldered them and carefully built up all the connections with wires.
Unfortunately, lamp technology does not tolerate such installation: long wires, repeatedly intertwined and crossing each other, collect all imaginable noise and interference. In addition, the author used a single-color MGTF wire, and it was almost impossible to figure out what went where. And there was no point in keeping the original boards: their only advantage, which was that they could be installed “as is” and save time and effort, was lost, and only disadvantages remained.
Let's say, in the power part, obsolete selenium rectifiers and huge resistors of the BC type, which were used only in the power circuit of the high-frequency radio unit (R5, R1 and R8), were in vain taking up space. But the resistive divider R3-R4, which was supposed to supply a small positive voltage to the midpoint of the filament winding to reduce the noise level, was lost during the transfer process.
It is worth noting that this “not versed in electronics” person himself (albeit using a ready-made circuit) soldered the display unit on “magic eye” lamps, and even with a separate amplifier on a 6N2P lamp, which made it independent of the output level volume. True, huge 2-watt resistors were used (although 0.25-watt ones would have been enough) - he installed them according to the principle “too much is not too little” so that there would definitely not be overheating. Here is such an amazing combination of ingenuity, direct hands and, moreover, a complete lack of experience, leading to slightly curious, but still impressive results.
Acting on a whim, the author made two channels of the amplifier completely mirrored - each with its own power transformer. This also turned out to be redundant, since now there was no need to power the lamps responsible for radio reception. The second transformer only got in the way, and even made a loud noise, because its plates had become loose over time, and the design did not allow them to be tightened securely.
In general, I realized that there is no quick repair here, and the amplifier needs to be completely redone. The situation was complicated by the fact that in just a couple of days I had to fly away on vacation. As a result, I soldered the last parts at night right in front of the customer, and the next morning, having slept a little, I was already rushing to the airport) But everything turned out as it should, and the customer was pleased with the pleasant sound of the amplifier and the absence of noise. And I only realized later that in my haste I completely forgot about photographing the work process.
There is, however, a frame in which I use a battery and a microammeter to determine the direction of the windings of a power transformer.
In fact, it took a lot of work. After all, I, in fact, was forced to do double work: first, disassemble the amplifier to zero, and then reassemble it, but this time correctly. During this process, 95% of radio components were replaced with modern ones. All that remained were the electrolytes in the power supply - their polished cases were an element of the external design. They were well preserved, so that their total capacity was sufficient to ensure that the background of the alternating current was not detected by the ear at a distance of 20 cm from the speaker.
When working, I followed the basic rules of overhead “lamp” installation - minimizing (within reasonable limits) the length of conductors, spacing signal and supply lines in space, mutually perpendicular orientation of power and output transformers, shielding, avoiding ground loops, etc.
While on vacation, I had already begun to slowly forget about this project, when suddenly the customer sent me photographs that captured something very interesting:
Taking advantage of the lack of an extra power transformer, he made a new two-tier casing for the amplifier.
Harsh tube amplifier tube amplifier, homemade products, modding, Alcatraz, equipment repair, long post
It was no coincidence that the square holes in it appeared: it was decided to stylize the body as the building of the Alcatraz prison! Well, what would Alcatraz be without a lighthouse?
In the end it turned out like this:
The beacon is made removable and attached with a magnet. And the light in it doesn’t just light up, but shows whether the built-in Bluetooth module is turned on, which is one of the possible signal sources for the amplifier.
This is how the ability to work with metal and the rich imagination of the author, combined with my modest knowledge of lamp technology, led to the birth of a very unusual and functional device. I think a good name for it would be "The Rock".
People who love good music probably know about the Hi-End tube amplifier. You can do it yourself if you know how to use a soldering iron and have some knowledge of working with radio equipment.
Hi-End tube amplifiers are a special class of household appliances. What is this connected with? Firstly, they have some pretty interesting design and architecture. In this model, a person can see everything he needs. This makes the device truly unique. Secondly, the characteristics of a Hi-End tube amplifier differ from alternative models that use Hi-End. The difference is that a minimum number of parts are used during installation. Also, when evaluating the sound of this device, people trust their ears more than nonlinear distortion measurements and an oscilloscope.
The preamplifier is quite simple to assemble. For it, you can choose any suitable scheme and start assembling. Another case is the output stage, that is, a power amplifier. As a rule, many different questions arise with it. The output stage has several types of assembly and operating modes.
The first type is a single-cycle model, which is considered a standard cascade. When operating in “A” mode, it has slight nonlinear distortion, but, unfortunately, has rather poor efficiency. Also noteworthy is the average power output. If you need to fully sound a fairly large room, you will need to use a push-pull power amplifier. This model can operate in “AB” mode.
In a single-ended circuit, only two parts are enough for the device to work well: a power amplifier and a pre-amplifier. The push-pull model already uses a phase inverted amplifier or driver.
Of course, for two types of output stage, in order to work comfortably with, it is necessary to match the high interelectrode resistance and the low resistance of the device itself. This can be done using a transformer.
If you are a connoisseur of “tube” sound, then you should understand that you need to use a rectifier, which is produced on a kenotron, to achieve such a sound. In this case, semiconductor parts cannot be used.
When developing a Hi-End tube amplifier, you don't have to use complex circuits. If you need to sound a fairly small room, then you can use a simple single-cycle design, which is easier to make and configure.
Before starting installation, you need to understand some rules for assembling this type of device. We will need to apply the basic principle of installing lamp devices - minimizing fasteners. What does it mean? You will need to discard the mounting wires. Of course, this cannot be done everywhere, but their number must be minimized.
In Hi-End, mounting tabs and strips are used. They are used as additional points. This type of assembly is called hinged. You will also need to solder the resistors and capacitors that are on the lamp panels. It is highly not recommended to use printed circuit boards and assemble conductors so as to create parallel lines. This will make the assembly look chaotic.
Later, you need to eliminate the low-frequency background, if, of course, it is present. Another important point is the choice of grounding point. In this case, you can use one of the options:
In general, it is better to find a grounding point yourself. This can be done by determining the level of low-frequency background by ear. To do this, you need to gradually close all the grids of lamps that are located on the ground. If, when the subsequent contact is closed, the low-frequency background level decreases, then you have found a suitable lamp. To achieve the desired result, it is necessary to experimentally eliminate unwanted frequencies. You should also apply the following measures to improve the quality of your build:
If you want to power the preamp tubes, you can use DC current. Unfortunately, this requires connecting an additional unit. The rectifier will violate the standards of a Hi-End tube amplifier, since it is a semiconductor device that we will not use.
Another important point is the use of different transformers. As a rule, power and output are used, which must be connected perpendicularly. This way you can reduce the level of low-frequency background. Transformers should be located in grounded enclosures. It must be remembered that the cores of each transformer should also be grounded. There is no need to use it when installing devices to avoid additional problems. Of course, these are not all the features associated with installation. There are quite a lot of them, and it will not be possible to consider them all. When installing a Hi-End (tube amplifier), you cannot use new element bases. They are now used to connect transistors and integrated circuits. But in our case they will not work.
A high-quality Hi-End tube amplifier is a retro device. Of course, the parts for its assembly must be appropriate. Instead of a resistor, a carbon and wire element may be suitable. If you spare no expense in developing this device, you should use precision resistors, which are quite expensive. Otherwise, MLT models are applicable. This is a pretty good element, as evidenced by the reviews.
Hi-End tube amplifiers are also suitable for use with BC resistors. They were made about 65 years ago. Finding such an element is quite simple; you just need to walk around the radio market. If you are using a resistor with a power of more than 4 Watts, you need to choose enameled wire elements.
In a tube amplifier setup, you should use different types of capacitors for the system itself and the power supply. They are usually used to adjust the tone. If you want to get high-quality and natural sound, you should use a coupling capacitor. In this case, a small leakage current appears, which allows you to change the operating point of the lamp.
This type of capacitor is connected to the anode circuit, through which a large voltage flows. In this case, it is necessary to connect a capacitor that maintains a voltage greater than 350 volts. If you want to use quality parts, you need to use parts from Jensen. They differ from analogues in that their price exceeds 3,000 rubles, and the price of the highest quality radio elements reaches 10,000 rubles. If you use domestic elements, it is better to choose between the K73-16 and K40U-9 models.
If you want to use a single-cycle model, you must first consider its circuit diagram. It includes several components:
Let's start the assembly with the pre-amplifier. Its installation follows a fairly simple scheme. It is also necessary to provide power control and a separator for tone control. It should be tuned to low and high frequencies. To increase shelf life, you need to use a multi-band equalizer.
In the laughter of the preamplifier you can see similarities with the common 6N3P double triode. The element we need can be assembled in a similar way, but use the final cascade. This is also repeated in stereo. Remember that the structure must be assembled on a circuit board. First it needs to be debugged, and then it can be installed on the chassis. If you installed everything correctly, the device should turn on immediately. Next you should move on to configuration. The value of the anode voltage for different types of lamps will differ, so you will need to select it yourself.
If you do not want to use a high-quality capacitor, then you can use K73-16. It will be suitable if the operating voltage is more than 350 volts. But the sound quality will be noticeably worse. Electrolytic capacitors are also suitable for this voltage. You need to connect the C1-65 oscilloscope to the amplifier and submit a signal that will pass from the audio frequency generator. During the initial connection, you need to set the input signal to about 10 mV. If you need to know the gain, you will need to use the output voltage. To select the average ratio between low and high frequencies, it is necessary to select the capacitance of the capacitor.
You can see a photo of a Hi-End tube amplifier below. For this model, 2 lamps with an octal base were used. A double triode is connected to the input, which is connected in parallel. The final stage for this model is assembled on a 6P13S beam tetrode. This element has a built-in triode, which allows you to get good sound.
To configure and check the functionality of the assembled device, you must use a multimeter. If you want to get more accurate values, you should use a sound generator with an oscilloscope. When you have taken the appropriate devices, you can proceed to setup. At cathode L1 we indicate a voltage of about 1.4 Volts; this can be done if you use resistor R3. The output lamp current must be specified as 60 mA. To make resistor R8, you need to install a pair of MLT-2 resistors in parallel. You can use other resistors of different types. It should be noted that a rather important component is the decoupling capacitor C3. It was not in vain that it was mentioned, since this capacitor has a strong influence on the sound of the device. Therefore, it is better to use a proprietary radio element. Other elements C5 and C6 are film capacitors. They allow you to increase the quality of transmission of various frequencies.
A power supply built on the 5Ts3S kenotron is worth finding. It complies with all the rules for constructing the device. A homemade Hi-End tube power amplifier will have high-quality sound if you find this element. Of course, otherwise it is worth looking for an alternative. In this case you can use 2 diodes.
For a Hi-End tube amplifier, you can use the appropriate transformer, which was used in old tube technology.
To make a Hi-End tube amplifier with your own hands, you need to perform all the steps consistently and carefully. First, connect the power supply with the amplifier. If you configure these devices correctly, you can install a pre-amplifier. Also, using the appropriate technology, you can check all the elements to prevent damage. After assembling all the elements together, you can begin to design the device. Plywood may work well for the body. To create a standard model, it is necessary to place radio tubes and transformers on top, and regulators can already be mounted on the front wall. Using them you can enhance the tone and see the power indicator.
