The wattage output in an amplifier may vary from application to application due to many variables such as tube types, solid state vs. You can also measure the actual plate current by shunting the output transformer with a multimeter in the dc milliamps mode and use the tube dissipation using plate current calculator. Download transformer calculator coils and wire thickness at. Minimum inductance of the primary winding of output transformer. If you have some experience in assembling transformers, then this program is perfect for you. You know you would like to match this impedance to loads of 8 and 4 ohms, and this will be used for. A 3 phase transformer has three magnetic circuits that are interlaced to give a uniform distribution of the. Transformer calculation software electronic circuits. There are more tube amplifiers such as singleended, pullpush, high power, and wireless bluetooth tube amplifier. Audio transformer and impedance matching transformer. Most of the model differentiation comes from the power supply, the number of preamp stages, fx, power tube type and number, output transformer and speaker configuration. Transformer calculator kva calculator full load amps calculator.
E design opt for 1 x el34 pentode with or without cfb. Designed specially for mot microwave oven transformers but this calculator will work for any transformer. To separate the high voltage and match the speaker impendance with the tube impendance we need audio grade output transformer. You measure the output transformer s voltage drop and resistance to calculate the bias current. In contrast, the larger bassmansuper reverb trannies will relate the vacuum tube and circuits clipping before the tranny hits the ceiling, which accounts for the fast, grainy. Artists later took advantage of this saturation for that tube sound along with higher than normal plate voltages pushing the maximums for more power from a small container. The following guidelines should be taken into account. There are more output transformers for tube amplifier, you can get your wanted from them. This is necessary to get an efficient transfer of the audio signal to the speaker. This transformer calculator helps you to quickly and easily calculate the primary and secondary fullload currents of the transformer. Looking through all of my scavenged transformers i cant find a single one in the thousands of ohms, most are a few hundred and lower. This tranny has pc style mounting pins but you can also solder wires to the pins for non pc hookups.
Donwload transformer calculator program for calculating number of coils and wire. Calculating output transformer impedance sarris custom. Understanding your output transformer part one by mark. Audio output transformers are heavily used in a vacuum tube and some. For homebrew projects, the best option is to construct those transformers by ourselves and this script helps to calculate winding parameters for those. Optional rload in ohms typically the output transformer primary impedance only considered when pp pushpull is selected number. Tube bias calculator rob robinettes car and tube amp. Determination of power and energy losses in power transformers.
The objective of this project is to develop an output transformer for singleended tube amplifiers with. Table 2 gives parameters for the pat4006cfb output transformer relevant to spice simulation. Professionals with experience in transformer assemblies use the computer program to calculate the number of coils and wire thickness. Output trannys contribute most of the distortion in a valve amp and have a limited bandwidth. Tcj pushpull calculator is a 32bit program that runs under windows 9xntme2000xp. The halfprimaries of the output transformer should have identical voltages on them. Feb 02, 2017 the peavey butcher has 4 speaker jacks. Apr 30, 2010 the output transformer is the heart of a valve amplifier. Youre right, the 5f1 output transformer is under rated mostly for cost saving. Sep 27, 2014 tcj pushpull calculator has but a single purpose. Tubes do not affect impenitence, speaker load does. If you download tube data sheets for 6l6gc and 6v6gt tubes ge, sylvania, or rca data sheets are my favorites and look at the recommended operation conditions supplied by the orig tube engineersyoull find that there is a range of platetoplate loads aka ot primary impedance into which these tubes will safely operate. Single ended output transformer calculating spreadsheet with. Secondaries should have multiples of the voltage youre putting on the tap you chose.
If you have an 8 ohm output transformer hooked up to an 8 ohm speaker, the transformer is seeing what it is looking for, if you hook the same transformer to a 16 ohm speaker it will have a 16 ohms load, the transformer is. Use the ac wall wart below to power this transformer. The tube bias calculator will calculate power tube bias values of plate current, dissipation and % of max dissipation using either measured voltage drop. An online three phase transformer calculator to find the current in different power units.
Dec 02, 2015 designed specially for mot microwave oven transformers but this calculator will work for any transformer. If you need a really simple way to calculate both power mains transformers and audio transformers be it a pushpull or single ended ones mainly for tube. There are several things that are important in getting an output transformer made. Then i cover the different speaker combinations and. Toroid transformers ring profile of core and others arent supported. Audiophile tube output transformers whether you are into the clean, free spirited single ended tube output or high efficiency, high power, pushpull audio, we have the output transformer for you. Output transformers made in usa triode usa tube amp kits. Pushpull output transformer spreadsheet calculator with. Tube bias calculator for android free download and software.
The free shipping option allows tubedepot to choose the most appropriate carrier and service. It also determines the turns ratio and type of transformer. Delatschtransformercalculator for ios free download and. I just got this response when i asked someone about swapping 6v6 and 6l6 power tubes. If this is true, what is the nature of this concept.
The two output trannys are rotated 90deg to the power mains tranny to avoid picking up induced hum from the mains tranny external magnetic field. To design an output transformer, it is necessary to determine the output power according to the tubess characteristics. Optional rload in ohms typically the output transformer primary impedance only considered when pp pushpull is selected number of tubes power tubes pre amp tubes. Calculation of output transformers the output transformer is probably the most expensive part in the amplifier and something you have to live with if you like classic tube amplification. Vacuum tube calculators basic theory using 21stcentury technology to design vacuum tube preamps, power amps, and power supplies system design a professional methodology for crafting a complete guitar amplifier. All are of different design and concept and quality. Working with tube amps you may need to calculate the output transformer impedance especially when we have an old transformer or a transformer with unknown values. Understanding your output transformer part one by mark baier.
From the tube data books, you determine that a pair of 6l6s. Tube bias calculator rob robinettes car and tube amp website. The pat4006cfb is a semicustom version of the 100w pat4006, available on special order, designed for four 6550 or similar tubes in pushpullparallel. Tube amp transformers tube amp parts, guitar amp parts. Are you looking for the best transformer calculator software for your next project.
Amps that use this smaller 28watt transformer are always going to have that certain compression and dynamic that defines an output transformer going into saturation. Select the number of phases from the dropdown menu. To calculate bias when you measure the plate current, such as when using the output transformer shunt current measurement, enter your tube type and platetocathode voltage at the top of the page. Aug 25, 2015 audio output transformers are heavily used in a vacuum tube and some older transistor base audio power amplifiers, but these days output transformer are quite hard to find and expensive item. Nov 18, 20 amps that use this smaller 28watt transformer are always going to have that certain compression and dynamic that defines an output transformer going into saturation. Enter the transformer rating and select the appropriate unit. If you used an 8 ohm tap, a 4 ohm tap will have about 2. Universal output transformer wiring antique radio forums.
Tamura corporation audio transformers for tube amp. When you begin the calculation you have to select the respective. How to calculate audio output transformer load resistance. We have been producing tube output transformers continuously for over 75 years. It has two types, single phase and three phase transformer. Turns ratio v in to the primary v out measured in the secondary e. I volunteered to put a 4 ohm load on my amplifier and re run the tests. As an example, you might want to design an output transformer for a single pair of 6l6 output tubes. Transformer calculator kva calculator full load amps. Tcj pushpull calculator helps tube audio amplifier designers develop pushpull output stages that yield low distortion and long tube life. If you would like to simply calculate number of turns and other aspects of your output transformer for a pushpull tube guitar amp or a home hifi tube amp, dont miss out on this tried and tested method which is an easy to use excel spreadsheet that automatically calculates the transformer windings according to your needs. Single ended output transformer calculating spreadsheet.
The lowly ab763 blackface deluxe has anemic power and output transformers, two preamp stages, two small power tubes and a single 12 inch speaker driven by 22 watts. If you need assistance with circuit protection devices such as fuses or breakers, or wire sizing, please consult a licensed electrical contractor or electrician in your area who will be familiar with state and local codes. You measure the output transformers voltage drop and resistance to calculate the bias current. This is shown in the example with 3 different circuits.
Use the following instructions to determine the load resistance of an unknown audio output transformer. Tube bias calculator for android free download and. Ab763 blackface amp model differences rob robinette. Transformer capacity calculator three phase transformer. To increasedecrease the alternating volts in electric power, transformers are used. Ttgcfb5000pp tube output cfb transformer 5kohm cathode feedback pushpull 474,00 zl threephase transformer t3s 2500va 3x400v 3x230v 1 890,00 zl shop is in view mode. I cover how to calculate the reflected impedance of the output transformer secondary onto the primary. Pushpull output transformer spreadsheet calculator with pdf. Iif you would like to calculate and wind your own single ended and push pull output transformers for guitar amps and home hifi amplifiers, ive. Hybrid transformer are ordinarily small and under high load it can overheat. To calculate bias when you measure the plate current, such as when using the output transformer shunt current measurement, enter your tube type and. He wrote over 360 articles for various dutch high end audio magazines and is the author of the book transformers and tubes. The output transformer is the heart of a valve amplifier.
The cost of a tube amplifier mostly consists of the cost of an output transformer and tubes that is usually a factor limiting the sound quality. All we have to do is to calculate the turns ratio of the transformer. For single ended amplifiers with opt idc flow in one direction only. The function of the audio output transformer is to transform the high impedance of the output tube to match the much lower impedance of the speaker. The one thing im stuck on is the output transformer, according to the datasheet i need to get a 35004000 ohm transformer with a 4 ohm output to power a car speaker i have. Results of his output transformer research were published at aes conventions in 1994 and 1998. Building a tube amp, how to calculate output transformer. If you would like to simply calculate number of turns and other aspects of your output transformer for a single ended tube guitar amp or a hifi home tube amp, dont miss out on this tried and tested method which is an easy to use excel spreadsheet which automatically calculates a transformer according to your needs. Calculating output transformer impedance sarris custom tube. Next, measure the voltage across the speaker taps with a. Electronics projects, electrical engineering, vacuum tube, ham radio. How to calculate the output transformer impedance of an opt with unknown values. This is practically the determination of the output impedance of a circuit by means of the dc transfer function. Audio transformer is the primary part of a tube amplifier which generates an electromagnetic field.
Voltage design is made for wide applications for use in combination with various kinds of vacuum tubes. We have been producing tube output transformers continuously for over 75 years, constantly improving and tweaking their performance. The disadvantage is that the a2 triode requires the cost of an extra tube, and the output tube grid can overheat, so a2 is in. Audio output transformers are heavily used in a vacuum tube and some older transistor base audio power amplifiers, but these days output transformer are quite hard to find and expensive item. It was suggested that you could put an 8 ohm load on a 16 ohm 5k primary transformer to get a 2. Output transformers made in usa triode usa tube amp. Output transformer efficiency usually in the range from 0.
Output audio transformer design the output transformer in a singleended tube amplifier is the device which matches the high output impedance of the tube to the low input impedance of the speaker load 4, 8 or 16 ohm. The formula calculates the frequency response based on the triodes amplification factor and plate resistance. Whether you are into the clean, free spirited single ended tube output or high efficiency, high power, pushpull audio, we have the output transformer for you. Langfordsmith, editor, radiotron designers handbook, 4th edition, harrison. Transformer winding turns and voltage ratio calculatorv1, n1, v2, n2.
Classic tube output audio transformer overview hammond mfg. Maximum leakage inductance of the primary winding of output transformer. It is important to note, however, that these solutions are best only for those experts who have knowledge and experience with assembly transformers. The pentode equation differs from the triode equation in that the screen grid replaces the plate as a controlling element, and an arctangent term from scott. If the output impedance of the amplifier is 120 calculate the nominal impedance of the loudspeaker required for maximum power transfer. If you dont known anything about assembling transformers, please dont use calculations from this program for building your own transformer. From the tube data books, you determine that a pair of 6l6s will put 4050w in class ab push pull into a 4400 ohm plate to plate impedance. This program can calculate values only for standart transformer core, thats w and u profile of core. So we apply an ac voltage to the primary of the transformer and we measure the output voltage to the secondary. The output transformer as an impedance matching device, works on the principal of reflected load. This method is more dangerous because when your meter probe. Get a low voltage ac transformer about 10v or less and place it across the speaker taps of the output transformer ot.
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