The design of basic tube power supplies is actually very straight forward. Tone stack for guitar amplifier reference design texas instruments. I intend this article to be a logical consequence of the fine inventions of the 50s and i continue those lines of thought by bringing some new ideas at the end of the millennium. Pdf revisiting the amp that gave solidstate a bad name. A valve amplifier or tube amplifier is a type of electronic amplifier that uses vacuum tubes to. A thermionic valve or vacuum tube contains two or more electrodes suspended inside a glass bulb.
This is demonstrated by the bewildering and illogical variations of valve amp designs including basic circuit design mistakes, particularly with power valve biasing. Any air inside the bulb is thoroughly removed during manufacture, leaving only a. How to build a tube amplifier rob robinettes car and tube. Kuehnel gives you the theory and explains how to use the tools to take control of your tube amp circuits in ways. The overall schema of the power stage, including values of all components, is given in figure 48. May 20, 2010 but many people who make valve amps appear to have a limited and narrow understanding of valve physics when applied in a circuit. For me, the ultrafi was the last piece of the puzzle in my quest to design an ss amp that can rival tube amps.
Design and construction of vacuum tubes amplifier for electric guitar. Twinreverb guitar amplifier in terms if its historic significance, circuit design and. The p1 is a simple tube amp modeled after the classic small guitar amps of the 50s and 60s. The basic theory needed to fully understand the inner workings of a tube amp are explained but the secret sauce is, of course, the online calculators at the publishers website. The choice of a driver tube is the 12ax7 which is a common small signal tube.
Load line analysis was used to determine the behavior of this stage. This is in theory an elegant solution, but unfortunately the extra winding requires space. Some of this material is general and applies as much to hifi circuits as to guitar amps, but some of it is very. Among users of guitar amplifiers there is a tendency of being enthusiastic about the usage of electron. Another useful resource is designing tube preamps for guitar and bass by merlin blencowe. Vacuum tube amplifier distortion guitar amplifiers based on vacuum tube designs have been known to produce a superior sound to solidstate amplifiers.
Verified design tone stack for guitar amplifier reference design ti designs precision circuit description ti designs precision are analog solutions created by tis analog experts. Designing vacuum tube amplifiers and related topics. Reading tube amp schematics by rob robinette the sooner you learn to read amplifier schematics the sooner youll be able to analyze classic amp circuits and learn how the masters of amp design voiced their amps. Designing valve preamps for guitar and bass 2 fig 1. Design my design involves a fourstage preamplifier, which uses two dualtriode 12ax7 tubes. Usually values up to 100k or even more are quiet enough for the second stage grid. Building a brand new valve amplifier using the rh84 design and offtheshelf components. With landmark design work such as the author presents here, the future of the tube amps, which reached their peak around the middle of this century, appears quite strong as we head into a new millennium. A vacuum tube amplifier is a high performance audio amplifier to. It is relatively easy to find introductory information on how to design simple amplifier stages, and it is also fairly easy to find extremely advanced information on complex circuit design, and nearly all of it is.
Design and build your own tube guitar amp guitarsite. Singleended classa tube amplifier aug 10, 2007 2 this configuration serves two major functions. Sep 09, 2017 bg122 a video starting with the basics of reading schematics, slanted towards those involving vacuum tubes. Schematic guitar tube amplifier essentials pdf pages 1 3 text. Lots and lots of helpful people can be found on my amp forum. Our new book applies 21stcentury technology to the design of guitar amplifier preamps, power amps, and power supplies. And amplifier mod merchants lure us over to their benches with svengali promises of sounding like the latest guitar hero. This study includes information of vacuum tubes history and circuit design, theory of ampli. If you are down with bode plots and circuit diagrams, though, it could serve as a nice introduction to building a class ab amplifier. Tube amp schematics, tube amp information, tube amp projects. Excellent internet articles discussing the design of guitar tube amplifiers can be found online e. Elements affecting this sound include the cleverly designed tone stacks, the. Also the inconsistencies between valve amps made it difficult for active systems greater than 2 way, to evolve. Dsp implementation of a 1961 fender champ amplifier by.
Explores all manufacturers and demystifys the inner workings of tube amps. The vacuum tube guitar amplifier still sets the performance standard for the desirable sound of this music production instrument. Its designed to be a managable project for the first time builder while still offering a satisfying result. Basic theory a 21stcentury approach to understanding preamp, power amp, and power supply design fundamentals of guitar amplifier system design a structured methodolody for crafting an awesome guitar amplifier. The slides are pretty heavy on engineering design terms, but give a good feel for what it takes to construct and tune an audio amplifier using vacuum tube technology. Singleended classa tube amplifier design and construction ben verellen, daniel nevistic, and max gorman m. Many different tone stack implementations exist, but this design uses what is known as the fmv tone stack. When purchasing a new valve amp, discerning music lovers would select a new amp from 3 or more of the same model. Following is a list of must have books for the serious tube amplifier designer. Singleended classa tube amplifier design and construction.
Book for musicians, amp builders, and tube audio enthusiasts. There are several theories to explain the tube amplifiers specific, distorted guitar sounds as compared to the solidstate amplifiers sound. Cliff jacks are isolated from the chassis and must be grounded via a ground wire. How to design valve guitar amplifiers the valve wizard.
A vacuum tube amplifier is a high performance audio amplifier to deliver the optimum tone to the listener. Pdf first of three articles discussing the fender solidstate twinreverb guitar. Of course, no lover of tubes should be without the original masterpiece. Sep 01, 2009 written for musicians, amp builders, and tube audio enthusiasts, design and construction of tube guitar amplifiers provides a complete yet easytounderstand explanation of how to design, modify, construct, and test tube amps. Vacuum tube circuit design pdf file 512 pages revered as much as ones guitar, the fender amplifier gets its. Lets start by looking at the simple standard tube amplification circuit that you will see again and again as you study tube amp schematics. Building your own guitar amp is a rewarding pastime, but learning how to do it can be time consuming and frustrating sometimes. A bibliography of must have tube electronics books.
We will assess the amplifier condition original caps, original 2prong power cord, crusty looking transformer. Rca receiving tube manual, radio corporation of america. Guitar signal shown in pink enters the tube on the left at ac signal in. Some of them are long out of print, and can only be obtained from used book sellers, although they are occasionally seen for sale on the internet.
And, if we rely on the excellent work of those whove come before us o. Covers how tubes work and how to design circuits around them, with chapters on class aab1 and ab2b amplifier design, power supplies, and more. Tons of empirical data that demystify the 519 pages tube pdf file guitar amplifier power amps. The idea with the butterfly nut is not bad since in theory it would be. Design and construction of tube guitar amplifiers by robert megantz this is a great book to get involved in the theory of amplifiers. Detailed, complete with plenty of math and drawings. The importance of an amplifier s input and output impedance is discussed in ac theory module 7, and using nfb to control impedance is described in amplifiers module 3. However, vacuum tubes are still commonly used in guitar amplifiers. Twinreverb guitar amplifier in terms if its historic significance, circuit design. Real time tube guitar amplifier simulation using webaudio. This module shows how to simply calculate the values needed to make a working amplifier that has. We adopt a pushpull configuration in ultralinear mode.
If your amp doesnt make guitar sounds at startup check those first. Another good one that is fenderfocused is dave funks tube amp workbook. The first tube amplifiers were constructed with triodes, directly coupled to high impedance loudspeakers. Ill have a sound clip of my current amp design project, an ultrafi ss guitar amp that sounds pretty amazing. Once the dspbased design is completed for this small amplifier, the algorithm can be reconfigured for other vintage vacuum tube amplifiers. Many amps of the same model could vary considerably. Heyboer told me these will handle 144ma full duty and probably a bit more for audio duty. Abstract compared, guitar in hands, the different simulations in terms of this paper presents a tube guitar amplifier simulation made with the webaudio api, that reproduces the main parts of the marshall jcm 800 amplifier schematics. Youll want to take notes as you read, but its written with musicians in mind. We figured these are good for about 20 watts single ended. This the first video of many on design and build of an audio tube amp. The most popular jazz guitar amps top 25 survey results. Although oriented towards valve guitar amplifiers, ax84s free schematics and theory document. Design of the driver stage is concerned with voltage amplification as well as linearity in order to provide the output section with a strong and relatively clean signal.
An easily constructed highquality singleended 8w amplifier. How guitar amps work and what you can do to start tweaking. Btw, hopefully by the end of this year, ill have a sound clip of my current amp design project, an ultrafi ss guitar amp that sounds pretty amazing. In preamp stages, the plate resistor determines the loadline slope. In some short circuit conditions this might lead to lethal accidents. Fleming used the principle to design the diode, the first vacuum tube patented in 1904. In the center of a tube s glass envelope is a cathode. Aug 10, 2018 the basic theory needed to fully understand the inner workings of a tube amp are explained but the secret sauce is, of course, the online calculators at the publishers website. Some have exceptional ideas, while others just add a 12ax7 to the input of your marshall. Inside fender and marshall tube amps pdf viva analog. Covers all the essential of tube electronics design, including the basics, tube theory, load lines, amplifier design, etc. Each stage of the real amp has been recreated preamp, tone stack, reverb, power amp and speaker.
Kuehnel gives you the theory and explains how to use the tools to take control of your tube amp circuits in ways that may surprise you. Electron vacuum tube guitar amplifier semantic scholar. It carries just a slight positive charge, and its ready to release a gazillion electrons. The theory behind the operation of a vacuum tube is based on a concept known as thermionic emission. The two most common assembly mistakes are miswired input and speaker jacks. Vacuum tube guitar amplifier rutgers university, electrical.
Fundamentals of amplification this chapter deals with the design and analysis of the basic triode gain stage, which is the main building block of a valve preamp. Schematic guitar tube amplifier essentials pdf only pedal or amp that can introduce cut and real tube boost to those critical frequencies. I started out with the previously mentioned dave hunter bookthe guitar amp handbookas well as tom mitchells how to service your own tube amp. A theoretical transistor 5 is presented in 1948 by a group of scientists at. For me, the ultrafi was the last piece of the puzzle in my quest to design an ss amp. I used them on all kinds of amps from little bitty things up to kt88 and they rocked.
More electron tubes can be found in the tube store collection of new old stock nos if you are looking for a tube shop carrying the very best tubes for your amplifier, youve come to the right place. My tube amplifier and guitar help forum amplifier service technicians listing tube amp schematics and layout diagrams everything from acoustic to wurlitzer pdf tube amp. Attached please find a table of contents for this class. If youre interested in understanding, designing, or building greatsounding amplifiers and speaker systems, design and construction of tube guitar amplifiers and design and construction of guitar and bass speaker systems contain the information you need. Beginning with the ku models in 1945, which were all tubes, and launching a solid state amp line in the late 60s, fender amps have long been a staple choice for guitarists of any genre, including jazz. In this vid, well begin service on an early 60s vintage ampeg rocket 112 combo. Introduced by fender in 1957 in the 5f6 bassman, it was later copied by marshall, vox, and many other guitar amplifier manufacturers 2. The spreadsheets generated for use with this book are specific to the manual. If your amp has problems see the tube amp troubleshooting guide. Class b are pushpull amplifiers, similar to conventional solid state amplifiers, where there is a pushing tube and a pulling tube being driven 180 deg out of phase. Ax84 p1 tube guitar amplifier project classic projects current version testing version old versions overview. The power amplifier involves three stages, two of which use a 12ax7. The first and second stage tube s should be selected for low hum and microphonics. Complete guide to vintage tube amplifiers volume 1 fender.
There are also many books on the subject of tube amp circuit theory, design and building that you can read to help make your first build of boutique quality. Understanding vacuum tube amplifier schematics basics. Low voltage vacuum tube pre amplifier for guitar from user needs to a commercialized product eric nolan sporer department of product and production development chalmers university of technology summary the vacuum tube was the first electrical signal. Written for musicians, amp builders, and tube audio enthusiasts, design and construction of tube guitar amplifiers provides a complete yet easytounderstand explanation of how to design, modify, construct, and test tube amps. Dsp implementation of a 1961 fender champ amplifier by james. Computerbased visualization replaces the traditional litany of mathematical formulas. The guitar signal flows through the grid stopper resistor to the tube s grid, then out the tube. If you arent sure about which valve you need, or what tubes you can substitute, let us help you. Fortunately, solidstate and tube amplifier circuits share a lot of similarities. Most of the boutique amps being made today are cloned vintage fender and marshall amps or at least heavily influenced by their circuits. A number of recent visitors have registered surprise that we do not have any music playing in our workshop.
Mar 18, 2019 in this vid, well begin service on an early 60s vintage ampeg rocket 112 combo. Audio transformer design for tube amplifier with improved quality and reduced cost project team. Reich, we dont even need to tackle any advanced math or taxing mental gyrations to arrive at. Design and construction of vacuum tubes amplifier for. Output transformers dramatically increase the cost of a valve amplifier circuit. Since tube guitar amplifiers are the easiest thing in the world to play with, many gurus have come out of the woodwork. Jan 17, 2017 plus, working on your amp when something is wrong can be both fun and rewarding, not to mention possibly essential if youre on the road and in need of a quick fix.
Jul 15, 20 the tube used in that case was the cathode ray tube aka crtbetter known today as an old, prelcdledplasma television. Most of these free music theory lessons contain a free pdf download that contains the actual tutorial. The science of electric guitars and guitar electronics. Class ab amplifiers are the most common in larger guitar amplifiers because of their efficiency. Ultralinear mode and pushpull configurations were introduced respectively in section 2. Resistor noise doesnt factor in much in stages after that. Any air inside the bulb is thoroughly removed during manufacture, leaving only a vacuum. So heres a basic overview of how amps work and what you can do to start tweaking your own.
It is intended as a companion to design and construction of guitar and bass speaker systems. Profusely illustrated, the book uses graphic aides and basic algebra. Keep those filaments lit, design your own vacuum tube. Without going into the theory of these devices, it is adequate to state. If youre here then youre probably thinking about tinkering inside one. In addition to this concepts including the attraction and repulsion of opposite and like charges play a large part in the operation of vacuum tubes thermionic valves. There are a number of classes and variants of tube audio power amplifiers. A tube amplifier has an inherent peaktopeak asymmetry, which can be lessened or increased by varying the slope of the loadline. Coates 2007 2012 class a amplifier design introduction to amplifier design basic design process. Fleming used the principle to design the diode, the first vacuum tube. An easily constructed highquality singleended 8w amplifier using standard valves and the. In guitar amps, were not that interested in displaying images with our tubes, but were still very interested in controlling those electronsand we can use a guitar to do it. The p1ex amplifier is a simple threestage vacuum tube electric guitar amplifier. Eventually you may want to create a power amplifier.