Search results for "amplifier"

From SRPP and Mu-Follower to OTL Designs Tube amplifiers suffer from distortion. Fortunately, circuits such as the SRPP amplifier, mu-follower, and beta-follower produce minimal distortion even at output voltages of 50 to 100 Vpeak. These designs are often published with errors. Without a sound understanding of the theory, it is easy to arrive at a flawed design. In the first section of this book, we investigate the origin of distortion, while in the second we investigate the design of and SRPP and a mu-follower. On the internet we can find the most exotic designs. Evaluating them teaches us that these designs often make matters worse rather than better. In the chapter on incorrect SRPPs and mu-followers, we sometimes see bizarre and misguided designs where using a simple single-triode amplifier would perform much better. Push-pull output stages also exist. A great number of them are examined, and their similarity to the SRPP is discussed. This is done especially with the help of the theory behind the OTL based on the ‘mother’ of all OTLs, the Philips HF303. Finally, attention is given to frequency characteristics and technical matters such as the supply voltage and the filament power supply. To illustrate these points, there are a few designs covering the subjects discussed. This book presents much new theory that has not been published before. It is often an eye-opener, showing that many things have a beautiful and unexpected simplicity.

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A Toolbox for Audio Lovers and Engineers Without any ambition to reach scientific levels, this book aims to be a toolbox for both audio lovers and high-end equipment designers. The elementary theory presented is the bare minimum for readers to grasp the operation and practical use of electrical, electromagnetic, physics, and electronic operations available in the designers’ toolbox. Each tool is explained in a minimum of words and theory without needless coverage of underlying equations or figures. The book chapters guide you through the process of designing quality amplifiers with vacuum tubes, from the very beginning, considering both technical and subjective requirements – in theory and practice. The book is a compilation of the author’s notes used in his professional and educational career but was nevertheless primarily written as a result of true love for the audiophile hobby.

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From SRPP and Mu-Follower to OTL Designs Tube amplifiers suffer from distortion. Fortunately, circuits such as the SRPP amplifier, mu-follower, and beta-follower produce minimal distortion even at output voltages of 50 to 100 Vpeak. These designs are often published with errors. Without a sound understanding of the theory, it is easy to arrive at a flawed design. In the first section of this book, we investigate the origin of distortion, while in the second we investigate the design of and SRPP and a mu-follower. On the internet we can find the most exotic designs. Evaluating them teaches us that these designs often make matters worse rather than better. In the chapter on incorrect SRPPs and mu-followers, we sometimes see bizarre and misguided designs where using a simple single-triode amplifier would perform much better. Push-pull output stages also exist. A great number of them are examined, and their similarity to the SRPP is discussed. This is done especially with the help of the theory behind the OTL based on the ‘mother’ of all OTLs, the Philips HF303. Finally, attention is given to frequency characteristics and technical matters such as the supply voltage and the filament power supply. To illustrate these points, there are a few designs covering the subjects discussed. This book presents much new theory that has not been published before. It is often an eye-opener, showing that many things have a beautiful and unexpected simplicity.

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The Elektor Low-Noise Lab Power Supply is a fully analogue, adjustable, medium-power symmetrical bench supply that contains no switching or digital components. It provides an output voltage adjustable between 0 V and ±22 V, and an output current adjustable from 0 A to 1 A. Because it avoids any form of switching circuitry, the design delivers extremely low noise. To display both output voltages and currents, four miniature moving-coil panel meters are used. Most modern laboratory power supplies and AC adapters employ switch-mode techniques. Even the best examples inevitably exhibit high-frequency ripple and other switching artefacts on their output, which can interfere with the testing of sensitive analogue circuits and disturb low-level measurements. To overcome this, the concept here is a completely analogue power supply. Although less efficient than its switch-mode counterparts, the reduced efficiency is of little importance for test-bench use and ensures cleaner, more reliable measurement results. Because many analogue circuits require a symmetrical supply, this design delivers positive and negative output voltages of equal magnitude. A small amount of adjustment is available to compensate for any imbalance. Naturally, a variable current-limit function is also included. The kit includes the components required to build the power supply, except for the transformers. Specifications Output Voltage 0…+22 V, 0, −22 V Output Current 0…+1 A, 0…−1 A Noise −85 dBV, (at 0.95 A/20 V, B = 22 kHz) −84 dBV (at 0.95 A/20 V, B > 500 kHz) Ripple 50 µVRMS (at 950 mA/20 V, B = 22 kHz, mainly 100 Hz component) Included 3x PCBs: Regulator (PCB-1), Mains Filter (PCB-2) and Transformer (PCB-3) All the components except the AC transformers 4x moving-coil meters Additional parts for wiring (wires, banana sockets, IEC Power entry module, etc.) Not included The three AC transformers An enclosure Parts List For the Regulator PCB (240386-1) Resistors (250 mW, 1%) R1 = 12 Ω R2, R8, R37, R62 = 1 MΩ R3, R7, R10, R13, R17, R20, R22, R30, R35, R42, R45, R47, R55, R60 = 100 Ω, 600 mW R4, R5 = 4.7 kΩ R6 = 100 kΩ R9, R12, R14, R36, R38, R39, R61, R63, R66, R72, R78, R79 = 10.0 kΩ, 600 mW R11 = 9.76 kΩ, 600 mW R15, R40 = 44.2 kΩ, 600 mW R16, R41, R77 = 1 kΩ R18, R43 = 1.5 kΩ, 1 W, 5% R19, R44 = 470 Ω, 1 W, 5% R21, R46 = 330 Ω, 600 mW R23, R24, R48, R49 = 1.0 Ω, 1 W R25, R50 = 1 kΩ, 1 W, 5% R26, R28, R51, R53 = 1.000 kΩ 0.1%, 15 ppm/C R27, R29, R52, R54 = 10.00 kΩ 0.1%, 15 ppm/C R31, R56 = 1.2 kΩ, 1 W, 5% R32, R57 = 47 kΩ R33, R58 = 270 Ω R34, R59 = 27 kΩ R64, R69 = 12.0 kΩ R65 = 3.0 kΩ, 600 mW R67, R80 = 470 Ω, 600 mW R68, R70 = 6.8 kΩ, 600 mW R71 = 30.0 kΩ,, 600 mW R73, R74, R75, R76 = 10 MΩ P1, P2, P3 = 10 kΩ, 200 mW, 20%, potentiometer, 1 turns, single, lin., panel mount P4, P5 = 500 Ω, 500 mW, 10%, trimmer, 25 turns, 3296Y-1-501LF Bourns P6, P7 = 10 kΩ, 500 mW, 10%, trimmer, 25 turns, 3296Y-1-501LF Bourns Capacitors C1 = 100 nF, 50 V, 10%, ceramic X7R, LS 5 mm C2, C3, C6, C7, C30 = 10 µF, 63V, 20%, LS 2.5 mm, 3000hours@105°C C4, C5, C8, C9, C13, C14, C18, C19, C23, C24, C28, C29, C31, C32, C38, C39 = 100 nF, 250 V, 10%, PET, LS 7.5 mm C10, C20 = 47 nF, 100 V, 5%, PET, LS 5 mm C11, C21 = 10 nF, 100 V, 5%, PET, LS 5 mm C12, C22 = 220 µF, 35 V, 20%, 0.024 Ω, LS2.5/3.5 mm, Ir 3.4 A, 2000hours@125°C, polymer C15, C25 = 120 µF, 50 V, 20%, ESR 0.02 Ω, Diam. 10 mm max., LS 5 mm C16, C26 = 15 nF, 100 V, 5%, PET, LS 5 mm C17, C27 = 47 nF, 100 V, 5%, PET, LS 5 mm C33, C34 = 22 µF, 50 V, 20%, LS 2 mm, 10000 hours @ 105°C C35, C36, C44, C45 = 1 µF, 100 V, 10%, LS 5 mm, ceramic X7R C37 = 100 uF, 50 V, 20%. LS 3.5 mm C40, C41, C42, C43, C46, C47, C48, C49 = 1000 µF, 50 V, 20%, LS 5/7.5 mm, Ir 3.32 A, 10000hours@105°C, D 16 mm C50, C51, C52, C53 = 47 nF, 100 V, 10%, ceramic X7R, LS 5 mm Inductors L1, L2 = 4.7 µH, 3.2 A, 0.033 Ω, LS 5 mm, RLB0914-4R7ML Bourns L3 = Commom mode choke, 14.5 mH, 3 A, SSRH24NH-30145 Kemet Semiconductors D1, D2, D3, D4, D5, D9, D10, D11, D15 = BAT85, DO-34 D6, D7, D12, D13 = SR560, DO-201AD D8, D14, D16 = 1N4148, DO-35 D17 = Zenerdiode, 5.6 V, 0.5 W, DO-41 D18, D19 = 1N4004, DO-41 D20, D21 D22, D23 = V30100CI-M3/P, dual common cathode, TO-220 D24 = Zener diode, 30 V, 1 W, DO-41 LED1, LED2 = LED, red, T-1 (3 mm) LED3, LED4 = LED, green, T-1 (3 mm) TVS1, TVS2 = BZW50-33B, R6 T1, T2, T4 = BC337.25, TO-92 T3 = NJW0302G, TO-3P T5, T6, T8 = BC327.25, TO-92 T7 = NJW0281G, TO-3P T9 = BD139, TO-126 (SOT-32) IC1 = LM334Z, TO-92 IC2 = LM4040AIZ-5.0/NOPB, TO-92 (TO-226AA-3) IC3, IC4 = OPA2992IDR, SOIC-8 IC5, IC6 = OPA4992IDR, SOIC-14 IC7 = OPA992IDBVR, SOT-23-5 IC8 = LM339N, DIP-14 IC9 = LM317, TO-220 IC10 = LM337, TO-220 Others F1, F2 = 5×20 mm fuse, 1.6 A, fast acting HS1, HS2 = Heatsink MC33271 (for T3/T7), 2.7°C/W, PCB mount, height 63.5 mm K1, K4 = 3-way screw terminal block, LS 3.5 mm, max. 1.5 mm² K2, K3 = 3-way screw terminal block, LS 3.5 mm, max. 1 mm² M1, M3 = Moving coil meter, Range 30 V, type 91C4, 45×45 mm M2, M4 = Moving coil meter, Range 1 A, type 91C4, 45×45 mm² RE1 = Relay DPDT,5V, UA2-5NU Miscellaneous 3× 3-way screw terminal block, LS 3.5 mm, max. 1 mm² (for P1, P2, P3) 4× Pin header, 1×2, vertical, pitch 2.54 mm (for LED1, LED2, LED3, LED4) 4× Pin socket, 1×2, vertical. pitch 2.54 mm (for LED1, LED2, LED3, LED4) 2× Heatsink FK222SA220, 20°C/W, PCB mount (for IC9 & IC10) 2× Mica thermal pad for TO-220, 12×18×0.05 mm (for IC9 & IC10) 2× Insulating bushing IB 6, TO-220 (for IC9 & IC10) 2× Ceramic thermal pad, 23×20×2 mm (for T3 & T7) 2× PCB Fuse Holder, for 5×20 mm fuse, 10 A (for F1, F2) 2× Cover for PCB Fuse Holder, transparent (for F1, F2) 2× 2-way screw terminal block, LS 3.5 mm, max. 1 mm² (for M1 & M3) 2× 2-way screw terminal block, LS 3.5 mm, max. 1.5 mm² (for M2 & M4) 8× M3 solder lug, thickness 0.35 mm (for M1…M4) M4 solder lug, thickness 0.35 mm (to connect 4 mm banana connectors) Screened cable, 1 pair, 2×24 AWG/0.22 mm², 1 m (for P1, P2 & P3) IC socket, DIP, 14 contacts (for IC8) M3 washer, plain, steel M3 screw, 16 mm, steel, pan head M3 nut M3 spring washer 50 mm M3 standoff, steel, male-female 12 mm M3 standoff, steel, male-female 10 mm M3 standoff, steel, male-female M3 screw, 8 mm, steel, pan head For the Mains Fiter PCB (240386-2) Resistor R1 = 220 kΩ, 1 W, 500 V, 5% Capacitors C1, C2 = 470 nF, 305 VAC, Class X2, 11 × 27 mm max., LS 15/22.5 mm C3, C4, C5, C6 = 2.2 nF, 300 VAC, Class Y2, 13 × 4 mm, LS 10 mm, PP Inductors L1, L2 = Common-mode choke, 6.8 mH, 1.7 A, TDK B82732R2172B030 Semiconductor MOV1 = TVS varistor, 300 VAC, S14K300 (230 VAC, B72214S0301K101) and SK14K150 (150 VAC, B72214S0151K101) Others K1, K2 = 3-way screw terminal block, LS 7.62 mm F1 = Time-delay fuse, 0.5 A (230 VAC) or 1 A (115 VAC) Miscellaneous 1× Fuse holder, 5×20 mm, 10 A, 500 VAC 1× Transparent fuse cover 4× 10 mm M3 standoff, steel, male–female 4× M3 screw, 8 mm, steel, pan head 4× M3 nut For the Transformer PCB (240386-3) Resistors R1, R2 = 2.7 kΩ, 600 mW, 1% R3 = 10.0 kΩ, 600 mW, 1% Capacitor C1 = 220 µF, 50 V, 20%, Ø10 mm, LS 5 mm, 4000 h @ 105°C Transformers (not included in this kit!) TR1, TR2, TR3 = 2×7 V, 25 VA, PCB-mounted toroid, 70060K Talema Semiconductors D1–D4 = 1N4148, DO-35 D5, D6 = 1N4004, DO-41 D7 = Zener 5.6 V, 1.3 W, DO-41 LED1 = LED, red, T-1 (3 mm) IC1, IC2 = MOC8021M, CTR ≥ 1000%, DIP-6 Others F1, F2, F3 = 160 mA time-delay fuse (230 VAC) or 315 mA time-delay fuse (115 VAC) K1 = 2-way screw terminal block, LS 7.62 mm K2 = 3-way screw terminal block, LS 3.5 mm, max 1.5 mm² K3, K4 = 3-way screw terminal block, LS 3.5 mm, max 1 mm² RE1, RE2 = Relay DPDT, 5 A/250 VAC / 24 VDC Miscellaneaous 1× Pin header 1×2, pitch 2.54 mm + matching socket for LED1 3× Fuse holder 5 × 20 mm, 10 A, 500 VAC + transparent cover 3× M4 screw, 8 mm, pan head + washer for TR1-TR3 8× M3 screw, 8 mm, pan head + nut + washer 8× 10 mm M3 standoff, steel, male–female 2× IC socket, DIP-6 for IC1 & IC2 Additional Parts 1 m red insulated wire, stranded, 1.5 mm² 0.5 m blue insulated wire, stranded, 1.5 mm² 0.5 m black insulated wire, stranded, 1.5 mm², 0.5 m 2 m red insulated wire, stranded, D 0.56 mm (0.25 mm²) 2 m black insulated wire, stranded, D 0.56 mm (0.25 mm²) 0.5 m Multicore Cable, Flexible, 3 Core, 0.75 mm² (24 x 0.2 mm) Red banana socket Black banana socket Blue banana socket Green banana socket IEC Power Entry Module with switch, IEC C14 3 crimp terminals, FASTON, 4.75 x 0.81 mm 3 knobs Links Elektor Labs JumpStarter Page Article (Part 1) Article (Part 2)

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Jan Didden created Linear Audio in 2010 and published 14 Volumes between 2010 and 2017. Each 200-page Volume contains on average 10 articles by expert authors in the field of audio, acoustics, and instrumentation. Whether you are interested in tube amplifiers, solid-state equipment, loudspeaker design, capacitor and resistor distortion or distortion measurement, you are certain to find helpful advice and interesting discussions. From beginner to advanced level, for the audio professional or the serious hobbyist, this ExpertCollection will advance your understanding and offer new perspectives on common issues. Bonus material included with this collection is a 5-part YouTube series on negative feedback as applied to audio by renowned author Jan Didden, and nine additional landmark audio articles and presentations. If you are seriously interested in audio, acoustics, and instrumentation, you can’t afford to miss this! The published material is indexed and fully searchable and will provide an almost limitless resource for many years to come. You can read about Linear Audio’s authors, and the Table of Contents of each Volume, at linearaudio.net.

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Nobody has any doubt that valve amplifiers produce a remarkably beautiful sound. They have a lively, deep, clear, and expressive sound, and dynamically they do not appear to have any limitations. The author investigates, in a systematic theoretical approach, the reasons for these beautiful properties. He develops new models for power valves and transformers, thus enabling the designer to determine the properties of the amplifier during the design process. Mathematical models for the coupling of power valve(s) and output transformer are provided. These will generate new insights in a special kind of distortion: the dynamic damping factor distortion (DDFD). With mathematical models in the complex domain, especially the properties at the limits of our hearing range (from 20 Hz to 20 kHz) are investigated and the minimal stability criteria for the amplifier are formulated. The often-applied negative feedback in amplifiers is extensively modelled and discussed in relation to our hearing appreciating. And after all this theory a fine selection of special amplifiers is presented and discussed. You will notice in this book that the author not only writes about amplifier technique, but tells about the way the development of valve amplifiers can have an influence on your daily life; even the usefulness of patents is discussed. Summarizing: new theories and solutions for perfect audio with valve amplifiers. Not only the professional and the DIY-er but everyone who wants to understand valve amplifiers will read this book with much pleasure.

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More than 475 Audio Circuits from 30 Years of Elektor This USB Stick contains over 475 different audio circuits from the volumes 1995-2025 of Elektor. The article search feature allows you to search full-text content. The results are always displayed as pre-formatted PDF documents. Highlights Surround-sound decoder Compact amp Sampling rate converter Battery powered preamplifier Titan 2000 amplifier Crescendo Millennium amplifier Audio-DAC/ADC IR-S/PDFI receiver and transmitter High-End Power Amp Hi-fi Wireless Headset Paraphase Tone Control and more… On the Stick you will also find a folder with additional material such as PCB layouts, Gerber files and software. Specifications Storage 16 GB Interfaces 1x USB-A1x USB-C System requirements PC with Adobe Reader 7.0 or higher Web browser

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A Toolbox for Audio Lovers and Engineers Without any ambition to reach scientific levels, this book aims to be a toolbox for both audio lovers and high-end equipment designers. The elementary theory presented is the bare minimum for readers to grasp the operation and practical use of electrical, electromagnetic, physics, and electronic operations available in the designers’ toolbox. Each tool is explained in a minimum of words and theory without needless coverage of underlying equations or figures. The book chapters guide you through the process of designing quality amplifiers with vacuum tubes, from the very beginning, considering both technical and subjective requirements – in theory and practice. The book is a compilation of the author’s notes used in his professional and educational career but was nevertheless primarily written as a result of true love for the audiophile hobby.

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Valve Amplifiers are regarded by many to be the ne plus ultra when it comes to processing audio signals. The combination of classical technology and modern components has resulted in a revival of the valve amplifier. The use of toraidal-core output transformers, developed by the author over the past 15 years, has contributed to this revival. The most remarkable features of these transformers are their extremely wide frequency ranges and their very low levels of linear and nonlinear distortion. This book explains the whys and wherefores of toroidal output transformers at various technical levels, starting with elementary concepts and culminating in complete mathematical descriptions. In all of this, the interactions of the output valves, transformer and loudspeaker form the central theme. Next come the practical aspects. The schematic diagram of a valve amplifier often appears to be very simple at first glance, but anyone who has built a modern valve amplifier knows that a lot of critical details are hidden behind this apparent simplicity. These are discussed extensively, in connection with designs for amplifiers with output powers ranging from 10 to 100 watts. Finally, the author gives some attention to a number of special valve amplifiers, and to the theory and practice of negative feedback. In summary, this book offers innovative solutions for achieving perfect audio quality. Do-it-yourself builders, as well as persons who want to gain a deeper technical understanding of the complex world of audio transformers, valve amplifiers and audio signal processing, will find this book a rich and useful source of information.

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This book focuses more on practical aspects than on theory, and it has an contemplative nature, as though the author were viewing amplifiers from above. Knowledge elements are integrated and placed in the context of a broad overview. Even now tube amplifiers still sound great perhaps better than ever before. In part that is because we now have access to modern components such as toroidal output transformers, extremely high-quality resistors and capacitors, and many sorts of wire with good acoustic properties. Modern audio sources, such as CD players, and the latest top-end loudspeakers also enable us to appreciate how well tube amplifiers reproduce music even better than before. This new book from Menno van der Veen looks at tube amplifiers from more than just a theoretical perspective. It focuses primarily on the design phase, where decisions must be taken with regard to the purpose and requirements of the amplifier, and it addresses the following questions: How do these aspects relate to subjective and objective criteria? Which circuits sound the best, and why? If you want to develop and market an amplifier, what problems should you expect? What are the significance and meaning of measurements? Are they still meaningful, or have they lost their relevance? Thanks to the enormous processing power of computers, we can now measure more details than ever before. How can these new methods be applied to tube amplifiers? Previously it was sufficient to measure the frequency range, power and distortion of an amplifier in order to characterize the amplifier. Are these measurements still sufficient, or should we start measuring according to how we hear, using real music signals instead of waveforms from signal generators? The author sketches a future where amplifier measurements that conform to our sense of hearing enable us to arrive at new insights. This book focuses more on practical aspects than on theory, and it has an contemplative nature, as though the author were viewing amplifiers from above. Knowledge elements are integrated and placed in the context of a broad overview.

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