336:). This impedance may vary in value with signal frequency and amplitude. This variable loading affects the amplifier's performance both because the amplifier has nonzero output impedance (it cannot keep its output voltage perfectly constant when the speaker load varies) and because the phase of the speaker load can change the stability margin of the amplifier. The influence of the speaker impedance is different between tube amplifiers and transistor amplifiers. The reason is that tube amplifiers normally use output transformers, and cannot use much negative feedback due to phase problems in transformer circuits. Notable exceptions are various "OTL" (output-transformerless) tube amplifiers, pioneered by Julius Futterman in the 1950s, or somewhat rarer tube amplifiers that replace the impedance matching transformer with additional (often, though not necessarily, transistorized) circuitry in order to eliminate parasitics and musically unrelated magnetic distortions. In addition to that, many solid-state amplifiers, designed specifically to amplify electric instruments such as guitars or bass guitars, employ current feedback circuitry. This circuitry increases the amplifier's output impedance, resulting in response similar to that of tube amplifiers.
550:
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is a considerable issue because design goals of such differ widely from design goals of likes of HiFi amplifiers. HiFi design largely concentrates on improving performance of objectively measurable variables. Instrument amplifier design largely concentrates on subjective issues, such as "pleasantness" of certain type of tone. Fine examples are cases of distortion or frequency response: HiFi design tries to minimize distortion and focuses on eliminating "offensive" harmonics. It also aims for ideally flat response. Musical instrument amplifier design deliberately introduces distortion and great non-linearities in frequency response. Former "offensiveness" of certain types of harmonics becomes a highly subjective topic, along with preferences towards certain types of frequency responses (whether flat or un-flat).
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series or of the composite wave-form that this series represents. It has been shown that weighting the harmonics by the square of the order correlates well with subjective listening tests. Weighting the distortion wave-form proportionally to the square of the frequency gives a measure of the reciprocal of the radius of curvature of the wave-form, and is therefore related to the sharpness of any corners on it. Based on said discovery, highly sophisticated methods of weighting of distortion harmonics have been developed. Since they concentrate in the origins of the distortion, they are mostly useful for the engineers who develop and design audio amplifiers, but on the other hand they may be difficult to use for the reviewers who only measure the output.
152:
206:(transistorized) amplification had become more common because of its smaller size, lighter weight, lower heat production, and improved reliability. Tube amplifiers have retained a loyal following amongst some audiophiles and musicians. Some tube designs command very high prices, and tube amplifiers have been going through a revival since Chinese and Russian markets have opened to global trade—tube production never went out of vogue in these countries. Many transistor-based
461:
solid-state -based circuitry. For example, solid-state circuitry such as operational transconductance amplifiers operated open loop, or MOSFET cascades of CMOS inverters, are frequently used in commercial applications to generate softer clipping than what is provided by generic triode gain stages. In fact, the generic triode gain stages can be observed to clip rather "hard" if their output is scrutinized with an oscilloscope.
542:. When the tube amplifier was operated at high volume, due to the high impedance of the rectifier tubes, the power supply voltage would dip as the amplifier drew more current (assuming class AB), reducing power output and causing signal modulation. The dipping effect is known as "sag." Sag may be desirable effect for some electric guitarists when compared with hard clipping. As the amplifier load or output increases this
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distributed loading are both in essence negative feedback methods, which enable less harmonic distortion along with other characteristics associated with negative feedback. Ultra-linear topology has mostly been associated with amplifier circuits based on research by D. Hafler and H. Keroes of Dynaco fame. Distributed loading (in general and in various forms) has been employed by the likes of McIntosh and Audio
Research.
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638:. Output power of as high as 15 watts can be achieved even with classic tubes such as the 2A3 or 18 watts from the type 45. Classic pentodes such as the EL34 and KT88 can output as much as 60 and 100 watts respectively. Special types such as the V1505 can be used in designs rated at up to 1100 watts. See "An Approach to Audio Frequency Amplifier Design", a collection of reference designs originally published by G.E.C.
36:
457:
Hamm. Monteith and
Flowers said: "In conclusion, the high voltage transistor preamplifier presented here supports the viewpoint of Mintz: 'In the field analysis, the characteristics of a typical system using transistors depends on the design, as is the case in tube circuits. A particular 'sound' may be incurred or avoided at the designer's pleasure no matter what active devices he uses.'"
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86:
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Large amounts of feedback, allowed by transformerless circuits with many active devices, leads to numerically lower distortion but with more high harmonics, and harder transition to clipping. As input increases, the feedback uses the extra gain to ensure that the output follows it accurately until the amplifier has no more gain to give and the output saturates.
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also affect greatly on softness (or lack of it) of clipping: long-tailed pair circuit, for example, has softer transition to clipping than a cathodyne. The coupling of the phase inverter and power tubes is also important, since certain types of coupling arrangements (e.g. transformer coupling) can drive power tubes to class AB2, while some other types can't.
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a problem-free load for music signal sources. By contrast, some transistor amplifiers for home use have lower input impedances, as low as 15 kΩ. Since it is possible to use high output impedance devices due to the high input impedance, other factors may need to be accounted for, such as cable capacitance and microphonics.
606:(THD) measurements of that epoch. It should be pointed out that this reference is somewhat ironic given its publication date of 1952. As such, it most certainly refers to "ear fatigue" distortion commonly found in existing tube-type designs; the world's first prototype transistorized hi-fi amplifier did not appear until 1955.
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But, as I was about to disassemble it and put the parts away, I wondered what the circuit would sound like without any feedback. That is, just a pentode with a transformer load. I figured it was going to be awful, so I was not prepared for what I heard, which was near sonic bliss. From note one, this
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Unlike their solid-state equivalents, tube rectifiers require time to warm up before they can supply B+/HT voltages. This delay can protect rectifier-supplied vacuum tubes from cathode damage due to application of B+/HT voltages before the tubes have reached their correct operating temperature by the
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In other words, soft clipping is not exclusive to vacuum tubes or even an inherent property of them. In practice the clipping characteristics are largely dictated by the entire circuitry and as so they can range from very soft to very hard, depending on circuitry. Same applies to both vacuum tube and
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acceleration of the diaphragm which causes sound pressure. Due to the principle of an electrodynamic speaker, most loudspeaker drivers ought to be driven by an electric current signal. The current signal drives the electrodynamic speaker more accurately, causing less distortion than a voltage signal.
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Loudspeakers usually load audio amplifiers. In audio history, nearly all loudspeakers have been electrodynamic loudspeakers. There exists also a minority of electrostatic loudspeakers and some other more exotic loudspeakers. Electrodynamic loudspeakers transform electric current to force and force to
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A single-ended amplifier will generally produce even as well as odd harmonics. A particularly famous research about "tube sound" compared a selection of single-ended tube microphone preamplifiers to a selection of push-pull transistorized microphone preamplifiers. The difference in harmonic patterns
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The tube sound is often subjectively described as having a "warmth" and "richness", but the source of this is by no means agreed on. Possible explanations mention non-linear clipping, or the higher levels of second-order harmonic distortion in single-ended designs, resulting from the tube interacting
456:
Hamm's paper was also countered by Dwight O. Monteith Jr and
Richard R. Flowers in their article "Transistors Sound Better Than Tubes", which presented transistor mic preamplifier design that actually reacted to transient overloading similarly as the limited selection of tube preamplifiers tested by
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Soft clipping is also not a product of lack of feedback alone: Tubes have different characteristic curves. Factors such as bias affect the load line and clipping characteristics. Fixed and cathode-biased amplifiers behave and clip differently under overdrive. The type of phase inverter circuitry can
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or more) in modern designs and as much as 1 MΩ in classic designs. The input impedance of the amplifier is a load for the source device. Even for some modern music reproduction devices the recommended load impedance is over 50 kΩ. This implies that the input of an average tube amplifier is
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A huge issue is that measurements of objective nature (for example, those indicating magnitude of scientifically quantifiable variables such as current, voltage, power, THD, dB, and so on) fail to address subjective preferences. Especially in case of designing or reviewing instrument amplifiers this
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in early transistor amplifiers. However, solid state amplifiers have been developed to be flawless and the sound is later regarded neutral compared to tube amplifiers. Thus the tube sound now means 'euphonic distortion.' The audible significance of tube amplification on audio signals is a subject of
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The most significant differences are, however, found in the output impedance. The output impedance of transistor amplifiers is typically less than 0.1 Ω, which denotes pure voltage feed for the speaker. In tube amplifiers, instead, the output impedance varies rather widely; from tenths of an ohm to
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Crossover distortion generates unpleasant high order harmonics with the potential to increase in percentage as signal level falls and is much more objectionable to the listener than distortion resulting from a smoothly curved characteristic, even if they have the same THD. Therefore it is desirable
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transistor amplifiers arrived on the consumer market. Earlier germanium-based designs with the much lower turn-on voltage of this technology and the non-linear response curves of the devices had not shown large amounts of cross-over distortion. Although crossover distortion is very fatiguing to the
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To demonstrate one aspect of this effect, one may use a light bulb in the feedback loop of an infinite gain multiple feedback (IGMF) circuit. The slow response of the light bulb's resistance (which varies according to temperature) can thus be used to moderate the sound and attain a tube-like "soft
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or distributed load operation with an appropriate output transformer. In practice, in addition to loading the plate terminal, distributed loading (of which ultra linear circuit is a specific form) distributes the load also to cathode and screen terminals of the tube. An Ultra-linear connection and
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In audio amplifiers, the bandwidth limitations introduced by compensation are still far beyond the audio frequency range, and the slew rate limitations can be configured such that full amplitude 20 kHz signal can be reproduced without the signal encountering slew rate distortion, which is not
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and bandwidth limitations imposed by dominant-pole compensation in transistor amplifiers. However, the effects of using low feedback principally apply only to circuits where significant phase shifts are an issue (e.g. power amplifiers). In preamplifier stages, high amounts of negative feedback can
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higher in the case of second-order harmonics, and one octave plus one fifth higher for third-order harmonics. The added harmonic tone is lower in amplitude, at about 1–5% or less in a no feedback amp at full power and rapidly decreasing at lower output levels. Hypothetically, a single-ended power
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did not exist, because practically all electronic amplification of audio signals was done with vacuum tubes and other comparable methods were not known or used. After introduction of solid state amplifiers, tube sound appeared as the logical complement of transistor sound, which had some negative
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However, phase shift is largely an issue only with global feedback loops. Design architectures with local feedback can be used to compensate the lack of global negative feedback magnitude. Design "selectivism" is again a trend to observe: designers of sound producing devices may find the lack of
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Large amounts of global negative feedback are not available in tube circuits, due to phase shift in the output transformer, and lack of sufficient gain without large numbers of tubes. With lower feedback, distortion is higher and predominantly of low order. The onset of clipping is also gradual.
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the output impedance approaches infinity. Practically all commercial audio amplifiers are voltage amplifiers. Their output impedances have been intentionally developed to approach zero. Due to the nature of vacuum tubes and audio transformers, the output impedance of an average tube amplifier is
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A psychoacoustic analysis tells us that high-order harmonics are more offensive than low. For this reason, distortion measurements should weight audible high-order harmonics more than low. The importance of high-order harmonics suggests that distortion should be regarded in terms of the complete
339:
The design of speaker crossover networks and other electro-mechanical properties may result in a speaker with a very uneven impedance curve, for a nominal 8 Ω speaker, being as low as 6 Ω at some places and as high as 30–50 Ω elsewhere in the curve. An amplifier with little or no
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then available. In power amplifiers most limitations come from the output transformer; low frequencies are limited by primary inductance and high frequencies by leakage inductance and capacitance. Another limitation is in the combination of high output impedance, decoupling capacitor and grid
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usually considerably higher than the modern audio amplifiers produced completely without vacuum tubes or audio transformers. Most tube amplifiers with their higher output impedance are less ideal voltage amplifiers than the solid state voltage amplifiers with their smaller output impedance.
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The distortion content of class-A circuits (SE or PP) typically monotonically reduces as the signal level is reduced, asymptotic to zero during quiet passages of music. For this reason class-A amplifiers are especially desired for classical and acoustic music since the distortion
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even more than five ohms (with 8 Ω loading). A source impedance of even a couple of ohms is able to weaken the speaker's EMF currents so that the effects are observable; and as the value exceeds 5 Ω, the speaker may function at some frequencies even halfly current-driven.
746:. For more complete simulations, engineers have been successful in developing transistor amplifiers that produce a sound quality very similar to the tube sound. Usually this involves using a circuit topology similar to that used in tube amplifiers.
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amplifier's second harmonic distortion might reduce similar harmonic distortion in a single driver loudspeaker, if their harmonic distortions were equal and amplifier was connected to the speaker so that the distortions would neutralize each other.
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amplifier, have a far more serious subjective effect than is indicated by any of the standard methods of measuring distortion –whether total harmonic distortion, conventional weighted distortion factor or the standard form of intermodulation
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Push–pull amplifiers use two nominally identical gain devices in tandem. One consequence of this is that all even-order harmonic products cancel, allowing only odd-order distortion. This is because a push–pull amplifier has a symmetric
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instead of silicon diodes, and some designs offer the choice of both rectifiers via a switch. Such an amplifier was introduced in 1989 by Mesa/Boogie, called "Dual
Rectifier", and the rectifier switching is the subject of a patent.
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added to the signal are of lower energy with soft clipping than hard clipping. However, soft clipping is not exclusive to tubes. It can be simulated in transistor circuits (below the point that real hard clipping would occur). (See
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The triode, despite being the oldest signal amplification device, also can (depending on the device in question) have a more linear no-feedback transfer characteristic than more advanced devices such as beam tetrodes and pentodes.
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The job of the amplifier is very simple. It must multiply the incoming signal voltage by a factor of about 20, and deliver a perfect replica of the signal to the speaker, independent of the impedance that the speaker presents to
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amplifier. In a class-A stage the average current drawn from the supply is constant with signal level, consequently it does not cause supply line sag until the clipping point is reached. Other audible effects due to using a tube
450:, wrote in 1973 that there is a major difference between the harmonic distortion components of a signal with greater than 10% distortion that had been amplified with three methods: tubes, transistors, or operational amplifiers.
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of these two topologies has henceforth been often incorrectly attributed as difference of tube and solid-state devices (or even the amplifier class). Push–pull tube amplifiers can be run in class A (rarely), AB, or B. Also, a
502:(NFB) as transistor amplifiers due to the large phase shifts caused by the output transformers and their lower stage gains. While the absence of NFB greatly increases harmonic distortion, it avoids instability, as well as
169:
364:, have quite different characteristics that are in some ways similar to the bipolar transistor. Yet MOSFET amplifier circuits typically do not reproduce tube sound any more than typical bipolar designs. The reason is
722:. However, class-D topology (which is vastly more efficient than class B) is more and more frequently applied where traditional design would use class AB because of its advantages in both weight and efficiency.
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300 power amp. In
America, Moscode and Studio Electric use this method, but use MOSFET transistors for power, rather than bipolar. Pathos, an Italian company, has developed an entire line of hybrid amplifiers.
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Modern premium components make it easy to produce amplifiers that are essentially flat over the audio band, with less than 3 dB attenuation at 6 Hz and 70 kHz, well outside the audible range.
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characteristics of tubes over transistors for electric guitar, bass, and other instrument amplifiers. In this case, generating deliberate (and in the case of electric guitars often considerable) audible
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On the other hand, the dominant pole compensation in transistor amplifiers is precisely controlled: exactly as much of it can be applied as needed to strike a good compromise for the given application.
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30%). Under this condition there is a major difference in the harmonic distortion components of the amplified signal, with tubes, transistors, and operational amplifiers separating into distinct groups
760:, it is possible to have tube amplifiers with the characteristic wide bandwidth of modern transistor amplifiers, including using push–pull circuits, class AB, and feedback. Some enthusiasts, such as
161:
892:
It was crossover distortion that was the root of the so-called ʻtransistor soundʼ imputed to early solid-state high fidelity equipment. Bias arrangements are used to overcome crossover distortion.
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Demonstration of the dynamics on electric guitar with a tube overdrive set to a crunch sound. Barely touching the strings produces an almost clean sound; harder playing results in distortion.
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442:
In the recording industry and especially with microphone amplifiers it has been shown that amplifiers are often overloaded by signal transients. Russell O. Hamm, an engineer working for
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Early tube amplifiers had power supplies based on rectifier tubes. These supplies were unregulated, a practice which continues to this day in transistor amplifier designs. The typical
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distortion is a unique pattern of simple and monotonically decaying series of harmonics, dominated by modest levels of second harmonic. The result is like adding the same tone one
565:
With added resistance in series with the high-voltage supply, silicon rectifiers can emulate the voltage sag of a tube rectifier. The resistance can be switched in when required.
681:. SET amps have a power consumption of a minimum of 8 times the stated stereo power. For example, a 10 W stereo SET uses a minimum of 80 W, and typically 100 W.
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Mastering engineer R. Steven Mintz wrote a rebuttal to Hamm's paper, saying that the circuit design was of paramount importance, more than tubes vs. solid state components.
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depends on the sensitivity of the loudspeaker and the size and acoustics of the room as well as amplifier power output. Their low power also makes them ideal for use as
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The effect of dominant pole compensation is that gain is reduced at higher frequencies. There is increasingly less NFB at high frequencies due to the reduced loop gain.
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Audio amplifiers, with a few very special exceptions, approximate to perfect voltage sources; i.e., they aspire to a zero output impedance across the audio band.
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The smooth transfer curves of Class A amplifiers have a characteristic which is monotonic, that is to say the distortion goes down as the output declines.
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feedback and resulting higher distortion beneficial, designers of sound reproducing devices with low distortion have often employed local feedback loops.
990:
Branch, John D. (2007-05-23). "Postmodern
Consumption and the High-Fidelity Audio Microculture". In Russell Belk; Russell Belk Jr.; John Sherry (eds.).
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decreases as the music gets quieter. Class-A amplifiers measure best at low power. Class-AB and B amplifiers measure best just below max rated power.
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Class-AB push–pull topology is nearly universally used in tube amps for electric guitar applications that produce power of more than about 10 watts.
482:. If interconnections are made from long cables (for example guitar to amp input), a high source impedance with high cable capacitance will act as a
54:
920:
Unusually, there is something of a consensus that audible crossover distortion was responsible for the so-called ʻtransistor soundʼ of the 1960s.
1381:
Mills, Paul G. L.; Hawksford, M. O. J. (March 1989). "Distortion
Reduction in Moving-Coil Loudspeaker Systems Using Current-Drive Technology".
764:, have built amplifiers using transistors and MOSFETs that operate in class A, including single ended, and these often have the "tube sound."
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cores, so this topology is often seen by HIFI-audio enthusiasts and do-it-yourself builders as the ultimate engineering approach to the tube
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Tube amplifiers sound better because of the euphonic distortions they add to the music, as well as plenty of other reasons I'll cover below.
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It effectively bridges the gap between solid-state and tube sound, blending tube and transistor virtues into a musically satisfying whole.
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More recently, a researcher has introduced the asymmetric cycle harmonic injection (ACHI) method to emulate tube sound with transistors.
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topology (with more or less pure low-level class-A capability depending on the standing bias current used), in order to deliver greater
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1319:
R. S. Babbs; D. H. W. Busby; P. S. Dallosso; C. Hardcastle; J. C. Latham; W. A. Ferguson (1959). "Three-valve
Stereophonic Amplifier".
781:
549:
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One interference which may reasonably be drawn is that any sharp kinks in the linearity curve, as usually occur in any class-AB
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negative feedback will always perform poorly when faced with a speaker where little attention was paid to the impedance curve.
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SET amplifiers show poor measurements for distortion with a resistive load, have low output power, are inefficient, have poor
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1001:
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is usually the goal. The term can also be used to describe the sound created by specially-designed transistor amplifiers or
673:(W) for a 2A3 tube amp to 8 W for a 300B up to the practical maximum of 40 W for an 805 tube amp. The resulting
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Blackheart 5W single-ended class-A guitar amplifier chassis with an additional GZ34 valve rectifier modification installed
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277:) produce a monotonically decaying harmonic distortion spectrum. Even-order harmonics and odd-order harmonics are both
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Tubes are added to solid-state amplifiers to impart characteristics that many people find audibly pleasant, such as
72:
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easily be employed. Such designs are commonly found from many tube-based applications aiming to higher fidelity.
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will increase distortion of the output signal. Sometimes this sag effect is desirable for guitar amplification.
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in the 1950s, electronic amplifiers used vacuum tubes (known in the United
Kingdom as "valves"). By the 1960s,
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Sony
Corporation 1999. Sony compact disc player CDP-XB930 Operating Instructions. (1). Specifications, p.20.
470:
1780:"Using Transistors to Emulate Vacuum Tube Sound Quality Based on Asymmetric Cycle Harmonic Injection Method"
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limiting" of the output, though other aspects of the "tube sound" would not be duplicated in this exercise.
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may have crossover distortion that will be typically high order and thus sonically very undesirable indeed.
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All amplifiers, regardless of class, components, or topology, have some measure of distortion. This mainly
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ear and perceptible in listening tests, it is also almost invisible (until looked for) in the traditional
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and high measured harmonic distortion. But they perform somewhat better in dynamic and impulse response.
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1854:- Massive collection (many gigabytes) of scanned original tube data sheets and technical information.
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1490:. Jipihorn. Without giving the standard weakest link answer, how important is the amp as a component?
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832:
822:
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This paper, however, points out that amplifiers are often severely overloaded by signal transients (
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1782:, 2019 IEEE 8th Global Conference on Consumer Electronics (GCCE), Osaka, Japan, 2019, pp. 752-753.
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1073:
Shorter, D. E. L. (April 1950). "The Influence of High-Order Products in Non-Linear Distortion".
1025:
837:
474:
298:
1738:"Why single-ended tube amplifiers? About distortion behavior between SE amplifiers and speakers"
1715:"Why single-ended tube amplifiers? About distortion behavior between SE amplifiers and speakers"
1686:"First-Hand:The World's First Transistor Hi-Fi System - Engineering and Technology History Wiki"
539:
933:
294:
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was something special. Turns out, I had built a transconductance amp more or less by accident.
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Tubes vs Transformers: An esoteric exploration of tubes, transformers, tone and transcendence
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597:. This crossover distortion was found especially annoying after the first silicon-transistor
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or preamplifiers. Tube amplifiers are also preferred by some listeners for stereo systems.
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1246:(D.Tech. thesis). Graz, Austria: Graz University of Technology. p. 27. Archived from
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have certain similarities in their transfer characteristics. Later forms of the tube, the
8:
231:
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Branch, John (2007). "Postmodern Consumption and the High-Fidelity Audio Microculture".
718:, typically 12–25 watts and higher. Contemporary designs normally include at least some
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modeling devices that try to closely emulate the characteristics of the tube sound.
50:
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969:
773:
479:
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U.S. Patent 5168438: Selectable dual rectifier power supply for musical amplifier
1389:(3). University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK: 129–148.
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That high-order harmonics are more offensive than low has long been recognised...
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134:
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1323:(2nd ed.). Peterborough, New Hampshire: Audio Amateur Press. p. 123.
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1430:"The Caged Frog -- A Pentode Based Transconductance Amplifier for Headphones"
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The special feature among tetrodes and pentodes is the possibility to obtain
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There has been considerable debate over the characteristics of tubes versus
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1371:
Rotel stereo integrated amplifier RA-935BX owners manual. MN10002975-A. p.4
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A First Course in Electronics, pg 414-416. Anwar A. Khan and Kanchan K. Dey
1131:
814:
690:
543:
244:
1839:
1538:"Comments on 'Tubes Versus Transistors – Is There an Audible Difference?'"
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A characteristic feature of most tube amplifier designs is the high input
301:. Power amplifiers are of the push-pull type to avoid the inefficiency of
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635:
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Langford-Smith, F. Radiotron Designer's Handbook 4th Edition. 1952, p. 3
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on overdrive, are straightforward to produce in a transistor circuit or
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Running with the Devil: power, gender, and madness in heavy metal music
447:
329:
252:
199:
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141:, and keyboard players in several genres also prefer the sound of tube
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Meriläinen, Esa (February 2010). "5.7 The Secret of Tube Amplifiers".
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Soft clipping is a very important aspect of tube sound especially for
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558:
531:
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214:(metal–oxide–semiconductor field-effect transistor) devices in their
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International Conference on Acoustics, Speech, and Signal Processing
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1130:. Peterborough, New Hampshire: Audio Amateur: 7–11. Archived from
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Consumer Culture Theory, Volume 11 (Research in Consumer Behavior)
780:(tiny triode tubes) to control large bipolar transistors in their
1105:
792:
756:, and modern sources, whether digital or analogue, and wide band
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amplifier produces low distortion for any given level of applied
361:
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1662:(4th ed.). Sydney, Australia: Wireless Press. p. 610.
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amplifier should not normally ever be driven into clipping. The
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Some individual characteristics of the tube sound, such as the
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A Novel Power Acmplifier Topology Without Crossover Distortion
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Typical (non-OTL) tube power amplifiers could not use as much
527:
162:
Playing dynamics with an electric guitar and a tube overdrive
105:
859:
Universal system and output transformer for valve amplifiers
27:
Characteristic quality of sounds from vacuum tube amplifiers
1794:"The Volksamp Aleph 30 SE Power Amplifier (product review)"
1515:"Tubes Versus Transistors –Is There an Audible Difference?"
1207:"Tubes Versus Transistors –Is There an Audible Difference?"
670:
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between a typical tube design and a typical MOSFET design.
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Some instrument tube amplifier designs use a vacuum tube
381:
1829:"Tubes vs. Transistors: Is There An Audible Difference?"
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473:, in part due to the characteristics of the inexpensive
85:
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Tubes versus transistors in electric guitar amplifiers
904:
Self, Douglas (2013). "10. Output Stage Distortions".
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even necessary for reproducing actual audio material.
324:
Loudspeakers present a reactive load to an amplifier (
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to reduce crossover distortion to a minimum amount.
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225:
45:
may be too technical for most readers to understand
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1555:
268:
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1060:pages 43-44 discusses the "tube sound" sought by
876:Carr, Joseph J. (1996) . "6-7 Power Amplifiers".
469:Early tube amplifiers often had limited response
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1108:. New York, New York: Audio Engineering Society.
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1157:Ask the Doctors: Tube vs. Solid-State Harmonics
1150:
1095:Geddes, Earl R.; Lee, Lidia W. (October 2003).
568:Electric guitar amplifiers often use a class-AB
1380:
1017:
878:Linear IC Applications: A Designer's Handbook
855:
1831:. Presented at the 43rd convention of the
1698:Pete Millett's DIY Audio pages. Tube data.
1361:. Japan: Sony Corporation. 1999. p. 1.
1200:
1198:
1098:Auditory Perception of Nonlinear Distortion
706:amplifier designs have until recently used
685:Single-ended pentode and tetrode amplifiers
424:
130:continuing debate among audio enthusiasts.
1399:
1321:Mullard Tube Circuits for Audio Amplifiers
1234:
908:(6th ed.). Focal Press. p. 270.
1564:"Transistors Can Sound Better Than Tubes"
1455:Self, Douglas (2002) . "Damping factor".
1018:Fliegler, Ritchie; Eiche, Jon F. (1993).
996:(1 ed.). JAI Press. pp. 79–99.
865:. 118th AES Convention, Barcelona, Spain.
728:
73:Learn how and when to remove this message
57:, without removing the technical details.
1542:Journal of the Audio Engineering Society
1485:"The Amplifier Guru speaks: Bob Cordell"
1383:Journal of the Audio Engineering Society
1211:Journal of the Audio Engineering Society
1195:
931:
791:
577:with this amplifier class are unlikely.
548:
112:(valve amplifier in British English), a
84:
1827:Hamm, Russell O. (September 14, 1972).
1735:
1712:
1483:Smith, Peter Jay; Cordell, Bob (2005).
1174:
669:SETs usually only produce about 2
609:
14:
1860:
1625:: CS1 maint: archived copy as title (
989:
959:
953:
198:Before the commercial introduction of
1535:
1457:Audio Power Amplifier Design Handbook
1021:Amps! The Other Half of Rock 'n' Roll
734:Tube sound from transistor amplifiers
399:current or transconductance amplifier
55:make it understandable to non-experts
1561:
1459:(3rd ed.). Newnes. p. 25.
1274:
1204:
849:
767:
642:Single-ended triode (SET) amplifiers
493:
343:
93:section of a modern guitar amplifier
29:
1237:"4 Crossover Distortion in Class B"
1235:Meusburger, Walter (October 1999).
1181:W. Bussey & R. Haigler (1981).
388:
24:
1052:, Wesleyan University Press, 1993
702:The majority of modern commercial
371:
281:multiples of the input frequency.
150:
25:
1894:
1536:Mintz, R. Steven (October 1973).
1404:. Createspace. pp. 111–112.
521:
1512:
1280:"Audio, Distortion and Feedback"
1119:Howard, Keith (September 2005).
807:
405:
226:Musical instrument amplification
184:Problems playing this file? See
166:
89:Vacuum tubes glowing inside the
34:
1785:
1772:
1753:
1729:
1706:
1692:
1678:
1642:
1633:
1588:
1577:
1529:
1506:
1476:
1448:
1422:
1402:Current-Driving of Loudspeakers
1393:
1374:
1365:
1355:CDP-XB930/XB930E service manual
1346:
1337:
1312:
1301:
1286:. Harmonic Distortion and Sound
1268:
1228:
1191:. pp. Volume 6 p. 800–803.
1169:Volume cranked up in amp debate
1141:
1112:
269:Harmonic content and distortion
1840:Scientists vs Audiophiles 1999
1648:
1088:
1066:
1042:
1011:
925:
897:
869:
634:amplifier for use with normal
534:, perhaps half-wave, a choke (
13:
1:
1810:
1659:Radiotron Designer's Handbook
1205:Hamm, Russell O. (May 1973).
1171:—Electronic Engineering Times
974:10.1016/S0885-2111(06)11004-2
962:Research in Consumer Behavior
1651:"14 Fidelity and distortion"
1573:. Audio Engineering Society.
1482:
1081:(266). London, UK: 152–153.
1072:
932:Rockwell, Ken (2021-02-28).
906:Audio Power Amplifier Design
903:
464:
350:bipolar junction transistors
7:
1649:Langford-Smith, F. (1952).
1118:
1094:
1048:For example, Robert Walser
800:
697:
255:of the output transformer.
120:. At first, the concept of
10:
1899:
1792:Olsher, Dick (July 2001).
1791:
584:
478:resistor, which acts as a
257:
230:Some musicians prefer the
193:
1833:Audio Engineering Society
1736:de Lima, Eduardo (2005).
1713:de Lima, Eduardo (2005).
1454:
875:
856:van der Veen, M. (2005).
833:British Valve Association
823:Audio system measurements
604:Total harmonic distortion
222:curve is more tube-like.
1432:. ecp.cc. 22 August 2010
1159:—Universal Audio Webzine
1128:Multi Media Manufacturer
934:"Why Tubes Sound Better"
843:
581:tube's built-in heater.
425:"Intentional distortion"
218:sections, because their
104:) is the characteristic
1818:The Cool Sound of Tubes
1026:Hal Leonard Corporation
880:. Newnes. p. 201.
838:Virtual Valve Amplifier
796:Directly heated triodes
622:, and also cancels the
299:transfer characteristic
1075:Electronic Engineering
797:
729:Intentional distortion
554:
208:audio power amplifiers
155:
94:
1701:RCA 2A3 Power Triode.
795:
552:
154:
143:instrument amplifiers
110:vacuum tube amplifier
88:
1822:IEEE Spectrum Online
1562:Monteith, Dwight O.
1517:. Milbert Amplifiers
1106:AES 115th Convention
675:sound pressure level
610:Push–pull amplifiers
599:class-B and class-AB
595:crossover distortion
380:(typically 100
127:crossover distortion
125:connotations due to
1798:Enjoy the Music.com
589:The benefit of all
366:circuit differences
1778:Li, Jerry (2019),
1765:2008-03-18 at the
1688:. 12 January 2015.
828:Boutique amplifier
798:
754:passive components
593:is the absence of
591:class-A amplifiers
555:
475:passive components
448:Sear Sound Studios
319:relative to signal
303:Class A amplifiers
260:Distortion (music)
156:
108:associated with a
95:
1883:Audio engineering
1852:Tube Data Archive
1800:. 5th paragraph.
1760:System distortion
1513:Hamm, Russell O.
1411:978-1-4505-4400-9
1003:978-0-7623-1446-1
983:978-0-7623-1446-1
915:978-0-240-52613-3
768:Hybrid amplifiers
720:negative feedback
500:negative feedback
494:Negative feedback
412:guitar amplifiers
344:Design comparison
311:class-B amplifier
171:
83:
82:
75:
16:(Redirected from
1890:
1878:Audio amplifiers
1868:Valve amplifiers
1838:Reisch, George.
1805:
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1757:
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1721:. Archived from
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811:
810:
774:Musical Fidelity
540:filter capacitor
480:high-pass filter
389:Output impedance
173:
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153:
78:
71:
67:
64:
58:
38:
37:
30:
21:
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1887:
1858:
1857:
1816:Barbour, Eric.
1813:
1808:
1790:
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1777:
1773:
1767:Wayback Machine
1758:
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1598:
1596:"Archived copy"
1594:
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1571:J Audio Eng Soc
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1101:
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1071:
1067:
1062:Eddie Van Halen
1047:
1043:
1036:
1016:
1012:
1004:
988:(also found in
984:
958:
954:
942:
940:
938:KenRockwell.com
930:
926:
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770:
736:
731:
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687:
648:damping factors
644:
612:
587:
571:
524:
496:
484:low-pass filter
467:
408:
391:
374:
372:Input impedance
346:
271:
266:
228:
196:
191:
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182:
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179:
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167:
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157:
151:
135:electric guitar
118:audio amplifier
79:
68:
62:
59:
51:help improve it
48:
39:
35:
28:
23:
22:
15:
12:
11:
5:
1896:
1886:
1885:
1880:
1875:
1870:
1856:
1855:
1849:
1848:, March, 1999.
1836:
1825:
1812:
1809:
1807:
1806:
1784:
1771:
1769:, Gerrit Boers
1752:
1728:
1725:on 2007-08-15.
1705:
1691:
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1410:
1392:
1373:
1364:
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1336:
1329:
1311:
1300:
1267:
1227:
1217:(4): 267–273.
1194:
1173:
1161:
1149:
1140:
1137:on 2005-12-21.
1121:"Weighting up"
1111:
1087:
1065:
1041:
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1002:
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819:
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769:
766:
744:digital filter
735:
732:
730:
727:
699:
696:
686:
683:
643:
640:
611:
608:
586:
583:
569:
523:
522:Power supplies
520:
495:
492:
466:
463:
407:
404:
390:
387:
373:
370:
352:. Triodes and
345:
342:
279:natural number
270:
267:
264:Guitar effects
227:
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1674:
1661:
1660:
1652:
1645:
1636:
1628:
1622:
1608:on 2013-11-08
1604:
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1330:1-882580-03-6
1326:
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1285:
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1277:
1271:
1264:
1253:on 2007-11-20
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1058:0-8195-6260-2
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1035:9780793524112
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1005:
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887:0-7506-3370-0
883:
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755:
752:Using modern
750:
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406:Soft clipping
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273:Triodes (and
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139:electric bass
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43:This article
41:
32:
31:
19:
1873:Vacuum tubes
1843:
1821:
1801:
1797:
1787:
1774:
1755:
1744:. Retrieved
1731:
1723:the original
1718:
1708:
1700:
1694:
1680:
1663:
1658:
1644:
1635:
1610:. Retrieved
1603:the original
1590:
1579:
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1541:
1531:
1519:. Retrieved
1508:
1499:
1492:. Retrieved
1478:
1470:
1466:0-7506-56360
1456:
1450:
1441:
1434:. Retrieved
1424:
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1376:
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1295:
1288:. Retrieved
1283:
1276:Pass, Nelson
1270:
1261:
1255:. Retrieved
1248:the original
1243:
1230:
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937:
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871:
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815:Music portal
787:
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758:loudspeakers
751:
748:
737:
724:
701:
691:ultra-linear
688:
668:
656:
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544:voltage drop
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397:In an ideal
396:
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365:
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295:odd symmetry
291:
287:
283:
272:
249:
240:
229:
197:
183:
132:
121:
101:
97:
96:
69:
63:October 2017
60:
44:
1845:Stereophile
1835:, New York.
762:Nelson Pass
740:waveshaping
628:transformer
444:Walter Sear
326:capacitance
204:solid state
200:transistors
114:vacuum tube
102:valve sound
18:Valve sound
1862:Categories
1811:References
1746:2016-03-15
1612:2014-01-11
1494:11 October
1436:14 October
1290:12 October
1257:2011-03-18
943:2022-01-05
776:'s use of
716:efficiency
614:A class-A
427:section.)
334:resistance
330:inductance
258:See also:
253:inductance
237:distortion
232:distortion
220:distortion
186:media help
122:tube sound
98:Tube sound
1548:(8): 651.
968:: 79–99.
778:Nuvistors
616:push–pull
575:rectifier
559:rectifier
532:rectifier
504:slew rate
471:bandwidth
465:Bandwidth
420:harmonics
378:impedance
251:with the
241:overdrive
1763:Archived
1719:Audiopax
1673:testing.
1621:cite web
1278:(2008).
801:See also
708:class-AB
698:Class AB
659:harmonic
636:speakers
620:feedback
538:) and a
536:inductor
1521:19 July
1284:PassDiy
1187:. IEEE
782:NuVista
679:preamps
626:in the
585:Class A
362:pentode
358:tetrode
354:MOSFETs
275:MOSFETs
245:digital
194:History
116:-based
49:Please
1463:
1408:
1327:
1056:
1032:
1000:
980:
912:
884:
663:octave
212:MOSFET
91:preamp
1741:(PDF)
1668:or AB
1654:(PDF)
1606:(PDF)
1599:(PDF)
1567:(PDF)
1488:(PDF)
1359:(PDF)
1251:(PDF)
1240:(PDF)
1135:(PDF)
1124:(PDF)
1102:(PDF)
863:(PDF)
844:Notes
712:power
704:Hi-fi
632:Hi-fi
528:anode
416:hi-fi
216:power
133:Many
106:sound
1627:link
1523:2009
1496:2013
1461:ISBN
1438:2012
1406:ISBN
1325:ISBN
1292:2013
1054:ISBN
1030:ISBN
998:ISBN
978:ISBN
910:ISBN
882:ISBN
714:and
671:watt
624:flux
414:. A
360:and
332:and
262:and
210:use
100:(or
1842:in
1820:in
1501:it.
1221:THD
970:doi
446:at
239:or
53:to
1864::
1796:.
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