Tube Amps Origins and History
What is a tube amp? A tube amp is the type of amplifier which operates on vacuum tube or valves. In audio applications, tubes are still greatly desired by stereo enthusiasts and professional users. A tube amplifier is ideal for home listening because it produces a more natural and warmer valve sound.
The origins and history The transistor was invented in 1947 but previously, every practical amplifier was made from thermionic tubes. The initial utilization of tube amplification was when long-distant telephone signals were being generated. Later, the valve application penetrated to the wireless market in early 30's. In due course, tube amp for music (and later television) was built.
Before world war 1, almost every tube amplifier was of low gain while linearity entirely depended on the valve's inherent linearity. At full power, this was about 5% distortion. In 1927, negative feedback was invented. With this technique, amplifiers can trade again especially for reduced distortion levels and reduced output impedance.
Williamson amplifier was introduced in 1947. It was well advanced in many respects such as successful use of negative feedback. To the audio power amplifier design, this amplifier was a turning point.
After world war 2, there was dramatic technical progress and also industrial scale production economies. After the war, there was increased affluence which brought an expanding and substantial consumer market. A more advanced tube amp whose design could be marketed at an affordable price also came. As a result, in 1960's electronic gramophone players increased and this also marked the beginning of high fidelity that could drive loudspeakers of full frequency range to extreme volume levels. This also came with spreading of TV and this produced a golden age to tube development and in development of design of the tube amplifier circuits.
Valve tubes produce an "even harmonic distortion" has a more pleasant sound to ears compared to transistors. However, some people and musicians prefer solid state amplification because of its high reliability and low cost, not the tone'
A tube amplifier responds differently from a transistor amplifier when the signal levels approach or reach point of clipping. For tube amplifiers, transition is less abrupt compared to solid state unit. Hence at an onset of clipping, the form of distortion has less grating.
"In audio applications, valves & tubes continue to be highly desired by most professional users and stereo enthusiasts, they advocate the use of tube amplifiers for home listening and say that tube amplifiers produce a warmer and more natural valve sound." - Wikipedia
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