source - 14 to 70 mv dc
gain - 50
gain - 50
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There is a Nyquist noise that cannot be eliminated. It can be lessened by using small impedances or by using low temperatures, or combinations of both.
Other noise may be caused by power supplies or poor components or poor design and these can be fixed.
Other noise may be caused by power supplies or poor components or poor design and these can be fixed.
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An electronic circuit for amplification of signals within or somewhat beyond the audio frequency range (generally regarded as 20 to 20,000 Hz). Audio amplifiers may function as voltage amplifiers (sometimes called preamplifiers), power amplifiers, or both. In the last case, they are often called integrated amplifiers. See also Power amplifier.
The function of integrated amplifiers (or of the combination of separate voltage amplifiers and power amplifiers used together) is to amplify a weak signal, such as from a microphone, phonograph pickup, tape player, radio tuner, or compact disc player, to a level capable of driving a loudspeaker or other type of transducer such as headphones at the desired sound level. Power amplifiers may have power ratings ranging from less than 1 W to several hundreds of watts. Stereo amplifiers consist of two identical, but electrically independent, amplifier circuits housed in a single chassis, often sharing a common power supply. Audio amplifiers are commonly constructed with solid-state devices (transistors and integrated circuits), although some amplifiers using vacuum tubes as the active, amplifying devices are still manufactured. See also Amplifier; Integrated circuits; Loudspeaker; Transistor; Vacuum tube.
The ideal amplifier delivers an output signal that, aside from its higher power level, is identical in relative spectral content to the input signal. Normally, various forms of distortion are generated by the amplifier, such as harmonic distortion (multiples of the desired signal frequency), intermodulation distortion (spurious sum or difference frequencies created when multiple tones are applied to the amplifier simultaneously, as in the case of music or speech amplification), and transient intermodulation distortion (caused by rapid fluctuations of the input signal level). All forms of distortion are measured as percentages of the desired signal amplitude. Generally, distortion levels of under 1% or 0.5% are considered to be low enough for high-fidelity applications.
The function of integrated amplifiers (or of the combination of separate voltage amplifiers and power amplifiers used together) is to amplify a weak signal, such as from a microphone, phonograph pickup, tape player, radio tuner, or compact disc player, to a level capable of driving a loudspeaker or other type of transducer such as headphones at the desired sound level. Power amplifiers may have power ratings ranging from less than 1 W to several hundreds of watts. Stereo amplifiers consist of two identical, but electrically independent, amplifier circuits housed in a single chassis, often sharing a common power supply. Audio amplifiers are commonly constructed with solid-state devices (transistors and integrated circuits), although some amplifiers using vacuum tubes as the active, amplifying devices are still manufactured. See also Amplifier; Integrated circuits; Loudspeaker; Transistor; Vacuum tube.
The ideal amplifier delivers an output signal that, aside from its higher power level, is identical in relative spectral content to the input signal. Normally, various forms of distortion are generated by the amplifier, such as harmonic distortion (multiples of the desired signal frequency), intermodulation distortion (spurious sum or difference frequencies created when multiple tones are applied to the amplifier simultaneously, as in the case of music or speech amplification), and transient intermodulation distortion (caused by rapid fluctuations of the input signal level). All forms of distortion are measured as percentages of the desired signal amplitude. Generally, distortion levels of under 1% or 0.5% are considered to be low enough for high-fidelity applications.