Input audio preamplifier used for laboratory measurements

This article looks at pre-input low-frequency amplifiers for laboratory work. The task was to study, design and build a fully functional pre-input amplifier for use in low frequency audio technology. In each section, we will discuss the various preamps, which are classified according to signal processing parameters. The construction of each amplifier uses discrete components and operational amplifiers. The second part of the article looks at different measuring devices, such as input sensitivity, transfer characteristics and input impedance etc., which would form part of the amplifier