MC Head Amp Circuit Compendium

Here is the new updated moving coil head amp designs compendium – updated 31 July 2019. The first file is a PDF compendium of about 28 different circuits with noise, distortion and current consumption details. All the LTspice sim files are zipped in the second file. What is immediately apparent from this is that having […]

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Richard Lee’s Ultra-Low Noise MC Head Amp

This design was a development of Marshall Leach’s MC head-amp from the 1970’s and to my knowledge, Richard Lee’s implementation presented here has not been bested in terms of noise – about 280pV/rt Hz in a well implemented exemplar. Importantly, it requires only about 12mA current in the +-15V rail powered version, and about a […]

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The Monolithic Op-Amp: A Tutorial Study

This was an invited paper at the ISSCC in 1974 by James Solomon, who at the time worked for National Semiconductor (acquired in 2011 by TI). Those were heady days in semiconductors, with major process and circuit design breakthroughs taking place at breakneck speed. The general purpose microprocessors’  pivotal role in powering the Apple II […]

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