Technical Requirements of Phono Preamplifiers by Tomlinson Holman
The two articles below were written in the 1970’s, nearly a decade before the arrival of the CD and the ‘perfect sound forever’ claim made by Philips. There was a lot of focus on phono amplifier performance at the time…
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,…
Class A Buffering the Correct Way
Here’s a simple way to force an opamp output stage to run in class A when used with a discrete buffer output stage – it takes just 1 resistor to provide a near constant current source load. Operating the opamp…
The ‘Feedback is Bad’ Fallacy
This is one of the most depressing articles I’ve read in a long time about ‘feedback being bad’; it is filled with inaccuracies and for most part plain wrong at every level. Aimed at people who are not technically literate…
CFA vs. VFA: A Short Primer For the Uninitiated
This article was written in 2014 in response to what can only be described as a vitriolic debate as to what constituted a CFA on diyAudio.com. At the time, many of the participants were struggling to grasp the fundamental differences…
