How to wire-up a Dual Mono Bloc Amplifier
in Power amplifiers, Technical
A few people have asked about wiring up a dual mono amp aka dual mono bloc. In a dual mono bloc there are separate power supplies and lots of opportunity for cross channel ground loops and ordinary ‘classic’ ground loops as well. This wiring scheme addresses the situation were unbalanced connections between the source equipment […]
Noise in Electronic Circuits
in Technical
I’ve gathered a few articles here on noise as a go-to reference for anyone interested in the subject. These articles really focus on Johnson noise and not induced noise which is discussed in depth in the ‘Ground Loops’ post elsewhere on this site. I will update this post with new material as and when it […]
Amplifier History: The JBL SA-600
in Technical
The beautifully styled JBL SA-600 amplifier was launched by the James B. Lansing company in 1966, and Bart Locanthi (the designer) wrote the technical article linked to at the bottom of this write-up in January 1967. I’ve included this in the hifisonix power amplifier library because it is one of the earliest – if not […]
Solid State Feedback Amplifiers: A Short History
in Technical
“Why, sometimes I’ve believed as many as six impossible things before breakfast.” ― Lewis Carroll, Alice in Wonderland A Future Without Feedback by Martin Colloms There is no mysticism in amplifier design, just serious science. —Andrey A. Danilov Introduction You will recall from the The Theory of TIM by Matti Otala elsewhere on this site, […]
Technical Requirements of Phono Preamplifiers by Tomlinson Holman
in Technical, Vinyl preamps
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 which it could be argued was triggered by the arrival of very high performance turntables […]
Richard Lee’s Ultra-Low Noise MC Head Amp
in Technical, Vinyl preamps
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 […]