Amplifier History: The JBL SA-600
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
“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, […]
Audio Power Amplifier Design – Peter J Baxandall
In this 6 part series of articles published from January 1978 in the now defunct Wireless World magazine, Peter Baxandall takes the reader through some of the fundamentals of audio amplifier design as they were understood at the time. Baxandall_Audio Power Amplifier Design In 1978 there was still much discussion about feedback and how […]
The Theory of TIM – Matti Otala
Matti Otala follows up on earlier research on the subject of TIM. The Theory of TIM Matti Otala
Measuring TIM
This paper by Leinonen, Otala and Curl investigates the measurement of TIM, a hot topic in the 1970’s and early ’80’s after its potential to cause sonic degradation by the incorrect application of feedback around high loop gain solid state amplifiers. Now days (2017), there is a very complete and thoroughly in-depth understanding of TIM […]
A Concise Overview of TIM by Bob Cordell
This set of articles was written in the early 1980’s by Bob Cordell, a few years after Matti Otala (RIP) identified TIM (Transient Inter-Modulation) as the probable cause of sonic imperfections in high feedback solid state amplifiers in the 1970’s. Otala’s paper sent shock waves through the amplifier design community but sadly it ended up […]