In audio design, we all "stand on the shoulders of giants". Some of them I had the privilege to interview. But there are many, many people who do interesting things in audio and document their adventures on their websites. And oh yes, the * indicates they have written for Linear Audio. It's probably impossible to list them all here, but I will add whatever I find, in no particular order. Should you know of a place you think should be listed here, just let me know!
You need to read Mike Renardson! Most people would have heard from him, if so, as the designer of audio (power) amplifiers. But he also has published short articles and posts with deep technical insight, and if you are technically interested (which you are if you are here), check him out.
For starters, read about the effects of feedback on harmonics in an amplifier. Even the list of references at the ends is a treasure trove. Recommended!
Much of my listening acuity (such as it is...) I got by talking and listening with Hans Beekhuyzen. Hans is a long-time audio writer and listener who has recently begun to publish educational YouTube videos about audio, perception and technical subjects. His The HansBeekhuyzen Channel is a treasure trove of of audio experience and knowledge. Highly recommended.
Just recently discovered (thanks Mason Green!) what is probably the worlds largest (and I don't say that lightly) store of scanned magazines related to engineering, audio radio, broadcastng, what have you! A subset of this contains links to ALL, with very few exceptions, Wreless World and it's pre- and post-decessor issues. A veritable gold mine.
For those of you who are interested in tube equipment and the recent history thereof, Vacuum Tube Valley magazine is a rich source. Thanks to Robert Schuelke for bringing this to my attention.
Another large source of articles from Wireless World, not only audio but basically the whole contents of historical journal. Compiled by Keith Snook.
Combine the above link with Douglas Self's collection who documents not only his own audio adventures but also many articles and developments by others; a very extensive audio tech history repository: http://www.douglas-self.com/
John Broskie's place for anything tube.
Stuart Yaniger*'s place, who's interests are very much my own. And he writes a mean book review for Linear Audio.
Bob Cordell*, who earned his stripes in both amplifier design as well as speaker design and special-purpose test equipment design.
Rod Elliott also has done many different things in audio, and has a knack of explaining things very clearly and succinctly.
Nelson Pass*, a man who really made it in audio yet never lost the 'teenager wonder' (his own words) for audio, has a separate site for Pass audio do-it-yourself.
Then of course, the world's largest, most varied and sometimes overwhelming: www.diyaudio.com - every subject, every level, facts and figures and plain bullshit - in other words, just like the real world!
Siegfried Linkwitz wrote to KEF in 1974(!): "This will be the end of my involvement in speaker design" - yeah sure! Championing dipolar speakers with controlled directivety and thus controlled reflections. Worth a browse.
A very prolofic designer who produces a constant stream of unusual but very useful pieces of audio equipment and test equipment: Pete Millet's audio pages also has lots of tube data sheets and assorted facts and figures, and is a gateway to info on books and transformers.
Finally, if you're even a bit like me, you've probably be in a situation at one time or another that you really think you've discovered something New and a Breakthrough. I've been wrong everytime, but maybe you do better. To save you a lot of time, money and aggravation, read The Alternative-Science Respectability Checklist! Really. Do it.