bandit2013 said:
Afu, I have been reading up on your posts. Thank you for the information in detail. Brings me back to my days in audio amplifier design. I have been away from that for too long as I spend more time with digital control systems and software development.
I think when I retire I will get back into amplifier design.
Hey, no problem. Before I became disabled, I was building/repairing guitars, building demo amps, and making pedals. I'd forgotten a lot of stuff from school, so I bought several books and read as much information as I could as I got started on the electronics. I contrasted several amps and investigated the developments from the '70s to the '00s, and realized some inaccurate info about the Dual Rectifier.
The people in the DIY pedal community, the AX84 community, and many others inspired me to make anything I found freely available. Since the Recto is a classic amp and is now built differently, I figured the information wouldn't harm Mesa, would be good for students, hobbyists, and tinkerers, and could also be used to make decisions on how to use it. Also, people who want to build a modern amp could use some of the information to make decisions about their own design, not to copy Mesa, but to innovate over the top of it, or to incorporate an idea, even if it is implemented in a different way. I see electronic design as a creative endeavor on par with music or art and ideas should be shared when possible to keep innovation rolling.
(Aside) Steven Johnson has a book and 6 part PBS documentary called "How We Got To Now". It covers how innovation works and how it made modern living possible. I would recommend either one to anyone who creates anything whatsoever. The concepts are illuminating and the stories provide context to illustrate how pieces come together from several sources to make progressive changes, which sometimes completely change our lives within a few steps of change (air conditioning and refrigeration, artificial light, clear glass, etc.). Even "failures" are productive.