It is getting to where you can't even build a guitar amp without running into patents on "commonly-known circuits". Randall Smith even has a patent on an interstage attenuator circuit,which is about as old as rocks!! I have no problem with inventors patenting unique circuits,(Like Tom Sholtz did with the resistive loadFUCHSAUDIO wrote:The problem is whether you should bother...I copyright my board art and mark it as such, but it's no guarantee someone can't take pictures or simply start drawing a board up from yours....when I worked at Earth (before most computer PC board programs were in common use) they took Peavey boards and stripped them of parts, made up insertion and part lists, and photographed the artwork to replicate them perfectly. The boards were heavier and higher grade boards since the company was a miltary contractor. They overbuilt except they made mistakes like using unmatched output transistors and made a few fatal shortcuts......
Randall has patented so much prior art it's silly. Things like simul-class and mixing power tube types, different rectifiers, mostly semantics (re-describing prior things differently or with a minor change. The only "real" patent was the channel switching IMHO, which a number of people (Risson, Boogie, Dumble etc) did but Randall patented it. He's bugged a few people (Egnater, Budda, Bad-Cat) over power tube switching and dual rectification, that I know of. He bugged me over diamond plate metal fronts on an amp.
Peavey has had some really innovative patents in solid state stuff. Switch mode amps, solid state emulating tube sound, some cool stuff. As far as tubes go most of the "real" patenting seems to have come from audiophile companies like Audio Research who did some pioneering tube/solid state hybrid stuff that was cool and unique.
The only "small company" I know of that patented something new tube related was Heritages amp division who pulled a patent (via Paul-C's design I think) for a unique output transformer. We shared an attorney who mentioned it, although didn't tell me anything about the details.
Patents and trademarks can run you into money. Most smaller companies would rather take their chances and use the money for something else like IDK, eating....
) but things like switchable rectifiers and switchable cathode fixed bias are IMO taking things a bit too far. What's next, the standby switch And people wonder why boutique amps are so expensive!!...
Tony
People see all his patents on his schematics and think he is some kind of electronics genious when most of the ones I've seen were in books long before he was building amps!..Take a look at Norman Cowhearst's books, (Wrote the book on blocking distortion)..I'll bet you'll find a number of Randall's patents came right out of this book!!..
