I think it would be nice to learn about amplifier history (any type).
To start with a topic:
Does anyone know who built the first class D-type amp? Or who were the pioneers and how did the amps look like?
And when was it combined the first time with a weight sparing SMPS?
I enjoy so much small but efficient amplifiers because of their transportability.
To start with a topic:
Does anyone know who built the first class D-type amp? Or who were the pioneers and how did the amps look like?
And when was it combined the first time with a weight sparing SMPS?
I enjoy so much small but efficient amplifiers because of their transportability.
Well, SMPS makes sense (and the newly adaptive to load variety) when viewed in a large 100 kW! application together with lights, so efficiency is a priority.
Not(e) that a battery operated classD amplifier has some merits compared to a single heater of a tube that absorbs the same current,
About transformers...I do miss the early radios with tandem transistors and interstage/ splitter and load adapter. Also the more powerful variety (class B) with autoformer...
Not(e) that a battery operated classD amplifier has some merits compared to a single heater of a tube that absorbs the same current,
About transformers...I do miss the early radios with tandem transistors and interstage/ splitter and load adapter. Also the more powerful variety (class B) with autoformer...
To my knowledge, the Sinclair X-10 (1964) was the first class-D amplifier actually sold in stores to general public. Too bad it didn't really worked, it seems. It has been cited several times on this forum, see https://www.diyaudio.com/community/threads/component-values-sinclair-x10.301469/
The general idea had been floating around since the '30, see the US patent 1874159, and rediscovered on late '50. Searching on old publications I see that general interest only resurfaced by early '60. Wireless world published an introductory article about this thechnology on the february 1963 issue, page 76; the name "class-D" was not yet coined. The follow-on article on april 1965 issue had the class-D name on the title and there is a picture of the prototype.
The general idea had been floating around since the '30, see the US patent 1874159, and rediscovered on late '50. Searching on old publications I see that general interest only resurfaced by early '60. Wireless world published an introductory article about this thechnology on the february 1963 issue, page 76; the name "class-D" was not yet coined. The follow-on article on april 1965 issue had the class-D name on the title and there is a picture of the prototype.
Sinclair Radionics Ltd produced Class-D (PWM) amplifiers in kit or assembled form back in the 1960s.
The Sinclair X-20 (1965) was much better than it precessor the X-10 (1964): https://rk.nvg.ntnu.no/sinclair/audio/x-20.htm
P.S. This thread exists: https://www.diyaudio.com/community/...ir-x-20-x-10-information.231122/#post-7954160
The Sinclair X-20 (1965) was much better than it precessor the X-10 (1964): https://rk.nvg.ntnu.no/sinclair/audio/x-20.htm
P.S. This thread exists: https://www.diyaudio.com/community/...ir-x-20-x-10-information.231122/#post-7954160
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Are there today similar class d designs without any chips?
I has a sinclair computer and I like to see the sinclair logo again!
I has a sinclair computer and I like to see the sinclair logo again!
I researched this subject a Long while back and found someone that made a Vacuum Tube Class D amp, on the WEB.
It worked pretty good, it was all documented on the builders page, sorry I don't have those links anymore but maybe it can still be found.
I believe there are also a few projects as such and for sure many ads found on the sinclair X10 in some of the older magazines I found at "World Radio History magazines" in that era of about 1958 to 1964. sorry don't remember........
maybe even earlier.....
found here,
https://www.worldradiohistory.com/Radio_Electronics _Master_Page.htm
exactly which one but they are there as I found it one day while I was trying to see what was going on in the electronics world when I got born, and that would be June of 1963 so that would be the place to look as well. 🙂
FWIW. 😉
jer 🙂
P.S. I just found this small discussion on such a device here in this forum, no you got me searchin' for more !! He,he,he
her is a simple schematic on that post above. 🙂
It worked pretty good, it was all documented on the builders page, sorry I don't have those links anymore but maybe it can still be found.
I believe there are also a few projects as such and for sure many ads found on the sinclair X10 in some of the older magazines I found at "World Radio History magazines" in that era of about 1958 to 1964. sorry don't remember........
maybe even earlier.....
found here,
https://www.worldradiohistory.com/Radio_Electronics _Master_Page.htm
exactly which one but they are there as I found it one day while I was trying to see what was going on in the electronics world when I got born, and that would be June of 1963 so that would be the place to look as well. 🙂
FWIW. 😉
jer 🙂
P.S. I just found this small discussion on such a device here in this forum, no you got me searchin' for more !! He,he,he
her is a simple schematic on that post above. 🙂
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Who knows who made the first commercially available class d amps (after sinclair sold PCBs or kits)?
Or which were the companies who produced them in the beginning?
Or which were the companies who produced them in the beginning?
The SONY TA-N88 announced in 1977 and released in 1978 is the first one from a major consumer electronics brand, it had a switching power supply. John Ulrich's SWAMP 1 (for Infinity) was released the year before, in 1976, but it was a niche product. It is likely that special purpose designs may have been built before that.