For overload protection sensors.Distortion on the edge of the clip. power supply +/ - 30volt
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Maxim, I searched on the net some infos about this type of "current subtraction" approach and I found that only some russian (soviet) amplifiers used this topology. We once lived on the same side of the Iron Curtain, but I did not know that such a great amplifiers were made in the Soviet Union. Of course I knew S90 and S30 loudspeakers (I have had both of them) but never heard the names Corvet and Bark. These are excellent amplifiers. Thanks to Minek who drew our attention to this topology. Honestly, that’s the sound I’ve been looking for for decades. However the amplifiers mentioned above have more complex topology.
Please listen to this video, especially female voices and piano. Awsome.
Корвет 100у 068 - YouTube
Please listen to this video, especially female voices and piano. Awsome.
Корвет 100у 068 - YouTube
The best sound from the Soviet amplifiers the Brig 001. My photo of the Brig and Amphiton-002.Everything is restored
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Oh, I see. Brig 001: opamp input, bootstrapped VAS and tricky non-switching output?
I am really confused which to build 😕 the more posts count in this thread, the more I sink to be honest.
minek says quasi is inferior, not really worth to go with, it was first "Lomakin and Parshin" then "wiederhold", BJT, FET, and suddenly LPK/LMK. I wanted to do FET, I looked at my drawer, I have many BJT and FET, nevertheless 😱
What should I do?
minek says quasi is inferior, not really worth to go with, it was first "Lomakin and Parshin" then "wiederhold", BJT, FET, and suddenly LPK/LMK. I wanted to do FET, I looked at my drawer, I have many BJT and FET, nevertheless 😱
What should I do?
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Check post #39. with Elvee"s 2Si VBE multiplier. Stable, low distortion, and perfect THD profile.
If you want hexfet version, 1st choice would be version from post #235
Unusual amp from 1987
Wiederhold77 with complementary Hexfet (IRFP240/9240).
Perfect for you. It's a sim, not actual build, so no PCB design.
2nd choice would be quasi hexfet from post #259
Unusual amp from 1987
I said it was "supposedly 'inferior'", and 'inferior' is in quotes 🙂
It still gonna be very good amp. Even Maxim built a quasi 🙂
I have a board for it, and the same board can support BJT or Hexfet versions. I have several quasi hexfet amps, and they are great.
That's it for Hexfets.
If you consider BJTs - go for Lomakin and Parshin (1st amp from this thread that I built). Doesn't really matter which biasing you choose (Germanium, single VBE multiplier, or Elvee's). I went for Germanium, and it works like a champ.
I'll give $100 to anyone who will distinguish any of these amps in blind listening test 🙂
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A propos Soviet designs - my 1st project in electronics was
building radio "Звёздочка" when I was a kid 🙂
Звёздочка Star, Swjosdotschka Kit 1st Moskovsky Priborostroi
So I hold certain sentiment to these designs.
building radio "Звёздочка" when I was a kid 🙂
Звёздочка Star, Swjosdotschka Kit 1st Moskovsky Priborostroi
So I hold certain sentiment to these designs.
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HexFetQuasi board almost ready for testing
HexFetQuasi board almost ready for testing.
First time I'm using QFETs: FQA27N25.
Don't have spice model for them - let's see if prototype will
need some compensation tweaking...
Same size and similar layout as the previous LatFet board, but these TO-126 transistors will
need heatsinking.. Drivers will run hotter.
HexFetQuasi board almost ready for testing.
First time I'm using QFETs: FQA27N25.
Don't have spice model for them - let's see if prototype will
need some compensation tweaking...
Same size and similar layout as the previous LatFet board, but these TO-126 transistors will
need heatsinking.. Drivers will run hotter.
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They are 0.33 Ohm resistors.
I wanted to use 0.22 Ohm, but I have them in the wrong size/shape for this board...
I wanted to use 0.22 Ohm, but I have them in the wrong size/shape for this board...
>Resistors should be used with suppressed inductance. Non-inductive
Life is full of necessary compromises... 🙂
If I had them, I would use them..
Life is full of necessary compromises... 🙂
If I had them, I would use them..
WOW, you said you aint build this qhexfet 😀 What has changed your mind 😉
I don't even know what's wrong with quasi 😕
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I'm definitely building quasi hexfet version.
I said I will NOT be building complementary hexfet version (post #235),
which is what most of 'normal' people prefer over quasi design,
and I also won't be building BJT version.
I'm interested only in complementary LatFet (already built),
and quasi HexFet versions.
>If you want hexfet version, 1st choice would be version from post #235
>Unusual amp from 1987
>Wiederhold77 with complementary Hexfet (IRFP240/9240).
>Perfect for you. It's a sim, not actual build, so no PCB design.
I said I will NOT be building complementary hexfet version (post #235),
which is what most of 'normal' people prefer over quasi design,
and I also won't be building BJT version.
I'm interested only in complementary LatFet (already built),
and quasi HexFet versions.
>If you want hexfet version, 1st choice would be version from post #235
>Unusual amp from 1987
>Wiederhold77 with complementary Hexfet (IRFP240/9240).
>Perfect for you. It's a sim, not actual build, so no PCB design.