considering how much we are paying him , we are more than good
He's awash in our tributes! How much more could he ask for?!
Demonstrating that enough garlic and butter can make almost anything taste good.
Agreed, i got to liking snails but introduce them to people as "hot pesto shots"
2SJ28 idea I have been pondering:
What about using it with a ~-120v PSU, as a choke-loaded driver for a SE tube output stage, like a 45 that needs -100v or so on the grid? Could be DC coupled and therefore biased at the 2sj28 source. Need to think about whether the P type vfet would mess up phase of the overall harmonics, and things like that..
Ok, how about a wooden stove PSU??
The branding is perfect for our crowd: DevilWatt ;-)
100W TEG for Wood Stoves, Water-Cooled - By Devil Watt
A moody amp that changes it's own tone as the fire progresses.
The branding is perfect for our crowd: DevilWatt ;-)
100W TEG for Wood Stoves, Water-Cooled - By Devil Watt
A moody amp that changes it's own tone as the fire progresses.
I have been emulating this on Spice. It seems that 200V-300V required to achieve high voltage swing with low distortion. I'm actually planning to build one, so I wish someone can confirm it.
Cool!
I've seen Sony curves up to -240v, not sure on maximums though, have you seen anything on this?
With inspiration from Papa's M2, I was also thinking about a way to deal with the Vfets distortion across so much voltage swing, by using their good gm (compared to tubes): Have a 1:1 IT was wired as a "choke-load autoformer" and you'd get a 1:2 step up and keep the DC coupling therefore the tube biasing
So what I'm thinking is a -140v PSU to one connection of the IT/Autoformer, the Vfet would attach to the midpoint (where each side of the IT is tied together), and the last point goes to the grid. Maybe more than a 2x step up is possible, but there are bifilars out there with 1:1
I've seen Sony curves up to -240v, not sure on maximums though, have you seen anything on this?
With inspiration from Papa's M2, I was also thinking about a way to deal with the Vfets distortion across so much voltage swing, by using their good gm (compared to tubes): Have a 1:1 IT was wired as a "choke-load autoformer" and you'd get a 1:2 step up and keep the DC coupling therefore the tube biasing
So what I'm thinking is a -140v PSU to one connection of the IT/Autoformer, the Vfet would attach to the midpoint (where each side of the IT is tied together), and the last point goes to the grid. Maybe more than a 2x step up is possible, but there are bifilars out there with 1:1
What output tube are you thinking? I meant to mention that the Vfet's higher bias current would be better suited to drive the multiplied capacitance of the grid that the stepup causes.
No comment on A2 and supplying grid current through the autoformer/IT, but I guess it might do just fine
And I should mention that I'm a FirstWatt groupie, so driving tubes is something new for me anyway, in the r&d stage
No comment on A2 and supplying grid current through the autoformer/IT, but I guess it might do just fine
And I should mention that I'm a FirstWatt groupie, so driving tubes is something new for me anyway, in the r&d stage
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My new avatar.
LOL, I almost spit out my Cabernet when I opened this post!!!
Haha starved French eat snails
Soundhappy, regardless of how starved you are, DON'T eat this one!
Single-Ended Sony Vfet amp with four TO-3 per channel design intrigue meI have not seen the curve at high voltage either. I'm sure that MR knows it. I just applied lower voltage LTSPICE curve...
This is the max data from a Japanese page.
2SK82-3
VDGO 240V
VSGO 45V
ID 10A
IG 1A
PT 95W
Tj 120℃
Tsτg -50～+150℃
Actually, my SIT high voltage gain stage plan is not for tube output, but large SIT SE follower output that has a negative gain. It seems that tube CDDA is popular for that purpose, but I would like to challenge All SIT SE amp...
Switchable Output Stage
Speaking of Vfet output stages, I'm working on a CSX, and wondering if anyone has already discussed the similarity between CSX2 (Common source) and the VFET2 (follower) output.
The idea would be to switch the CSX2's 220uF capacitors from the output reference, to the VFET2's front end's ground-reference, and then flip the polarity of the lower transformer coil. It just looks like the topologies were asking for this.
Inspirational pictures attached:
Speaking of Vfet output stages, I'm working on a CSX, and wondering if anyone has already discussed the similarity between CSX2 (Common source) and the VFET2 (follower) output.
The idea would be to switch the CSX2's 220uF capacitors from the output reference, to the VFET2's front end's ground-reference, and then flip the polarity of the lower transformer coil. It just looks like the topologies were asking for this.
Inspirational pictures attached:
Attachments
Yeah but not in amplifiers with SIT-1 or 2SK77B etc. haha
If Zen Mod bring new threads with BC550 audio creativity revolution I stay in tune
Have a nice Sunday
Without jfet's ?
Count me in as well! I met a fellow who has "thousands" of these recently
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