You can try the schematic at http://www.audiohobby.com/
Unfortunately because my English is not good so I can't review more....
I built so many amp but until now just only three VFET amps: Sony VFET part 2, Ironamp and VFETRON. The sound of VFET amps is better than other amps so much. About three this VFET amps, the Ironamp is singled end so the taste of the sound is difference; the VFETRON and the VFET P2 are very close but VFET P2 is better about the detail. Until now, I and all of my friends can review the VFET P2 is the best amp I ever made
Hi eduard!
Love to see you, my friend! I love the sound of Mcintosh, I see your amp is a old model but I think the sound still good!
I'm waiting my Lundahl from you...kaka!
I built the amp for my friend, it's use four VFET 2SJ28 with Circlotron topology (it's called VFETRON), the amp running with 23VDC at 1,2A bias. The sound is quite good
Some images and hope all of you love it
Very nice work, (fugly) I like it very much!
Hi Nagini
L shape brackets for Vfet TO-3 are strange and small...do they not run too hot ?
Great build with nice chassais
Congratulations
My L shape brackets are good type so the vfets run not hot
My L shape brackets are good type so the vfets run not hot
T bracket in near future to compare with your actual ones ?
T bracket in near future to compare with your actual ones ?
T bracket is better than L bracket but the best bracket is... without bracket and the transistor mount direct on the heatsink
Conrad Heatsinks - Products
T bracket is better than L bracket but the best bracket is... without bracket and the transistor mount direct on the heatsink
Conrad Heatsinks - Products
Oh yeah
Simple and efficient solution
Thanks for interesting link
Best regards
Last year, I built the VFETRON 20 and that is really a good amp!
Now, I'm trying to build a bigger amp with the same design of VFETRON 20 but use a difference gain transistor, that is 2SK180. In this amp, I used many parts in my stock but I think that is good enough for myself
With secondary 45VAC, the zen V3 active supply regulation give 40VDC with 1.5A bias. The amp run too hot so I can't try the the bias as Mike did (2A) because my heatsink is...
The input use UTC A-20 connect with 1:1 (600:600) ratio without jfet buffer. The system for test:
+ Dayton Audio PS220-8 (96.5dB)
+ DAC ES9018 with IV transformer (600R impedance output)
+ Without preamp
The sound? Wow......... It's very impressive at the first note of the song. I can feel the sound is very strong, especially low frequency is excellence. This is follower amp (current gain) but the gain is enough, so no need to use a preamp.
Unfortunately, I just finish one mono block now. I will try to build the second mono block and after that I will drive with the better loudspeaker (ATC SCM50) and have a correct review
By the way: hi Mike! Now my amp running without two resistors (two resistors connect two output to ground). Can you tell me what happen if I do not use them? Now, my amp have a little hum at loudspeaker, that is the reason I don't use resistors??? Thanks!
Some images..., hope all of you like it
Now, I'm trying to build a bigger amp with the same design of VFETRON 20 but use a difference gain transistor, that is 2SK180. In this amp, I used many parts in my stock but I think that is good enough for myself
With secondary 45VAC, the zen V3 active supply regulation give 40VDC with 1.5A bias. The amp run too hot so I can't try the the bias as Mike did (2A) because my heatsink is...
The input use UTC A-20 connect with 1:1 (600:600) ratio without jfet buffer. The system for test:
+ Dayton Audio PS220-8 (96.5dB)
+ DAC ES9018 with IV transformer (600R impedance output)
+ Without preamp
The sound? Wow......... It's very impressive at the first note of the song
. I can feel the sound is very strong, especially low frequency is excellence. This is follower amp (current gain) but the gain is enough, so no need to use a preamp.Unfortunately, I just finish one mono block now. I will try to build the second mono block and after that I will drive with the better loudspeaker (ATC SCM50) and have a correct review
By the way: hi Mike! Now my amp running without two resistors (two resistors connect two output to ground). Can you tell me what happen if I do not use them? Now, my amp have a little hum at loudspeaker, that is the reason I don't use resistors??? Thanks!
Some images..., hope all of you like it
Wow! Amazing work!
You want to keep those virtual ground resistors in, so we should chase that hum down. What value are you using for those, 100 Ohms?
My amp have no resistors now, I think I will use 100 Ohms for each resistor. In your schematic, two resistors connect two output to ground of input primary, should I connect that virtual ground to the chassic of amp?
Thanks!
Sorry, no such animal exists at this time, though all the missing pieces including bias supplies and buffers can be pulled from Nelson's VFETs Part One. The virtual ground resistors I used were 100R/3W and the transformers were the JT-123-FLCF's (or PCs). There may be more later, but the BAF amp is at the top of the list right now.
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