Can we use this circuit for J2 output stage? http://www.tubecad.com/2009/09/blog0172.htm Pls scroll to Zen Meets the Impedance-Multiplier Circuit
Mr. Pass, any more teasers on the new PL INT-30A...?
Not much to tease. An XA30.5 with an integrated input
system like the INT150.
😎
Item 1. Srajan's photo cleverly made you miscount the
number of JFETs.
Item 2. The 6 legged beast will probably have 8 legs next
board iteration.
Item 3. You already have plenty enough information in
the simplified schematic. Go forth and fill in the details
yourselves.
😎
Perhaps you guys are getting a little too excited. It is not
likely that any of these "more tubey" sorts of parts are
the Holy Grail.
I see them as more of an potential opportunity to get good
sound out of very simple circuits. I certainly am not
trying to emulate tube circuits.
Perhaps I better not mention the two other new depletion
mode parts I got....
😎
number of JFETs.
Item 2. The 6 legged beast will probably have 8 legs next
board iteration.
Item 3. You already have plenty enough information in
the simplified schematic. Go forth and fill in the details
yourselves.
😎
Perhaps you guys are getting a little too excited. It is not
likely that any of these "more tubey" sorts of parts are
the Holy Grail.
I see them as more of an potential opportunity to get good
sound out of very simple circuits. I certainly am not
trying to emulate tube circuits.
Perhaps I better not mention the two other new depletion
mode parts I got....
😎
Can we use this circuit for J2 output stage? http://www.tubecad.com/2009/09/blog0172.htm Pls scroll to Zen Meets the Impedance-Multiplier Circuit
Both of these would be called "mu followers" if you are going
by Wikipedia's examples, and they would work fine, but they
would be J2 variations.
😎
Perhaps I better not mention the two other new depletion
mode parts I got....
😎
Oh maaaaan 🙄
Quasi-Complementary J2
Thanks Ipanema
I have modded the circuit to make a 2 gainstage J2 push pull circuit (quasi-complementary of course), and it works.
I haven't tried to optimise it yet, and I have used Irfp240 because I don't have models of the SiC JFETS yet.
Thanks Ipanema
I have modded the circuit to make a 2 gainstage J2 push pull circuit (quasi-complementary of course), and it works.
I haven't tried to optimise it yet, and I have used Irfp240 because I don't have models of the SiC JFETS yet.
Attachments
Perhaps you guys are getting a little too excited. It is not
likely that any of these "more tubey" sorts of parts are
the Holy Grail.
For me personally this hobby has always been in a way the search for the Holy Grail. I compare the Grail itself with audio equipment, that allows perfect reproduction of music. I don't care about tubes or sand, snakeoil or science or other controversies. I'm searching for perfect sounding music. But will we ever have? Sure!!! 🙂 Compared to the sense of hearing of some animals we humans are quite deaf! 😀 I think there is hope, that the illusion would be perfect some day - at least for our ears. Until then I have fun to occupy myself with this very special search for the Holy Grail. 🙂
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I don't care about tubes or sand, snakeoil or science or other controversies.
Sorry for this edit, nightshift was long and I am a bit tired now:
What I meant to say, I have no preference - neither for tubes nor for solid state. Both are highly welcome to enjoy music. Science is also fine. I have a strong predilection for it. But I hate this quarrel about science or snake oil. Rather often snake oil is pure rip-off! However in some cases snake oil is really effective. The lack of scientific explanation makes it suspicious. Then one day, someone finds the explanation and the whole world cheers: "I always said this!"

Improved parts like these SiC jFETs are always welcome. The advantages have been discussed here and at other places. They are new but quite unsuspicious, because their low distortion is measurable and thus pure science! Are they the Holy Grail? No! Is the J2 the Holy Grail? I hope so! 😛

Thanks Ipanema
I have modded the circuit to make a 2 gainstage J2 push pull circuit (quasi-complementary of course), and it works.
I haven't tried to optimise it yet, and I have used Irfp240 because I don't have models of the SiC JFETS yet.
I need a microscope to read your LT SPICE circuit on my laptop!!!

Sorry about that.
Here is an update on it. The more I tried to optimize it the worse it got, so I have given up on it.
It works quite well with low output but once you get over 15V output it does not look to good.
Here is an update on it. The more I tried to optimize it the worse it got, so I have given up on it.
It works quite well with low output but once you get over 15V output it does not look to good.
The Holy Grail would most likely have very high voltage,
current and wattage ratings. It would have very low and
linear capacitance, and very high and very linear
transconductance, both with respect to Ids and Vds and
temperature (for a FET - substitute other pin designations
for tubes and such).
Complementary versions would be convenient, as well
as depletion mode self-biasing.
😎
current and wattage ratings. It would have very low and
linear capacitance, and very high and very linear
transconductance, both with respect to Ids and Vds and
temperature (for a FET - substitute other pin designations
for tubes and such).
Complementary versions would be convenient, as well
as depletion mode self-biasing.
😎
"Sounds" like V-FETs....
Regarding the Holy Grail of amplifiers and stereo systems I have stopped looking for that. But it is always fun with new and better amplifiers.
On the philioshopical side of it, I doubt the Holy Grail comes in just two channels, but that is probably another thread in another forum in another galaxy far far away.
Also, for the time being, it seems "my" music comes in two, not five point one channels... So no need to worry about center channels or not, LFE mixing and single subwoofers and all this mess.
Vive les deux canales!
RK
Regarding the Holy Grail of amplifiers and stereo systems I have stopped looking for that. But it is always fun with new and better amplifiers.
On the philioshopical side of it, I doubt the Holy Grail comes in just two channels, but that is probably another thread in another forum in another galaxy far far away.
Also, for the time being, it seems "my" music comes in two, not five point one channels... So no need to worry about center channels or not, LFE mixing and single subwoofers and all this mess.
Vive les deux canales!
RK
How about an amplifier and a speaker optimised for every musical instrument used in the music? Forget about an orchestra...just go watch it live!

BTW are your Pumpkin named after the ugly 4.7 uFs http://www.diyaudio.com/forums/attachment.php?s=&postid=1318777&stamp=1191699119 😱
"Sounds" like V-FETs....
I'm not sure we should be referring to them as V-FETs, as
this term would apply to the newer vertical JFETs but also
to our beloved vertical MOSFETs, such as the IRFP240.
In any case, I would like to see better parts yet. The
improvements we have seen lately are accidental
by-products of parts designed for better switching.
The SITs and the Sony parts are interesting for their
dependence on Vds, which allows some cancellation of
second harmonics under ideal conditions but I'm
afraid that this technique has some limitations if you
are looking for the Grail.
😎
And these accidental improvements have resulted in only n-channel devices. I would like p-channels also, but realise for some of us that is not so important.
Please correct me if I am wrong: The so-called V-FETs I am talking about, the Sonys, NECs and Yamahas from the seventies, came before the power MOSFETs as we know them, from first the Hitachi HMA-9600 and the Hafler DH-200 by Borbely a little later (both second half of the seventies). After that the power MOSFET shoved the vertical JFET (V-FET) aside and into oblivion.
Interestingly, the old V-FETs are depletion mode, while the Semi South devices are enhancement mode.
Regarding the grail, let's forget that, and have some more fun! 🙂
RK
Please correct me if I am wrong: The so-called V-FETs I am talking about, the Sonys, NECs and Yamahas from the seventies, came before the power MOSFETs as we know them, from first the Hitachi HMA-9600 and the Hafler DH-200 by Borbely a little later (both second half of the seventies). After that the power MOSFET shoved the vertical JFET (V-FET) aside and into oblivion.
Interestingly, the old V-FETs are depletion mode, while the Semi South devices are enhancement mode.
Regarding the grail, let's forget that, and have some more fun! 🙂
RK
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