Well, in principle you can use Patricks variant also with laterals as the 2SK1530 has already really low VGS.
However, don't forget that laterals have much less transconductance, which translates into lower gain and higher output impedance. You need about a pair to get the same values as a single vertical fet; in that case gate capacitances are about the same again (though more linear).
Go for it, if you want.
Have fun, Hannes
However, don't forget that laterals have much less transconductance, which translates into lower gain and higher output impedance. You need about a pair to get the same values as a single vertical fet; in that case gate capacitances are about the same again (though more linear).
Go for it, if you want.
Have fun, Hannes
In principle it should work, though the bias will drift in the other direction (to lower values).
However as I can't open the schematic I cannot give you more help 😉
Have fun, Hannes
However as I can't open the schematic I cannot give you more help 😉
Have fun, Hannes
I'll just give it a go and see what happens..... interesting cct. Have got excess voltage on trannie so might try some rail regs.
The K1058/J162 lateral mosfets aren't quite as beefy as the IRFP240/9240 so you may have to pair them up.
Either double up or get a really big heatsink 
(with an inflation level of 4.5 points and the interest rate undoubtedly dropping a lot lower than yesterday's 6% i hope you've got a very long breath, James)
(with an inflation level of 4.5 points and the interest rate undoubtedly dropping a lot lower than yesterday's 6% i hope you've got a very long breath, James)
Yeah,
It's our turn to do some $ reorganizing, I think - or have it done for us, is more like it.
I'll need a belt with less holes!!
I think the lateral fets will go back in the box, too although the "doa jfet follower" might benefit from something a little different.
It's our turn to do some $ reorganizing, I think - or have it done for us, is more like it.
I'll need a belt with less holes!!
I think the lateral fets will go back in the box, too although the "doa jfet follower" might benefit from something a little different.
Balanced version
Hello
Can someone help me to find the balanced version schematic or maybe the layout for that . I want to find the version which already built by someone and works well .
I have some Toshiba 2SK1529 /2SJ200
Thanks Cheers
Hello
Can someone help me to find the balanced version schematic or maybe the layout for that . I want to find the version which already built by someone and works well .
I have some Toshiba 2SK1529 /2SJ200
Thanks Cheers
jameshillj said:
The only reason they are so expensive on my webstore is that they have been difficult to find, and Newark is even more expensive and was out of stock for over 3 months.
Newark is pretty good, however. I use their MCM division for transistors all the time.
I think you're prices are pretty good actually, particularly the matched sets and the convenience.
Good thing I got those TNC and Slit Foil caps from DNM Audio (excellent caps) a few weeks ago!
Pity there wasn't a magic (and cheap!) source of 220uF/50v BG-NX caps and 10kuF/63v Sikorels!!
Good thing I got those TNC and Slit Foil caps from DNM Audio (excellent caps) a few weeks ago!
Pity there wasn't a magic (and cheap!) source of 220uF/50v BG-NX caps and 10kuF/63v Sikorels!!
balanced version
Sorry 'garborbela' (?), forgot to add this...
There is balanced design started by Tino on post 130 (p6) and further taken up by EUVL on #1186 (p48).
TimS (NZ) also did a design on #135 and continued... (he also did a rather good one for headphones)
Hope this will get you started in the right direction.
Sorry 'garborbela' (?), forgot to add this...
There is balanced design started by Tino on post 130 (p6) and further taken up by EUVL on #1186 (p48).
TimS (NZ) also did a design on #135 and continued... (he also did a rather good one for headphones)
Hope this will get you started in the right direction.
Hello,
Thanks everyone for your answers! I will try to take a look for some other solutions. At the moment I am using this product:
http://www.falco-systems.com/High_voltage_amplifier_WMA-300.html
However, it is only up to +- 150V.
Anyway, thanks to all.
Cheers
Thanks everyone for your answers! I will try to take a look for some other solutions. At the moment I am using this product:
http://www.falco-systems.com/High_voltage_amplifier_WMA-300.html
However, it is only up to +- 150V.
Anyway, thanks to all.
Cheers
Better to wait
Hello
I think for me it will be the best if I wait until Mr N Pass will sare with us the F6 which after some information will be the Balanced verision .
Thanks one more time .
Greetings
Hello
I think for me it will be the best if I wait until Mr N Pass will sare with us the F6 which after some information will be the Balanced verision .
Thanks one more time .
Greetings
Re: Better to wait
If it comes out as anticipated, you had better have LU1014 power jfets on hand or start sourcing some now. The F6 is supposed to be higher power version of F3 I believe.
gaborbela said:
If it comes out as anticipated, you had better have LU1014 power jfets on hand or start sourcing some now. The F6 is supposed to be higher power version of F3 I believe.
The original DAO uses the fets only for the cascodes, so I'm sorry but laterals are of really little benefit in that circuit.
But - of course - feel free to try 😀
Have fun, Hannes
Using 2SK1058 in the DAP follower
Do bear in mind that the LU1014 is being used in "triode" mode, and thus the characteristics of the cascode device plays a more important role than a "penthode" device like normal MOSFETs. I would encourage you to try this, but be prepared to vary the cascode gate voltage AND the source resistor value. In any case, always try to measure Id vs Vgs of the LU1014 directly until you get a linear operating regime. I would guess that you would need to reduce the value of both to get optimal results, due to the lower transconductance (or higher effective resistance) of the 2SK1058.
Or if you have reliable Spice models for both, that would make the initial optimisation a bit easier.
Patrick
PS I propose that we should shift any further discussion to the follower thread.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=128571&pagenumber=3
Do bear in mind that the LU1014 is being used in "triode" mode, and thus the characteristics of the cascode device plays a more important role than a "penthode" device like normal MOSFETs. I would encourage you to try this, but be prepared to vary the cascode gate voltage AND the source resistor value. In any case, always try to measure Id vs Vgs of the LU1014 directly until you get a linear operating regime. I would guess that you would need to reduce the value of both to get optimal results, due to the lower transconductance (or higher effective resistance) of the 2SK1058.
Or if you have reliable Spice models for both, that would make the initial optimisation a bit easier.
Patrick
PS I propose that we should shift any further discussion to the follower thread.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=128571&pagenumber=3
Thanks Hannes, Patrick, for the information.
This little bunch of "critters" has an amazing performance - fascinating - must catch up on the linked thread of the "doa follower + " thread.
Back to the F5.
This little bunch of "critters" has an amazing performance - fascinating - must catch up on the linked thread of the "doa follower + " thread.
Back to the F5.
what's the minimum rail voltage for F5 to operate?
Papa recommend 23V to 25V, but can it operate around at +/- 20V or so?
Papa recommend 23V to 25V, but can it operate around at +/- 20V or so?
it could operate lower, i believe, but remember that the sound changes slightly depending on voltage. the amp with the power supply outlined in the user manual/schema says to use a transformer with dual 18v secondaries, if i recall, which gets you something like 24v rails (is that right? its been a while for me)
-J
-J