Completely Symmetrical 32W ALL FET

[lineup]

I have a supplier which can sell:
- 2SK246BL 2SJ103BL complementary JFET
- 2SK216 2SJ79 complementary Lateral MOSFET
- 2SK1058 2SJ162 complementary Lateral MOSFET

So I made a symmetrical design for those. Will give like 32W in 4 Ohm and like 16W in 8 Ohm. I think.

The amplifier is very easy to understand. The R10 and R11 resistors are used to calibrate for 8mA in the input stage. I might even need to change the P2 value. Also R3 and R4 can be necessary to adjust for 50mA in the VAS.

What I want to ask is, if there is any compensation needed? Do I have to put in some capacitors in the circuit?

I am thinking putting 100pF across 2SJ79 and 100pF across 2SK216. Is this the right thing to do? How would you compensate this amplifier?

 

[UltimateX86]

Hi, it look like the grand mos, 10p on driver

http://francis.audio2.pagesperso-orange.fr/Grand_Mos.jpg

 

[UltimateX86]

for input stage http://jm.plantefeve.pagesperso-orange.fr/zenevo.gif

 

[MadInventor]

I have a supplier which can sell:
- 2SK246BL 2SJ103BL complementary JFET
- 2SK216 2SJ79 complementary Lateral MOSFET
- 2SK1058 2SJ162 complementary Lateral MOSFET

What I want to ask is, if there is any compensation needed? Do I have to put in some capacitors in the circuit?

I am thinking putting 100pF across 2SJ79 and 100pF across 2SK216. Is this the right thing to do? How would you compensate this amplifier?

Hello lineup,

First, do you have a camera in my lab? I'm designing a preamp with this front-end, except I'm using Unobtainium J-Fets and a servo, no pot adjust. Speaking of which if I ask you where you get the 2SK216 2SJ79, would you tell me? Start with a 33-47 pf on the 2SK216. The high current in the VAS, is the right way to go.

Later,
MI