Yes. It sound's like a 400W amp to me now
I found the schematics for those interested. I may bypass C1 when time allows.
Cheers.
M.
Thank you for sharing the schematic.
How many amperes you get with -3.4V fix bias ?
What transformer model you use ? Jensen ?
I know Uncle Mike have great experience with 2SK180 and jfet´s impedance buffers
Hi Soundhappy,
I using Lundahl LL1660 10mA with 1:2.25 mode if Im not mistaken.
Surya
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Hi Surya
Ok is this one SE model right not PP ?
http://www.jacmusic.com/lundahl/datasheets/1660.pdf
My is 600:600 impedance similar to Jensen in Mr Pass Sony Vfet CSX1 with the input transformer:
http://www.firstwatt.com/pdf/art_sony_vfet_pt1.pdf
I have good practical experience with 2SK82 amp only you can see :
L'Amp: A simple SIT Amp
With 2SK180 you can try Lundahl and what happen imho
i am sorry can't write you more about ideal configuration and what the best input transformer choice for big Tokin SIT.
simple logic ......
+50V is always +50V
while everything bellow that can always go only lower than +50V
so , positive side of cap to +50V
Thanks you guys for your advices.
Dear ZM, I will try it some day, with my test speakers.
Dear Atma, active CCS will certainly improve voltage swing headroom (and power handling of the output) but, will it sound better? I tend to prefer passive CCS, in fact the inventor of the circuit -ECdesigns- made extensive test with different configurations and decided that this one was better soundwise.... but I will try a cascoded CCS sooner or later. In fact my next move will be cascoding the VFET, as I am a very big fan of cacoding the output, as my new signature suggests.
Dear Surya, I believe it is only 900mA with this "low" voltage PS. I am using a gifted Tx that is perhaps too small for the duty. I might get a more powerful SMPS for the task, as I had good experiences with them together with power regulators.
Cheers,
M.
Dear ZM, I will try it some day, with my test speakers.
Dear Atma, active CCS will certainly improve voltage swing headroom (and power handling of the output) but, will it sound better? I tend to prefer passive CCS, in fact the inventor of the circuit -ECdesigns- made extensive test with different configurations and decided that this one was better soundwise.... but I will try a cascoded CCS sooner or later. In fact my next move will be cascoding the VFET, as I am a very big fan of cacoding the output, as my new signature suggests.
Dear Surya, I believe it is only 900mA with this "low" voltage PS. I am using a gifted Tx that is perhaps too small for the duty. I might get a more powerful SMPS for the task, as I had good experiences with them together with power regulators.
Cheers,
M.
Thanks. You mean like this? I assume they ship with the distal end of the wire electrically accessible?
Essex Magnet Wire 16 AWG Gauge Enameled Copper Wire - 10 LBS - Industrial Rare Earth Magnets - Amazon.com
Essex Magnet Wire 16 AWG Gauge Enameled Copper Wire - 10 LBS - Industrial Rare Earth Magnets - Amazon.com
Like Micheal said a 10lb spool of # 16 wire will be about 100 to 120 mh and 5 to 6 ohms. I believe the 2 I have measure 5.3 ohms. But while that spool of wire does make a nice 100-120 mh inductor as it is the form factor is not all that good. In playing around with this program I calculated using a 2" coil form 1" long you may get almost 190mh from that 10 lb of wire and even that may not be the optium form. But I am too lazy to rewind my coils so will use them as is. Air Core Inductor Designer / Calculator