I have no doubt you can put them to use - for the single-ended Class A
followers it is only a matter of picking the best load-line, that is to say
supply voltage, bias current and load. It happens that the 2SJ28 loves
8 ohms, but the 2SJ18 looks to favor 16 or so. Constant current source
for the 2SJ28 at 8 ohms, but maybe some complementary current source
gain or parallel operation with the 2SJ18 into 8 for example.
All anticipated in subsequent offerings. But I would need samples of
the NEC or Hitachi parts....
Fortunately I have many thousands of them.
I’ll probably find a way to ‘glue’ one of these in there. 😉
https://www.mouser.ca/ProductDetail/Infineon-Technologies/IRF250P225?qs=u4fy%2FsgLU9PAwVggMSlGZA%3D%3D
Thanks Pa,
🙂
I have no doubt you can put them to use - for the single-ended Class A
followers it is only a matter of picking the best load-line, that is to say
supply voltage, bias current and load. It happens that the 2SJ28 loves
8 ohms, but the 2SJ18 looks to favor 16 or so. Constant current source
for the 2SJ28 at 8 ohms, but maybe some complementary current source
gain or parallel operation with the 2SJ18 into 8 for example.
All anticipated in subsequent offerings. But I would need samples of
the NEC or Hitachi parts....
I can send a pair of 2SJ20 to you. Shall I send an email to you for the shipping address?
Never used one for audio, probably never will.
My issue is their reliability and what happens when they fail.
In my day job as a Medical engineer, most things use SMPS; when they go bang, they tend to wipe out everything they are connected to. PC's - goodbye data, Ultrasound scanner, goodbye images and £50K's worth of PC & input scanning board, Linear Accelerator - usually over £100K's worth of damage.
Manufacturers don't care, it's extra income for them.
A linear supply failure does not cause that kind if damage, I know what I'll be sticking with.
Nelson, I can send you samples of the Hitachi 2SJ50 / 2SK135 TO3 parts if you like (160V, 7A, 100W)- how many would you need. I have your address - just let me know.
he made F7 with flatpacked ones, so familiar with them
and certainly hawing hundred or two, on shelves
and certainly hawing hundred or two, on shelves
You can also you DiAna - pretty neat piece of software.
DiAna
There is a forum here about it as well.
Fortunately I have many thousands of them.
Once again, I'm wary of getting a beating here. Am I being premature if I look at creating a board that accepts the IRF250 in TO247AC form?
Regards,
Dan 🙂
slim9 this amp is only about 10W into 8 ohms and about 5w into 4 ohms. With your Maggies a 86 db/w 4 ohm speaker I doubt it would be a good choice .
for that, you need scope with 2 channels
one channel showing output signal
second channel showing output signal filtered through so called Notch Filter, which role is to totally filter fundamental frequency of signal you're using (say 1KHz), so you'll see everything else
everything else is what amplifier isn't supposed to produce, and what is producing and you see it that way, is practically distortion itself
of course, distortion being small vs. original signal, sensitivity of second scope channel must be set to higher
and yes, there are also gizmos around called Distortion Magnifier ..... though , I am personally lazy and cheapskate, so will neither buy nor make any of these
besides, it seems only Pa is interested especially in that gigglywiggly, and I must ignore him in at least something
A good (USB) sound card with an PC or laptop , a resistor attenuator, and the Diana software will do!
Look here:
Howto - Distortion Measurements with REW
with the REW software you can measure the normal THD pattern and with
Diana
you see the phase of the residual
DiAna
REW is for PC and Mac available
Diana only for PC
😀
Slim, I am running Maggie LRS panels with ICEpower 500 mono locks and b1 nutube korg in front and am very happy with them. The Maggie’s need power. 🙂
@Bruder
who is going to repair one fuzzy channel of my EMU1212, so I can do that too
QA400 I have, is not exactly helpful, too
who is going to repair one fuzzy channel of my EMU1212, so I can do that too
QA400 I have, is not exactly helpful, too
Anyone who wants to send me vfets / sits can email me. I do not promise to return them, but I will share the data.
Keep in mind that I am
Anyone got the p/n of the Meanwell 36V smps. I think Im fortunate enough to have a small stash of Sony SIT,s from the singapore supplier plus most of the other bits so will be building my own. The kit case is far better than mine though.
I'm not so famous about my good and reasonable decisions, but I think now I letting go off this highly compelling opportunity.
I will not participate in the lottery.
After all, I have two complete Sony DIY VFET amplifier, not so many people have these.
Not to mention other unfinished projects. 😉
So go on, folks!
I will not participate in the lottery.
After all, I have two complete Sony DIY VFET amplifier, not so many people have these.
Not to mention other unfinished projects. 😉
So go on, folks!