absolutely no
SJEP is enhanced mode device, normally Off, needing positive Ugs to open
linked part is depletion mode device, normally On, needing negative Ugs to close
SJEP is enhanced mode device, normally Off, needing positive Ugs to open
linked part is depletion mode device, normally On, needing negative Ugs to close
I looked a bit at the distortion measurements (MOSFET vs SIT) and tried to make some conclusions.
What I see is that if low output power (1-2 W) then MOSFET shows a little bit lower THD with a bit of 2nd, very little 3rd and then almost nothing else.
The SIT is close but also has a higher harmonic spike so not as clean as the MOSFET?
For high output power (15-25W) the SIT shows much less higher harmonics and lower THD.
Is that conclusion about right?
What I see is that if low output power (1-2 W) then MOSFET shows a little bit lower THD with a bit of 2nd, very little 3rd and then almost nothing else.
The SIT is close but also has a higher harmonic spike so not as clean as the MOSFET?
For high output power (15-25W) the SIT shows much less higher harmonics and lower THD.
Is that conclusion about right?
believe me - whichever you choose to build, if using proper speakers, you'll hardly hear any significant difference
there is difference, but I'm 158% sure - more realm of personal taste than anything else
and, there is a fact - no-one is building FW format amp, thinking of using it in near clipping domain
same as if contemplating how fun is 300B amp in 9W region
there is difference, but I'm 158% sure - more realm of personal taste than anything else
and, there is a fact - no-one is building FW format amp, thinking of using it in near clipping domain
same as if contemplating how fun is 300B amp in 9W region
Yes, we normally listen to 0.01W - 0.5W ....and maybe 5W in peaks if playing loud using sensitive speakers.
My first initial thought was that the pure MOSFET solution looked very good at 1-2 W output power.
My first initial thought was that the pure MOSFET solution looked very good at 1-2 W output power.
I use Lazy Singing Bush mono blocks in the moment in my system and Iron Pre in 12 dB mode as pre. It is hard to believe that this one will sound better.
My two M2X mono blocks is at the shelf. I used DeLuxe 5U chassis for those. Both have 400VA transformers and CRCLC filtering giving about -+23V.
In principle I could take M2X boards out and build this one. 2A Iq will be no problem.
I also have an upgrade kit for the chassis. M3 hex nut rails instead of the old with self cutting screws (some does not "bite" very good anymore).
My two M2X mono blocks is at the shelf. I used DeLuxe 5U chassis for those. Both have 400VA transformers and CRCLC filtering giving about -+23V.
In principle I could take M2X boards out and build this one. 2A Iq will be no problem.
I also have an upgrade kit for the chassis. M3 hex nut rails instead of the old with self cutting screws (some does not "bite" very good anymore).
it's always matter of personal preferences, in context
so, no best amp; only best one for user
as we all know, Best Ever is FW M2
I looked for the F8 article at FW homepage. There was an article going through the amp design and some high level schematics?
Gone?
I have considered trying to raise Iq in M2X to utilize the 5U chassis heatsinks. Like 0.33 ohm source resistors and and use higher value resistor in optocoupler circuit......but that is not a topic for this thread 🙂
I need to take out the M2X boards to modify them and then I could try the F8. I have SJEP120 but why use them when the IRFP150 works so good......
Something to think about.
Gone?
I have considered trying to raise Iq in M2X to utilize the 5U chassis heatsinks. Like 0.33 ohm source resistors and and use higher value resistor in optocoupler circuit......but that is not a topic for this thread 🙂
I need to take out the M2X boards to modify them and then I could try the F8. I have SJEP120 but why use them when the IRFP150 works so good......
Something to think about.
well, best M2 is ......... Babelfish M25
and for different FE, I made Plethora of Pinjatas
but, I like more M25
if you don't try, you'll never know what difference is ........ you'll only know what other sez about that difference
I think it is elegant to use a symmetrical PSU for a single ended output stage to avoid the output capacitor. Most SE amps we see here has an output cap.
Ok....my SJEP is the 120R100 .....not 085.
But why does the SJEP show this 6. harmonic (or 7.)? ........it is some dB down so maybe not to worry about......will see if I can sleep after this...... 🙂
Ok....my SJEP is the 120R100 .....not 085.
But why does the SJEP show this 6. harmonic (or 7.)? ........it is some dB down so maybe not to worry about......will see if I can sleep after this...... 🙂
always take a look at broader picture
in this case, entire set of graphs, and also take in account testing setup - T-Bed deliberatelly less than optimized and tidy
so, glitch at 6K5 hardly being anything else than ........ glitch
in this case, entire set of graphs, and also take in account testing setup - T-Bed deliberatelly less than optimized and tidy
so, glitch at 6K5 hardly being anything else than ........ glitch
better any SJEP than none
so, color me biased, for me SJEP is a SJEP is a SJEP, at least when speaking of amps not working Open-loop
Hi Zen Mod, a question for you on this design. For the input JFet J1 , I have Toshiba 2SJ74BL parts I can use - do you have an optimum Idss current for this Jfet - or preferred Idss range for that position in your design?
Are there any changes, updates etc that we should be aware of?
Are there any changes, updates etc that we should be aware of?
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