name of the game was to create SIT amp for Greedy Boyz Hordes ......
naah, I don't care for Hordes, I have all the fun
logical thing would be to put emulated SIT in same position as in DEFiSIT/SissySIT, which is positive rail; from some reasons I tried in simulations to put it down (lower rail), then realized that that approach is resulting in difficulties - choice of small P channel mosfets for Source follower/level shifter, having low threshold Ugs is much smaller than counterparts in N polarity
however, me being stubborn as I am, stayed with P channel .......
SF Ugs is important, beacuse it is additive to feed point of Schaded mosfet, which in this case we have as -3V8 (ref to output) , then Ugs of TP2640, so resulting biasing voltage at TP2640 gate is around -5V4, ref to output
in same time , Ugs of upper mosfet is +4V42, which means that resistances from rails to adjacent gates are still pretty symmetrical
one of interesting things - of all lately seen amps, only this one is having same current distribution of output parts as real DEFiSIT is having - up to clipping point of more active part, parts are working in antiphase , fighting each other..... and only at and after clipping, lesser acting part ( one with lesser xconductance) is hel;ping other onee
see attached - graph from sim, but confirmed in vivo....... though, easier to post this than capturing scope screen ..... counting on fact that I have a scope from Lee De Forest time, but before triode invention
sim shown from output sine of around 20Vpp @ 8R load
biggest sine - upper mosfet current
smaller sine - current through load
smallest sine - Schaded mosfet current
naah, I don't care for Hordes, I have all the fun
logical thing would be to put emulated SIT in same position as in DEFiSIT/SissySIT, which is positive rail; from some reasons I tried in simulations to put it down (lower rail), then realized that that approach is resulting in difficulties - choice of small P channel mosfets for Source follower/level shifter, having low threshold Ugs is much smaller than counterparts in N polarity
however, me being stubborn as I am, stayed with P channel .......
SF Ugs is important, beacuse it is additive to feed point of Schaded mosfet, which in this case we have as -3V8 (ref to output) , then Ugs of TP2640, so resulting biasing voltage at TP2640 gate is around -5V4, ref to output
in same time , Ugs of upper mosfet is +4V42, which means that resistances from rails to adjacent gates are still pretty symmetrical
one of interesting things - of all lately seen amps, only this one is having same current distribution of output parts as real DEFiSIT is having - up to clipping point of more active part, parts are working in antiphase , fighting each other..... and only at and after clipping, lesser acting part ( one with lesser xconductance) is hel;ping other onee
see attached - graph from sim, but confirmed in vivo....... though, easier to post this than capturing scope screen ..... counting on fact that I have a scope from Lee De Forest time, but before triode invention
sim shown from output sine of around 20Vpp @ 8R load
biggest sine - upper mosfet current
smaller sine - current through load
smallest sine - Schaded mosfet current
Attachments
some funny porn, as proof that I changed something
when I made those few changes from Babelfish M25 R.2 ( few resistors, TP2640), after flipping power switch - Iq came to same value as it was set for B. M25
all what was needed is to correct DC Offset, for 400mV or so
easypeasybreazy
when I made those few changes from Babelfish M25 R.2 ( few resistors, TP2640), after flipping power switch - Iq came to same value as it was set for B. M25
all what was needed is to correct DC Offset, for 400mV or so
easypeasybreazy
Attachments
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How it sounds ...... will it drive F4?
I'm gonna toss all my precious ( 'till today) SITs and VFets to OPLDF bin, cruncher is gonna work these days anyway .....
THD Spectra comparison with SissySIT - go to #7 in SissySIT R.3
I'm gonna toss all my precious ( 'till today) SITs and VFets to OPLDF bin, cruncher is gonna work these days anyway .....
THD Spectra comparison with SissySIT - go to #7 in SissySIT R.3
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5 years ago, it would be revelation and revolution for me
now, reason for satisfied smile
"-is it singing?
-yeah, of course it is singing .... what's there to fuss about"
now, reason for satisfied smile
"-is it singing?
-yeah, of course it is singing .... what's there to fuss about"
more listening today, naturally calmer than yesterday
well, I'm outa here, no more amps for me, what I did ....... I did
well, I'm outa here, no more amps for me, what I did ....... I did
ZM, what's the influence of the input trafo in this circuit?
You loved M2 with the simple Edcor, what about the others?
You loved M2 with the simple Edcor, what about the others?
much more Greenies, little more details
in the end, it is - snatch those you can easier
regarding "simple" ........ behind every decent signal xformer is serious expertise ....... price is sole funny detail when Edcor PC is in case - it is much better product than price is telling
in the end, it is - snatch those you can easier
regarding "simple" ........ behind every decent signal xformer is serious expertise ....... price is sole funny detail when Edcor PC is in case - it is much better product than price is telling
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Yes, those Edcor cost as low as pint of beer in western countries!
Wondering if I'll build this M25.2 to challenge my SissySIT 😕
Wondering if I'll build this M25.2 to challenge my SissySIT 😕
M25 being Cousin to Sissy, even if distant
SET being a Sister to Sissy, no less pretty
surprise, surprise ........
SET being a Sister to Sissy, no less pretty
surprise, surprise ........
LTSpice sez neg
I'm not measuring that:
- QA400 I have can't do that (or I don't know how)
- EMU1212 which I use routinely is having problem with other channel, and you need duplex for Phase
- have no time/will/energy to make/obtain another gadget with notch filtering, even if Pa simply adores comparative wigglywiggly pictures
I simply leave by ear preferred speaker polarity; when I'm in special mood, I even succeed in getting same polarity of both speakers
interesting, LTS is not erring much, comparing to real life
I'm not measuring that:
- QA400 I have can't do that (or I don't know how)
- EMU1212 which I use routinely is having problem with other channel, and you need duplex for Phase
- have no time/will/energy to make/obtain another gadget with notch filtering, even if Pa simply adores comparative wigglywiggly pictures
I simply leave by ear preferred speaker polarity; when I'm in special mood, I even succeed in getting same polarity of both speakers
interesting, LTS is not erring much, comparing to real life
Code:
Harmonic Frequency Fourier Normalized Phase Normalized
Number [Hz] Component Component [degree] Phase [deg]
1 1.000e+03 3.907e+00 1.000e+00 -0.08° 0.00°
2 2.000e+03 4.109e-03 1.052e-03 -89.55° -89.47°
3 3.000e+03 5.531e-04 1.416e-04 7.76° 7.84°
4 4.000e+03 7.574e-05 1.939e-05 95.23° 95.31°
5 5.000e+03 1.130e-05 2.894e-06 -169.54° -169.47°
6 6.000e+03 1.460e-06 3.736e-07 -99.64° -99.56°
7 7.000e+03 2.508e-07 6.420e-08 167.26° 167.33°
8 8.000e+03 3.877e-07 9.925e-08 176.54° 176.62°
9 9.000e+03 3.370e-07 8.627e-08 -179.77° -179.69°
10 1.000e+04 3.027e-07 7.748e-08 -179.90° -179.82°
Total Harmonic Distortion: 0.106158%(0.106159%)
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