Preceding thread here : https://www.diyaudio.com/community/threads/zms-2sk2087c-musings-phase-one-sissysit-as-cradle.386654/
What was logical precursor/reason to dust off schematic I'm having for some time and to implement it in form of new pcbs, arranged so both Tokin Pucks and Tokin 2SK2087 can be used
Novelty - reason enough for playing with, is full DC connection from input to output, and also current-mirrors based biasing circuit
Nota Bene that DC connection between FE and OS is typical Cheating Papaway - anyway, see it by yourself, draw your own conclusions
Changes vs. SissySIT R.3 - none regarding sound (had my time with farting elephants, life is simpler after that), even steadier output DC Offset and Iq stability, vs. time, temperature, mains fluctuation
As I can see, there is some better drive (shown in clipping level for Big One) but these differences are strictly academic ones, sorta pity that this amp is never going to be considered by Audiophools, having all pizzas for great Drek-selling Story
as always, basic pics first
EDIT on 02.02.2023. Last bling, precision CCS moved to separate Daughterboard - post #109 https://www.diyaudio.com/community/...o-sissysit-42-as-a-cradle.387767/post-7256125
What was logical precursor/reason to dust off schematic I'm having for some time and to implement it in form of new pcbs, arranged so both Tokin Pucks and Tokin 2SK2087 can be used
Novelty - reason enough for playing with, is full DC connection from input to output, and also current-mirrors based biasing circuit
Nota Bene that DC connection between FE and OS is typical Cheating Papaway - anyway, see it by yourself, draw your own conclusions
Changes vs. SissySIT R.3 - none regarding sound (had my time with farting elephants, life is simpler after that), even steadier output DC Offset and Iq stability, vs. time, temperature, mains fluctuation
As I can see, there is some better drive (shown in clipping level for Big One) but these differences are strictly academic ones, sorta pity that this amp is never going to be considered by Audiophools, having all pizzas for great Drek-selling Story
as always, basic pics first
EDIT on 02.02.2023. Last bling, precision CCS moved to separate Daughterboard - post #109 https://www.diyaudio.com/community/...o-sissysit-42-as-a-cradle.387767/post-7256125
Attachments
Last edited:
today's funny pics
as you can see, done it all first with THF51S in output, so I can compare measurements of these with measurements with 2SK2087C in place
logically, 2SK2087C in place for second set of measurements
as you can see, done it all first with THF51S in output, so I can compare measurements of these with measurements with 2SK2087C in place
logically, 2SK2087C in place for second set of measurements
Attachments
Now, battery of tests
Will post same measurement of THF51S and 2SK2087C in same post, trying that THF51S is on left side pic; anyway, THF51S related are not having type note, while for 2SK2087C I remembered to include note in caption
go figure
general trend, already established in thread liniked in first post, small one is having lesser THD levels than big one, all the way to clipping , and small one is having lesser power than big one
in all cases - dual rails, 24Vdc-ish, Iq 1A8-ish
1W@8R
Will post same measurement of THF51S and 2SK2087C in same post, trying that THF51S is on left side pic; anyway, THF51S related are not having type note, while for 2SK2087C I remembered to include note in caption
go figure
general trend, already established in thread liniked in first post, small one is having lesser THD levels than big one, all the way to clipping , and small one is having lesser power than big one
in all cases - dual rails, 24Vdc-ish, Iq 1A8-ish
1W@8R
Attachments
So , some conclusion(s) - 2SK2087 is worthy one in SissySIT cradle, whichever revision is in case
Have plans to try it soon in Common Source and Common Drain circuits, both Mu and Choke loaded, very soon; first one should be most likely Warbler, nothing else than choke loaded source follower stage, with all bells and whistles of proper biasing and buffer and yadayada
35Vdc-ish single rail, Iq 3A-ish for Big Tokin, 2A-ish for 2SK2087C
'nuff for today
and yes, it seems SissySIT (42) is now official edition (Caliph instead of Caliph, (42) instead of R.3)
problem is , I'm feeling as living Groundhog Day ...... whatever I'm doing, it always seems as same amp
Iznogood ( Caliph):
Have plans to try it soon in Common Source and Common Drain circuits, both Mu and Choke loaded, very soon; first one should be most likely Warbler, nothing else than choke loaded source follower stage, with all bells and whistles of proper biasing and buffer and yadayada
35Vdc-ish single rail, Iq 3A-ish for Big Tokin, 2A-ish for 2SK2087C
'nuff for today
and yes, it seems SissySIT (42) is now official edition (Caliph instead of Caliph, (42) instead of R.3)
problem is , I'm feeling as living Groundhog Day ...... whatever I'm doing, it always seems as same amp
Iznogood ( Caliph):
