Pcb F7 but I can see some resistors
One Pair Firstwatt Pass PCF F7 Power Amplifier Board Bare PCB | eBay
One Pair Firstwatt Pass PCF F7 Power Amplifier Board Bare PCB | eBay
Maybe a dumb question, can we use 2SK1058/162 matched pairs NN/PP in this F7 design (I know matching is optional in the original F7). Looking at all the documentation it seems like apart from the Exicon ECX10P20/N20 even the Hitachi 1058/162 are also good mosfets here.
I am holding on to these Hitachi mosfets for quite sometime for good designs and this seems to be logical considering a FE 🙂
Thanks
I am holding on to these Hitachi mosfets for quite sometime for good designs and this seems to be logical considering a FE 🙂
Thanks
as long you're using Vertical mosfets, you're good
most of them, if not all, having friendly TempCo - decreasing current with temperature, when biased above 100mA
most of them, if not all, having friendly TempCo - decreasing current with temperature, when biased above 100mA
of course!!!
Laterals
sorry, typo/brainfart
while I was checking in ECA Database, I did read 2SK1058 is V type ..... and while I was typing, logical slip
Shure laterals would make biasing easier but didn't Nelson say he didn't like the sound of laterals ?
we all know that he did use them in F7
when Nelson is in case, nothing is carved in stone .......... meaning he likes to make own carvings
🙂
when Nelson is in case, nothing is carved in stone .......... meaning he likes to make own carvings
🙂
Thanks guys, it does say 2SK1058/162 are lateral mosfets but I am not sure if they are the original Hitachi or the newer generation Renesas as I got them long back.
Thanks ZM I will try my hand at building F7 once the current J2 build is completed. Lot of time during the pandemic/lockdown 🙂
is F7 the best sounding amp to use some precious 2SK1058/162 laterals?
Or better to build a cubie2 or cubie3 or something else?
F4 with laterals?
Or better to build a cubie2 or cubie3 or something else?
F4 with laterals?
try avoiding thinking about "the best" for a week, and you'll see that life is suddenly much simpler
Among low-feedback Class A, IMO yes.
The devices have very low gm and are best used with an input stage with plenty of available gain/feedback for the best objective results. I know this isn't the place for objective results but...
The F7 manages to extract quite a lot of performance from these devices, in spite of having low OLG. I can't think of another design that does that so effectively. The Plantfeve amp comes close, but not exactly there.
