So where does one actually buy the 2SJ313 and 2SK2013? I can't find them at Mouser/Digikey/Newark/Allied...
Roscoe
Roscoe
Bit of a gamble on the authenticity on ebay I imagine... Where id Mr Rollins first buy them???
Roscoe
Roscoe
will BA-2 bias curcuit have to be powered from BA-2 power supply ?
or could it be connected to BA-3 frontend power supply ?
maybe a daft question
or could it be connected to BA-3 frontend power supply ?
maybe a daft question
if making my own balanced frontend boards, I thought it might be convenient to place bias curcuit on frontend board
would make it easy to hardwire output stage
It would seem that it still depends on your setup. There are no set rules are there? How many connections from bias board to output board on the DIyAudio store version? What criteria have you failed in your layout?
oh yes, there are
when you begin to draw things, it gets into your head
think of the B2 bias curcuit/board doing the job of the jfets in F5
its the same over again
do not seperate bias curcuit from the outputs
not the first time I would have been told not to
If your talking about putting the bias circuit in a seperate enclosure with FE using seperated PSU then i can see it being a bad idea, but as it stands now, the bias circuit is seperated from tthe output board and need only be placed in same enclosure with same PSU. So, if you wanted to put a custom BA-3 FE with bias onboard in same enclosure with hradwired output stage, i don't see how this would be any different thatn the setup from the DIYAudio store. Perhaps you could explain why it would be.
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absolutely correct
bias curcuit could be placed on frontend board
but according to conclusion, it should still be powered from same supply as output stage
frontend itself could still have its own seperate supply, but not the bias curcuit
whether it makes sense or not
but I'm in doubt about it
right now I might just use additional bank of small supply caps fore the frontend
much simpler
no doubt, Nelson's 'new modular system' means that even the seperate bias board could more easily be replaced by other bias module
its no doubt safer to use the modules on hand in store
and value of amp will no doubt also be higher, and neater
but personally I learn more from trying to change things
that is if it doesn't burst into flames
I hope thats not what burning amps means
but nothing decided yet
other than I have to build it
but balanced is not cheap
need to calculate any possible risks
but hey, its about having fun too 🙂
and I could use another heater during the winter
a highend heater playing nice music 😀
those are the thoughts directly from my confused brain
bias curcuit could be placed on frontend board
but according to conclusion, it should still be powered from same supply as output stage
frontend itself could still have its own seperate supply, but not the bias curcuit
whether it makes sense or not
but I'm in doubt about it
right now I might just use additional bank of small supply caps fore the frontend
much simpler
no doubt, Nelson's 'new modular system' means that even the seperate bias board could more easily be replaced by other bias module
its no doubt safer to use the modules on hand in store
and value of amp will no doubt also be higher, and neater
but personally I learn more from trying to change things
that is if it doesn't burst into flames
I hope thats not what burning amps means
but nothing decided yet
other than I have to build it
but balanced is not cheap
need to calculate any possible risks
but hey, its about having fun too 🙂
and I could use another heater during the winter
a highend heater playing nice music 😀
those are the thoughts directly from my confused brain
I would do what I have suggested and will be doing personally. Put output board and bias boards in main case with Psi and have FE separate in module with connection to both amp and psi.
The bias i think should come up slowly with the output voltage. So it must be connected to those V+ and V-. I would not like to see a big THUMP from fragile speakers. ..
The FE can be powered up & shut down independently of the output stage.
I made various variants of the output stage and FE (what i called the driver then), just connected with two wires.
The FE can be powered up & shut down independently of the output stage.
I made various variants of the output stage and FE (what i called the driver then), just connected with two wires.