with the primaries properly wired up for the voltage supply you have the transformer is a 550VA.
If you wire the two 100Vac primaries in series and connect them to a 115Vac supply you reduce the transformer to ~300VA.
DON'T.
Fair point. I was applying Nelson's advice to get the right voltage without thinking about the power capacity of the primary windings. I guess I could use it that way with fewer transistors per side...maybe three or four?
Perhaps an alternative would be to series regulate it down to the required voltage? It would require a pretty hefty series transistor, I guess.
Can I raise the power supply voltage of BA-1?
I'm going to keep my BA-3 with its own power supply, so I'm only concerned about power to the output stage and bias boards.
I want to use my 27+27V transformer, which yields about 38V DC.
It seems that the extra voltage would not burn the power transistors, but I'm not so sure about the bias boards.
Any thoughts?
I'm going to keep my BA-3 with its own power supply, so I'm only concerned about power to the output stage and bias boards.
I want to use my 27+27V transformer, which yields about 38V DC.
It seems that the extra voltage would not burn the power transistors, but I'm not so sure about the bias boards.
Any thoughts?
The output stage of BA1 works in pure single-ended.
With 0.58 A per MOSFET (6), the BA1 provides, with ± 32V, 50 watts into 8 ohms, 25 watts into 4 ohms but only 12 of 2 ohms, ...
Is there a "small" circuit that could push the output stage in class AB (in the style of the Aleph 0, 0s and 1), for at least 50 watts into 4 ohms and 2.
Regards
Darry
With 0.58 A per MOSFET (6), the BA1 provides, with ± 32V, 50 watts into 8 ohms, 25 watts into 4 ohms but only 12 of 2 ohms, ...
Is there a "small" circuit that could push the output stage in class AB (in the style of the Aleph 0, 0s and 1), for at least 50 watts into 4 ohms and 2.
Regards
Darry
Hi Zen,
I am building a BA 1 I have the front end together and tested out ok,now I am confused at how to WIRE the output I got 2 identical boards for ba 1 output stage ,I don't know how to wire them up ,the diagram has 12 fets post#4 my boards have places for 6 so 1 board is N and the other is P correct so far ?can the outs from both boards be connected ? the way it looks they are jumper-ed over in the diagram ,maybe that's where I'm confused.
I would like a diagram or drawing of how to connect/wire them together,I am trying not to live up to my nick,lol Cheers!
Thanks,
No Smoking( a joke on burning up perfectly good parts.)
I am building a BA 1 I have the front end together and tested out ok,now I am confused at how to WIRE the output I got 2 identical boards for ba 1 output stage ,I don't know how to wire them up ,the diagram has 12 fets post#4 my boards have places for 6 so 1 board is N and the other is P correct so far ?can the outs from both boards be connected ? the way it looks they are jumper-ed over in the diagram ,maybe that's where I'm confused.
I would like a diagram or drawing of how to connect/wire them together,I am trying not to live up to my nick,lol Cheers!
Thanks,
No Smoking( a joke on burning up perfectly good parts.)
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no no
its true for Nelson's original 'idea', and schematic
I reckon he had some very huge heatsink cooling in mind
meaning, any big ordinary stereo box with big double heatsinks could be used for a mono amp
but forum version in the store are designed differently
1 output board holds both N and P devices for a mono amp
a very practical solution for bridged setup where you need a complete stereo amp
looking at my own BA2 output boards from the store, outputs are clearly marked with either 'N' or 'P'
UPS !
BA1 have 'N' outputs only
or else I guess you would have BA2 boards
nosmoking, quit smoking, you are confusing me
that would be BA1 boards
seems like it could also be used for BA3, if you want a SE BA3
each board designed/wired to build a mono amp, one output board for 1 mono amp
Here's what the output stage looks like with the front end removed. It
contains the components to bias it.
hey, that is
thanks Nelsonme like to hardwire that one
man you are fast 
mathing resistors amp layout etc
Thanks,
How precise does matching have to be done? Would within 2 percent be sufficient?
Heres's another question
the idea is to build balanced version of ba3 to serve as frontend with powerstage of ba1 (thats the single ended version).
I will build two mono chassis. Each chassis has heatsinks on left and right side.
Am I correct saying that al upper side mosfets (from in fact two ba-1 powerstages) go together on one heatsink and al downside mosfets go together on the other heatsink?
Your advice is again much appriciated
Thanks,
How precise does matching have to be done? Would within 2 percent be sufficient?
Heres's another question
the idea is to build balanced version of ba3 to serve as frontend with powerstage of ba1 (thats the single ended version).
I will build two mono chassis. Each chassis has heatsinks on left and right side.
Am I correct saying that al upper side mosfets (from in fact two ba-1 powerstages) go together on one heatsink and al downside mosfets go together on the other heatsink?
Your advice is again much appriciated
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