A transistor Vbe multiplier would work in place of the 431 and it would adjust in the normal way to set the output stage bias.
However, if the BA-3 FE with was direct coupled to the output stage as described above (I guess we shouldn't be having this discussion without a schematic) then you would have to use the P1 and P2 pots in the FE to adjust the final output stage offset. P1 and P2 would then be adjusting the 2013/313 bias and the final output offset interactively. The temperature performance of the 2013/313 pair could potentially affect the output offset drift more than one might want. This would need some experimentation to find out what the drift performance would be like.
gl
However, if the BA-3 FE with was direct coupled to the output stage as described above (I guess we shouldn't be having this discussion without a schematic) then you would have to use the P1 and P2 pots in the FE to adjust the final output stage offset. P1 and P2 would then be adjusting the 2013/313 bias and the final output offset interactively. The temperature performance of the 2013/313 pair could potentially affect the output offset drift more than one might want. This would need some experimentation to find out what the drift performance would be like.
gl
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I'm using Toshiba's 4.2V, maybe, 200mW maybe, with H.S. probably
Really? I think it will, and output offset too??? The real question is the overall stability?
I didn"t get there yet. I stopped hear first, honestly, I would have forgotten if I didn'come back here...
Well, ther is the capability of leaving it floating (with a little H.S,), but, what will work or sound better?
Thx, I have to many projects at the moment to acually get back to my BA-3 FE.
I assume this offers greater conrtrol and performance? Perhaps temperature compensation if proper componenet is used?
for greater control and performance - dunno .... depending with what you're comparing it 
I'm just saying that you can put appropriate resistor in parallel with entire TL431 based voltage reg , if you need greater amount of current through said reg .
it will worsen (slightly) voltage regulation , but - if you need to implement that vertical string in output vertical of some FE (say that that vertical is made of two opposite mosfets ) , with goal to exclude series connected caps ........ then that's neat solution
temp compensation ....... Papa made some components fashionable lately ......... sometimes you can choose plain NTC for said purpose
I remember Babowana was first Greedy Boy , testing NTC's in some Zen project
edit: I did exactly that (resistor in parallel with 431 circ) drawing some funny Babelfish XA 30.5 amp , with goal to have it :
1.Babelfish as always
2.DC coupled all the way
....... but never had enough interest to try it .
it will work , so ...... it isn't interesting anymore
I'm just saying that you can put appropriate resistor in parallel with entire TL431 based voltage reg , if you need greater amount of current through said reg .
it will worsen (slightly) voltage regulation , but - if you need to implement that vertical string in output vertical of some FE (say that that vertical is made of two opposite mosfets ) , with goal to exclude series connected caps ........ then that's neat solution
temp compensation ....... Papa made some components fashionable lately .........
sometimes you can choose plain NTC for said purposeI remember Babowana was first Greedy Boy , testing NTC's in some Zen project
edit: I did exactly that (resistor in parallel with 431 circ) drawing some funny Babelfish XA 30.5 amp , with goal to have it :
1.Babelfish as always
2.DC coupled all the way
....... but never had enough interest to try it .
it will work , so ...... it isn't interesting anymore
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And here is the distortion vs equivalent output wattage for two values
of supply rails, and compared with the BA-3.
I think you can clearly see the lower distortion and higher power.
Hey Nelson
What were these 2 amps biased at?
Panasonic FC also have iron leads. So probably worrying over nothing.
Elna Silmic do not have iron leads but will not fit on the board.
They will, but it is TIGHT!....and kinda odd looking. Ended up with Nichicon KZ, which is still tight. Should have used 35V caps instead of 50. THat would have helped.
'iron leads' ? I hope they do not rust could you specify 'iron leads'
man, I know we prefer copper, absolutely
but guys, there are all sorts of metal everywhere in your amps
you worry too much, and all you get is headackes
just use whatever possible
in a year you have forgot about it anyway
could you specify 'iron leads' man, I know we prefer copper, absolutely
but guys, there are all sorts of metal everywhere in your amps
you worry too much, and all you get is headackes
just use whatever possible
in a year you have forgot about it anyway
Hi,
I am going to order the boards for a balanced Ba-3 I need the front end board (BAGSv2.0&BASB z2.0) and a output board (BaCb v2.0 &Bacov 2.0)
Right so It says these are 2 chanels so the (BAGSv2.0&BASB z2.0) board has + in and - in one chanel in,so 1 channel, V + and V- is power supply in,Now here's where I need the help,lol the D+ needs one board like the ba output stage D- needs another output stage,I see the power in ,But what is D and out? and on the front board I have D+ D-,and S where do these connect ? D+ I see And this tells me I need 4 output stages and 2 input stages for L&R stereo?
I know I am suppose to be getting smarter at this but too many boards and too many names for them,I was ok until we got off ba-1 ba-2 ba-3, BBA,
Thanks alot,
Ns
I am going to order the boards for a balanced Ba-3 I need the front end board (BAGSv2.0&BASB z2.0) and a output board (BaCb v2.0 &Bacov 2.0)
Right so It says these are 2 chanels so the (BAGSv2.0&BASB z2.0) board has + in and - in one chanel in,so 1 channel, V + and V- is power supply in,Now here's where I need the help,lol the D+ needs one board like the ba output stage D- needs another output stage,I see the power in ,But what is D and out? and on the front board I have D+ D-,and S where do these connect ? D+ I see And this tells me I need 4 output stages and 2 input stages for L&R stereo?
I know I am suppose to be getting smarter at this but too many boards and too many names for them,I was ok until we got off ba-1 ba-2 ba-3, BBA,
Thanks alot,
Ns