Output stage for BBA3
I'm hammering up a BBA3 and I just realized that I do not have an output stage to mate it with😛
Really just an excuse for finding additional projects😀
Any suggestion anyone? I don't need much power and I don't think I have heat sinks for 300W dissipation.
Cheers,
Nic
I'm hammering up a BBA3 and I just realized that I do not have an output stage to mate it with😛
Really just an excuse for finding additional projects😀
Any suggestion anyone? I don't need much power and I don't think I have heat sinks for 300W dissipation.
Cheers,
Nic
I think the 300W refers to the full six pairs of fets i.e., two output boards per channel. More manageable if you just use one output board per channel.
Chris
Generg,
Have you decided on a position of P3 which you prefer to listen to? If so why do you prefer it?
Chris
A single mosfet pair would mean two pairs or 4 fets per channel for a balanced setup. If you ran two mosfet pairs, that would be 8 per channel and you would need even more dissipation capability than standard BA output.
Standard BA-3 has 3 pairs or six fets per channel. If you look at the schematic for BA-3b, you now have to double that in order to have a complete amp if using standard output stage. Think of BA-3B as a pre-amp and the needed BA output as an F4 running as a mono-block instead of stereo output. Go back and read listing of BA-3B info and look at the output power compared to standard BA amp. That did not come from just different FE. It is a function of the FE and the doubling of the output transistors.
So as long as I run the BA-3 as a single ended design I can still use the single output board is that right?
Just looked at the BA-3b design and I see what you mean.
Chris
Just looked at the BA-3b design and I see what you mean.
Chris
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Nelson Pass BA schematics show 6pair per mono channel
diy store boards were designed to use 3pairs
might be confusing
with the talk now about balanced BA amps, it makes sense
diy store boards were designed to use 3pairs
might be confusing
with the talk now about balanced BA amps, it makes sense
Generg,
Did you see my earlier post? Just wanted your observations on how the BA3 sounded on various P3 settings (or anyone else for that matter).
Did you see my earlier post? Just wanted your observations on how the BA3 sounded on various P3 settings (or anyone else for that matter).
hi Backbones,
the problem is - the Mac software is on a desktop PC (hackintosh) and I put the amps besides it,
when I have in November the software on my laptop (windows software) i can measure and hear in my living room with the speakers, so I have to wait if I prefer more or less k2......
the problem is - the Mac software is on a desktop PC (hackintosh) and I put the amps besides it,
when I have in November the software on my laptop (windows software) i can measure and hear in my living room with the speakers, so I have to wait if I prefer more or less k2......
I might beat you to it by just twiddling P3 one way and then the other--adjusting everything else along the way--and having a listen.
Now I've soldered everything in place can I measure the R value on P3 for different positions (thinks to himself); I'll go down to the garage and see.
Chris
Now I've soldered everything in place can I measure the R value on P3 for different positions (thinks to himself); I'll go down to the garage and see.
Chris
hit me please, hit me, hit me....wasn´t there a song like this 30 years ago?
why are you going to the garage? and was "measuring the R value of R3" a question?
I am very eager to hear if you can hear a difference!!!!!!!!!!!!
good luck!
why are you going to the garage? and was "measuring the R value of R3" a question?
I am very eager to hear if you can hear a difference!!!!!!!!!!!!
good luck!