Isn't that the single ended output stage? Pardon if Imissed something, but I only see IRF P240?
Russellc
Russellc
This was a carefully designed test, and you've successfully passed and not passed at the same time. 🙂 🙁 🙂 🙁
Ok, not really... 😀
This particular schematic is correct, however the lower devices are mis-labeled. Look at the MOSFET symbols, and you can see they are drawn as P-channel. The labels all say 240, but they should be 9240's
Ok, not really... 😀
This particular schematic is correct, however the lower devices are mis-labeled. Look at the MOSFET symbols, and you can see they are drawn as P-channel. The labels all say 240, but they should be 9240's
Hello 6L6
Did you ever built a Ba3 with a no feedback gain stage(the one from this build guide)with a single ended output stage? (the one from here) and if so there is anything else needed to be done differently from this guide (like different size transformer or matched IRPF240's or anything else i can not thing of)?
Did you ever built a Ba3 with a no feedback gain stage(the one from this build guide)with a single ended output stage? (the one from here) and if so there is anything else needed to be done differently from this guide (like different size transformer or matched IRPF240's or anything else i can not thing of)?
Is there anybody that built a 6 pair amp? Would have been nice to have a 4 pair PCB without having to butcher 2 of those 3-pair PCBs. Would be ideal for the 5U/400 case.
Just use the bias boards and point to point the outputs. Or do mono blocks, BBA3 is what I have in mind......A single case might not handle that many without reduced bias? Not sure about that but I will go mono block BBA3 when I do it, already have parts, and the two of the standard Deluxe 5 will do, which I do not have yet. $$$$.
Russellc
Russellc
Yes, I was thinking of 2 BBA3 monos. At this point of time thinking of doing my own cases with better rated heatsinks than what the Hi Fi 200 cases comes with. Just wish they had options for better heatsinks. I am sure Seifert can supply them with some.
Remember that BA-3 (well, the whole series...) is free of global feedback, so much of the performance is counting on having high bias to keep the Mosfet in the linear range.
Bias is good. This is called the "Burning" Amp for a reason. Run it hot.
Bias is good. This is called the "Burning" Amp for a reason. Run it hot.
Yes Jim. You are correct. Running 3 pairs at 500mA bias each will be better than running 6 pairs at 250mA bias each. Would be nice though to have the current for one day when I get my Maggies. But to run 6 pairs at 500mA bias each will require beeeeg heatsinks. But right now my speakers don't require that welder type current.
It's got plenty of current for Maggies... You must remember that the PSU is wildly oversized (2-4x) compared to a typical class-AB amp of similar output. 😀
Hi,
is it possible to use a 2x25V transformer and a bigger resistor in the CRC filter to obtain 32VDC ? Or the smallest resistor value is better ?
Thanks
is it possible to use a 2x25V transformer and a bigger resistor in the CRC filter to obtain 32VDC ? Or the smallest resistor value is better ?
Thanks
25Vac will result in 31Vdc rails , counting on A class loaded rectifier/filter ...... filter being usual CRC , where R is no more than 0R1
Is it ok with a 4U/30cm chassis? Or should I decrease bias. Or should I decrease voltage with a higher R filter to maintain the bias value ?
Hi,
another question...
I got 8 x 47000µF, 4x12000µF and 2x22000µF
Witch CRC config could be better with a 500VA 2x25V transformer ?
small cap --- R --- big cap
or
average cap --- R --- average cap ?
I hope I make myself clear...
Damien
another question...
I got 8 x 47000µF, 4x12000µF and 2x22000µF
Witch CRC config could be better with a 500VA 2x25V transformer ?
small cap --- R --- big cap
or
average cap --- R --- average cap ?
I hope I make myself clear...
Damien
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