Hello, may I ask what is the PSU and why that big? What about the super regulator, what's the purpose?
Thanks
Thanks
The psu is designed for an output stage, hence a preamp does not need such a powerful psu. I simply reduced the capacity of the single caps and that's it.Superreg is more or less an idealized power source. You don`t need it, but it gives a very clean rail voltage. Very good for a preamp or a DAC.
Oh, ok, I see.
I will probably have an extra Sigma22 PSU with, if I recall correct, about 30V out, it's transformer and would like to get another BA3 board and try and put together a small footprint preamp on my own (the one I had built it is a friend of mine who did it for me), just the BA3 board, PSU, transformer, input selector for two sources and a volume pot, just wondering why the SuperRegulator.
Grazie
I will probably have an extra Sigma22 PSU with, if I recall correct, about 30V out, it's transformer and would like to get another BA3 board and try and put together a small footprint preamp on my own (the one I had built it is a friend of mine who did it for me), just the BA3 board, PSU, transformer, input selector for two sources and a volume pot, just wondering why the SuperRegulator.
Grazie
Ì´ll start from there since I have it on hand. But will reuse it when I build my next output stage.
Agreed...the BA-3FE board only draws 60mA if I remember correctly.
There are a number of PSU's suited for the BA-3, I used the Salas BIB which worked well, but there are others.
There are a number of PSU's suited for the BA-3, I used the Salas BIB which worked well, but there are others.
My experience is it matters and not an imagination. It was. Verified by Paul McGowan of PS Audio too. You can see PS audio CD related products and preamp with oversized toroidal transformers.
Many years ago, I built an opamp based line preamp. First using a small 20VA E-frame transformer with two stage voltage regulator. The preamp must be drawing 20mA at most.
I cannot remember why I decided to change the 20VA transformer with a 500VA toroidal transformer.
The improvements were very significant and definitely I was not imagining. Especially the bass region.
Back then my sound system wasn’t that high resolution so I am sure there are more improvements a high resolution system can review.
I never evaluate to find what is the sweet spot on the how much oversize one can go.
I encourage anyone to give it a try. You may be surprised
I am planning on building a balanced ba3 preamp. I am having a little trouble finding the output MOSFETs. I read in Pass’s guide that having matched MOSFETs is not strictly required. I have found these:
Are these appropriate? Are their values too far apart? What is an acceptable difference in value?
For Sale Thread 'Toshiba 2SK2013/2SJ313'
Are these appropriate? Are their values too far apart? What is an acceptable difference in value?
My understanding of the 2sk2013/2sj313 for the BA3 is they do not need to be matched between the N and the P as the trimpots are there to balance them out. I'm likely incorrect in my understanding, but I find if I make a statement that's incorrect, someone is quick to chime in and correct me.
@tamra is a trusted source from my experience, so you can rest assured you'll get what he's offering.
@tamra is a trusted source from my experience, so you can rest assured you'll get what he's offering.
That is actually pretty similar to how I plan on building mine. I am seriously considering not even including an input selector.
I just (finally) finished a BA3 Pre, partially finished it sat for a few years. I was using Wayne's pre, quite a different sound between the two, both are great, but very different! The BA3, seems more forward? in the mids, and the bass does seem bumped up. Hooked up to an F6, pretty happy, now i need to build an M2X and run two systems, will need a bigger house though .
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Thank you, coming from you it really means something to me. The parts testing, placement, and soldering, I really enjoy, the hard part is after that. The arranging, marking, drilling, and trying to keep it neat can be a dog. There is always a moment I should walk away, but sometimes I don't know it at the time, and that's when I goof, and then have to fix it. That happened here a few times, I didn't take pictures of the goofs though! Thank you for all of your build guides btw, life saving(I really mean that), a picture truly is worth a thousand words sometimes.