more voltage , more oohmps ;
however , don't go bellow 24 and certainly not more than 30V , without cascoding
in your boots , I would go with 24 , heavily ( read - shunt ) reg-ed
however , don't go bellow 24 and certainly not more than 30V , without cascoding
in your boots , I would go with 24 , heavily ( read - shunt ) reg-ed
But if it is not the same rail as F4, it doesn't matter I can go any way from 24 to 30. It wil be a separate transformer, so what is the best 28V? The only thing is: remember distortion curves Pa posted in his paper? More voltage less THD, right?
He never makes labels and legends for his graphs! Bad I am reviewing papers in different journals, I would change it! 🙂 🙂
He never makes labels and legends for his graphs! Bad I am reviewing papers in different journals, I would change it! 🙂 🙂
I just said - I would go with 24V , regged , as general purpose preamp
28V sounds fine , if F4 is in combination
nice compromise between possible swing and input Jfets dissipation
28V sounds fine , if F4 is in combination
nice compromise between possible swing and input Jfets dissipation
Madisound is having a sale on ClarityCaps. There are several line SA, ESA, MR. How critical a part is this? Anyone think you will hear a difference? 10 mfd SA is ~$10 and they go up from there.
pick your own poison
whatever you do , try MKC ( polycarbonate ) bypass
me , as stubborn , will use Elna Silmic + MKC
in fact - would not use any cap there - would make a servo or something , to keep it DC
whatever you do , try MKC ( polycarbonate ) bypass
me , as stubborn , will use Elna Silmic + MKC
in fact - would not use any cap there - would make a servo or something , to keep it DC
Yes, you will likely hear a difference in caps. It's a fantastic place to experiment and hear what different caps sound like.
Silmic and MKC would probably be awesome, if you can find the Wima MKC. Clarity Caps are very good. Again, use this place to experiment/educate yourself as to how things sound. 🙂
ZM - Can you accept PayPal yet to sell Shunty?
Silmic and MKC would probably be awesome, if you can find the Wima MKC. Clarity Caps are very good. Again, use this place to experiment/educate yourself as to how things sound. 🙂
ZM - Can you accept PayPal yet to sell Shunty?
I'd recommend a Shunty if you can get one; if you can't, you could make make a good sounding regulator using a standard 2 device constant current source and a TL431 configured as a high current shunt regulator - see the data sheet - you could also swap the BJT for a FET - if you do, don't forget to add a 220R gate resistor.
Add a pre reg if you need to drop some voltage, this will also help to reduce the power dissipation in the shunt.
You can flip the symmetry of the pre reg and constant current source for the neg rail, but not the shunt, which won't make a difference to the performance, but some people can get a bit overly anal about symmetry.
Add a pre reg if you need to drop some voltage, this will also help to reduce the power dissipation in the shunt.
You can flip the symmetry of the pre reg and constant current source for the neg rail, but not the shunt, which won't make a difference to the performance, but some people can get a bit overly anal about symmetry.
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With Shunty from ZM, may as well throw in the Pumpkin for best deal. Shunty has a lot of parts, more complex. BA-3 is simple, has few parts, Seems similar treatment on the PSU is warranted.
Shunty is simple , in fact ( same as 
is simple , in fact ) - one simple series pre-reg , CCS , LTP error amp , shunt darlington
is simple , in fact ) - one simple series pre-reg , CCS , LTP error amp , shunt darlington
Sorta...
I agree that the Shunty looks complex by comparison to the BA-3, but it is a known quantity and by all reports works very well. I am wanting to try it.
Yes, you might as well get a Pumpkin PCB at the same time. 🙂 🙂 🙂
I tell you F4 and Pumpkin was a dream pairing!
Soundwise and if I would be more wise, I could have stopped at this point.....!
But the seduction by the new stuff is great, and as a friend said, at this level were are moving with Nelson's suggestions,........ there is often no better, but only a different sound.
Soundwise and if I would be more wise, I could have stopped at this point.....!
But the seduction by the new stuff is great, and as a friend said, at this level were are moving with Nelson's suggestions,........ there is often no better, but only a different sound.
That's what I want to try. And also the ImPasse.
With either of those two preamps, I really want to make a BA-3 output stage (which is essentially a F4) that has the 25v rails, or maybe a bit more (27v?)
Yes, the seduction of always trying and building something new is very strong.
🙂 🙂 🙂
Tea Bag just put up another sign up for the Salas SSLv1.1. Another option for BA-3 preamp psu.
Of course I could use at least 2 preamps; Living room + office...and then there is the shop and the garage...daughter could use a system...🙂
Of course I could use at least 2 preamps; Living room + office...and then there is the shop and the garage...daughter could use a system...🙂
Ut- Oh. I have a BA-3 board and parts. I've been wanting to use the BA-3 as a FE, and had planned to use it with B-1 like Timbarnes did in the previously mentioned post. This thread has me thinking....I also do have a pumkin-shunty board set and all the matched tidbits.....I'm watching this one!
Russellc
Russellc
Use BA-3 front end circuit as driver (attached and in same case) for F4. That way you can have stand-alone (or with selector and pot, integrated) F4 with "normal" gain. You could probably drop the buffer on the F4 as well...
About using the Shunty from Zen Mod for the power supply, was that strictly in reference to the balanced BA-3? I've been wanting to get that power supply up and running. (as well as the Pumpkin) The Timbarnes execution of B-1, BA-3 FE, and F-4 looked like the straightforward way for me to proceed. Yes, some buffers are being duplicated, but it certainly solves any gain problems a B-1 user could face!
I guess just completeing the Pumpkin would solve that as well...
Russellc
I guess just completeing the Pumpkin would solve that as well...
Russellc
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