Balanced AJ question

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Hello everbody!
After I have read several months, to tell you the truth surely more than a year, I plucked up courage and started this thread, because I have many questions concerning class a amplifiers in general and balanced pass amps in particular.
But before I beginn I would like to say that my english is not so good, that I am able to notice it every time if I alienate somebody.
And although I have read many articles and threads many times i surely didn't get every point. And especially there is a big difference in reading and understanding and doing it on my own. So I'm a greenhorn in diy electronics and will often rely on your kind help.
But what can I do for the diy community? Surely I don't need to mention that I am going to read and learn very much. My plan is to extend my collection on notes and quotes on what is important or essential for diyaudio. And while I build up my amp, I will arrange all the notes and write a documentation on how to build this AJ-X and why, which I give back to the community. This is the least I can do for the diy-community!

Kind regards,
Matthias
 
My plan is to build first the F5 and then the Aleph J-X. I think the F5 is the right one, cause if a caveman could built it, why not me? Then, if I had learned hopefully many things I will take the next stept.
But at first the amp likes to have some power. So the first questions will be concerning the power source.
Here, and just as well in other forums, the opinions about capacitors differ very much.
The first step of learning is to play with duncan's amp tools. So after that it is "only" a matter of how much ripple you like in your power supply. (Here I have assumed to build an unregulated power supply, with CRC or CLC filtering)

(Here I will leave out the question, how high the ripple rejection capability of the Aleph JX is. For the F5 there's a easy sollution: reading the F5 manual. What is good enough for Papa is good enough for me.)

I have read many many pages about capacitory in power supplies, but it doesn't made me wiser. So some people take a few realy big ones others many smaller caps. Beside the nice thing that you can lower ESR and ESL by parallelizing them, are there other pros? What are the pros and cons of big capacitors? (Of course, the more caps you use, the higher is the chance of a failure of one.)

And my most thrilling question:
How can capacitors in power supplies influece the amp's sound?
So, should I buy good industry quality or audiophile caps? You know, you can spend some money on caps but also the worth of a kingdom! But will it sound different?
Do you have any recommendations for me? Are there any caps which are "bad", even though the technical parameters (ESR, I ripple,...) are ok?

So, here I will stop and begin to hit the F5-key impatiently, because I'm really curious about your opinions!

Greetings,
Matthias
 
for first one - best recipe is to follow Papa's work

for F5 and J - difference is in circuit ; everything else - case , PSU - is same

one xformer (2x18Vac 300VA ) , two Graetzs , 8x15mF/25V Pana caps .

if you want better - build dual mono - same PSU , but one per channel
 
Dear Zen Mod,

thank you for your answer! Hm, this makes me brood again about this. I've had the plan to build one power supply to drive the F5 at first and then the Aleph JX. This is why I have planned a bit bigger. But as you say between the lines is right of course: if I don't build Papa's design as close to the original, I won't get a good benchmark to compare later efforts.

Beside this, what capacitors do you have in mind when you think of building an amp for you?

Kind regards,
Matthias
 
if you want to see how I'm making for my self - just look for Papa's Koan thread

in fact - I prefer dedicated xformer for each channel , but I had that big donut with 4 x18Vac secondaries

it will be changed to 2 xformers soon - each one between 300 and 400VA , depending of dimensions
 
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