Ultimate Pass amp.

[cringvig]

Hi everybody

I am new in here but have been watching for a while

During the years have I been building the A40, A75, Bride of son of zen and B1 Now I am in the situation that I have to built another amp. (The last one if such really exist

I have had the XA 30.5 and I am looking for a sound like the XA 30.5 and the strength of A75, to be honest is it to long ago I have had the A75 to compare it to the XA 30.5 but what is printed in my soul is the feeling of endless power with a total black background.

A very good friend of mine have just finished the BA-3 single ended version and it is just missing something in the voices and upper midrange like everything has been pulled into the speakers again.
I do not know if it is because it is not DC coupled or maybe I am spoiled with the XA 30.5

Then I was looking at the F5 turbo in balanced version but it seems hard to find others who have done this at the moment.

At the moment I think I will go the A75 way but if you guys have other suggestions I am full open.

Have I missed something or is the A75 still the ultimate DIY Pass amp ?

Thanks

Best regards
Chris

[Zen Mod]

what power range you need ?

[cringvig]

Hi

Not much the speakers are these DIY:

http://www.humblehomemadehifi.com/do...Mk-II_copy.pdf

In the area of 30Watt kl. A is fine I think.

I have just ordered the big Hifi2000 cabinet 500mm deep so this is the limit when it comes to heat sink.

The only "problem" with the A75 is that it has to be on all the time in order to perform on its max, I can hear the difference up to a week after cold conditions.
I don´t know if this is the front-end or output stage or both but as I do not have my own new clear power plant in the backyard (yet then my plan was to have it on all the time and then make a relay for decreasing the bias to a minimum when not in use and then let the front-end be warm at all time.

What do you think ?

Thanks

Chris

[Zen Mod]

Originally Posted by cringvig

....... I can hear the difference up to a week after cold conditions.........

What do you think ?

Thanks

Chris

I think you're wakoo

Originally Posted by cringvig

.........
In the area of 30Watt kl. A is fine I think.

......

either F6 or appropriate dimensioned BA-3 ballanced

they're at least my fave in last time , considering your power range

[cringvig]

Wakoo
Carefull mate, you think you are safe behind the curtains but I have visa to go behind the iron curtains

I have not been looking closer to the F6 but as I understand is there a long way for the F5 in the balanced turbo version.

Before was my first choice the BA-3 in balanced version but i am not sure that my head can handle the capacitor in the output of the front-end

Have anyone tried how big difference the capacitor can make in this circuit ?

Br
Chris

[flg]

Further reading of Pass http://en.wikipedia.org/wiki/Nelson_Pass is suggested
https://passlabs.com/technical-articles/
http://www.passdiy.com/projects.htm
Etc...

[cringvig]

??? Because I am putting stupid questions on the board or ?

I mean I don´t throw one line question about "how to" but trying to get input for the selection of the next project.

I am a newbie on the board but I have been building for many years and maybe I could come with some inputs regarding other things or details.

When it comes to the capacitor then I have tried many cheap and expensive in the B1 and just want to know if others had done the same in the BA.

But thanks guys, for the warm welcome.

Chris

[biju55]

why cant you choose Aleph 60 ? .

[sakellogg]

chris. welcome.

i hope the thanks wasnt sarcastic. if so.. welcome anyway.

you asked for opinion so here is my humble one.....
the caps you tryied, did you hear any diffrence? if so and you think it will bother you dont do that amp.

if you have fond memories of A75 and, belive that is the best you have heard, build it.
it will give you a 0 point to compair others to.
you can then build others to compair too.

just for info.....the "last one" dose not exist!

[Zen Mod]

Originally Posted by cringvig

Wakoo
Carefull mate, you think you are safe behind the curtains but I have visa to go behind the iron curtains

I have not been looking closer to the F6 but as I understand is there a long way for the F5 in the balanced turbo version.

Before was my first choice the BA-3 in balanced version but i am not sure that my head can handle the capacitor in the output of the front-end

Have anyone tried how big difference the capacitor can make in this circuit ?

Br
Chris

do not worry - you don't need visa for my neck of wood

whatever - I don't think that you need to worry about cap in signal chain , if BA-3 balanced is in question ; don't be so sure that there are none in XA30.5 , which you cherish

having caps in that sort of circuit (BA3 ball) doesn't do much harm ; nature of the Beast , in fact