[hello im sean]

Hi all, although i can build amps im quite lacking in understanding how they actually work.  I was looking at the AMB Beta 22 designs as i'd like to build one eventually and noticed that the design can use 2, 3, or 4 of the same board for different iterations of the amp.  I think i understand how by adding a 4th board you would get a balanced output as 1 board per channel but how does going from a 2nd to 3rd board only change it from a passive to active ground? Sorry for being so ignorant on all of this but could somebody explain how the Beta 22 works as an amp and works so well?  Or at least direct me to where i can find descriptions of what each piece of it does and how... i know i'm asking a lot but everyone has to learn somewhere. thank you
 
-Sean

 

[deadlylover]

The third board in the 3 board 'active ground' configuration is NOT the same as the other two, in fact, the third board has to be specially configured to serve as the 'active ground'.
 
In the 4 board 'balanced' build, all four boards are identical.
 
Hope that clears it up a little, the article on the beta22 page is great, give it a read or seven.

 

[nikongod]

Tangent's webpage has good info & links to the Jung papers on how 3-channel amps work. 

 

[hello im sean]

ive been reading those AMB pages, theyre great! also who is tangent..? excuse my ignorance
 

 

[liamstrain]

the third board is a shared active ground (both L and R use the same active 3rd board as ground, instead of the passive grounds on their own boards). Balanced is a separate active ground for each one (4 boards).

 

[nikongod]

Tangent is the man. 
http://tangentsoft.net/audio/

 

[hello im sean]

and that helps a ton ^ thank you so much! i was hoping i wouldn't regret making this thread