Balanced Zen Linestage or Holtons Ver

[ajhawkins]

Just wondering if anyone has built either, or preferebly both, i'm going to be building a linestage for a pair of recently completed Leach amps and have narrowed it down to these two. Also anyone have a good source for the 10uf capacitors used...also what type is best...cheapest i found was digikey for about 5 dollars a pop, not ridiculous but a little expensive... any thoughts welcome

thanks,

andy

Anthony Holtons SE Preamp:
http://www.aussieamplifiers.com/se-sch.htm

The bal zen is at passlabs.com

 

[ftorres]

Ajhawkins,

Perhaps you could get best of both worlds using two current sources (one for each Mosfet), and add the mysterious X resistance between the sources of Mosfet

Cheers,

 

[Nelson Pass]

The mysterious X resistance is not the resistor
between the Sources, rather the symmetric
feedback from both sides of a balanced circuit
to the differential inputs.

 

[ftorres]

Oups,

Sorry, Mr Pass. 🙁

In fact, my "mysterious X" did not refer to the supersymetry topology, but to my misunderstanding of this resistance role in the working principle of the differential pair...

I've simulated and built the Balanced Line Stage preamp, and I'm more than happy with it 🙂 (what a sound !!!), but I must admit I'm a complete newbie from the design point of view.

I still can not figure out what is the relationship between the gain and this resistance (that's the meaning of the "X")... I've browsed all the threads on these forums, but perhaps I missed something...

Can someone lend me a helping hand ?

Thanks in advance,

 

[Nelson Pass]

Ah yes, sometimes I forget that the world doesn't
revolve around my own endeavors.....

 

[AudioFreak]

Ah yes, sometimes I forget that the world doesn't
revolve around my own endeavors.....

Almost 🙂 but not quite 🙂