x soz

[stefanobilliani]

I have applied x susy to my soz : simply wonderful

 

[Stefano]

Hi Stefano I'm stefano too, what do you mean? Have you got any schematic? I think that SOZ it's alredy supersimmetrical like BZLS. Please let us know.

 

[stefanobilliani]

Aleph x

Hi Stefano! I have simply look at the aleph x work done by Grey and transpose some parts in a soz front end a little bit modified . Sorry i cannot send any schematic . Also i have not any kind of measure . I 've just feel free to experiment!

 

[ftorres]

Re: Aleph x

Hi Stefano! I have simply look at the aleph x work done by Grey and transpose some parts in a soz front end a little bit modified . Sorry i cannot send any schematic . Also i have not any kind of measure . I 've just feel free to experiment!

Very useful post indeed ! Thanks for the informations, and I will try ASAP to cook mine using your recipe

Thanks again

 

[Nelson Pass]

Congratulations on being the first to publicly mention
the X-Zen. I had thought to perhaps hold this one back
until the Aleph X excitement had died down, but the
cat is now out of the bag.

 

[stefanobilliani]

Nelson Pass and diy .

Thank you mister Nelson Pass.But I have to tell , that day enthusiast took me over! And perhaps i'd need a language translator. I'm talking abouut sonic improvements on Son of zen. I don't know if the topology i use really (- or completly ) takes advantagies from supersimmetry ; but the concepts are there.No operational amps , 2 inputs 2 outputs.Improved stability and output dc offset nearly independent from small variatons of the bias resistors . Maybe only feedback effects ? And sound ... Not find the courage to retourn back to the basic version .Topology is :a soz ( without 1ohm resistor across source pins ) N channel output stage , a differential pair like aleph x ( except drain resistors values ) input stage and feedback from output stage (100Kohm resistor ) + resistor versus ground . I listen to this amp and music are very good and i find that lack of compressions that make the listener play records ... and play ...So at the moment i'm happy .Other <technical> thing are here to say Hope true.Thank you again.

 

[Stefano]

hi Mr. Pass

Hallo, I'm Stefano from Italy, I want to ask you if the BZLS & SOZ are or not quite "supersimmetrical". I'm dreaming to build a BZLS + volume + newest Zen in balanced mode without output caps to use it like an integrated. Tank you for your experience.

 

[Nelson Pass]

Either you guys are very polite, or the idea of an Xzen
is boring, as I expected more response to this.

Polite maybe?

Please note my posting in "Experimental......"

 

[Ian Macmillan]

X-Zen

The idea of an X-Zen is far from boring, though I don't see how it would significantly differ from the Aleph-X concept. I suspect that others simply haven't noticed this post buried in this thread.

 

[Variac]

As Stefanobilliani points out: For a Son of Zen now that's exciting
for Zen : Ho hum
Maybe cause I'm still working on the SOZ!

 

[Michael Rothacher]

Maybe my post is the boring one. I'm the "experimetal design" guy. The circuit I'm working on isn't really an X ZEN - its more of a "two stage class a mosfet circlotron that has potential to be an X circuit" Right now I'm working on the "no overall feedback" version. My thought was to get it working well without gobal feedback, then try to apply super-symmetry. I'm having trouble with it at the moment, so maybe I should abandon it in favor of working up an X ZEN. I was really attached to the idea of an "X-CIRCLOTRON" the name alone sounds cool.

Thanks

Mike

 

[Petter]

XZen is

OK, so since nobody else is jumping into this:

Take an X1000 input stage
Beef up all FET's with the usual Zen types
Lower voltages significantly
Increase current to required level (speaker impedance/power required, voltage ...
Omit output stage ....

You may go to the X100 reverse engineering thread to see schematics you can lift.

Petter

 

[Nelson Pass]

Mike,

A cool name is half the attraction.

The Roger Corman approach:

First you think of a killer name

Then you draw up a really amazing poster

Then you shop is around for distribution

If you get enough distribution, then you make the movie

Please note that Roger Corman made a couple hundred
movies and only lost money on the one featuring
William Shatner.

 

[Ian Macmillan]

X-Zen is...

Originally posted by Petter

Take an X1000 input stage
Beef up all FET's with the usual Zen types
Lower voltages significantly
Increase current to required level (speaker impedance/power required, voltage ...
Omit output stage ....

Assuming you are referring to the folded cascode diff pair (as in the Pass patent) - I am having difficulty squaring this with Nelson's hint:

Originally posted by Nelson Pass

You could explore creation of an X circuit with
a pair of inverting "current feedback" type chips,
if such a thing exists. These would have say a
gate for the negative input and a source for the
positive input. More to the point, you would have
a power inverter on the output stage of each.

Note particularly the mention of power inverter on the output stage. I don't think the folded cascode counts as an inverter, and last time I played around with this idea I couldn't see how to make use of the phase inversion. I ended up using a follower output stage but with the 'Aleph' active current source.

I also tried the circuit without an output stage but found that the gain was excessively effected by the load impedance. Maybe another "trick" is involved. I'll have to get my thinking cap on...

Ian.

 

[Ian Macmillan]

Apologies - I made something of a hash with the quoting in my previous post. Please read carefully to avoid any misunderstanding. I'll try to do better next time.

 

[Nelson Pass]

What I was describing would be a tortured effort at
using IC's to create an X amp. It could be done as a
concept, but who would want to?

All this comes from my original comment that you can't
build X front ends out of op amps as a practical item.

 

[Ian Macmillan]

Ah, so maybe Petter is on the right track. I can see I will have to dig out my notes at trying the folded cascode X front end without output devices. I seem to recall that gain variation with load impedance was the main problem. That and getting sufficient gain with low Z loads.

 

[Michael Rothacher]

The B Movie King!

Nelson:

Would this make you the Stanley Kubrick of audio?

Dr. Pass:
Or, How I Learned To Stop Worrying And Love Source Degeneration

 

[GRollins]

Stefano,
Like so many others, you were caught when I ran out of time to answer e-mail. My apologies. Just to verify that I understood what you posted above...you ended up using a front end?

Grey

 

[Nelson Pass]

My admiration for Kubrick and Corman stems from
creating art on their own terms.

The proper word I believe is *Auteur*

Picasso is another fine example, but not a film maker