UAS - Universal Amplification Stage

[lineup]

Yes and it works pretty well for EF output stages.

For CFP, it's more complicated.
Here's a possible solution that I am looking into, for a MOSFET CFP stage (take this as a concept only).
Note the bipolar drivers that can both source and sink current
from the MOSFET gates.

thanks for your schematic example, syn08
I will study a bit more on this cross-conduction issue.
May come useful in some of my future simulation amplifier.

 

[Stee]

Thanks a lot

Hello

I did some test:
the scheme in question works well only with a gain ONE

then the forthcoming experiment will become the cornerstone of Susan:

passive VAS with the transformer
I bought two on ebay for 6C33C ...

coming soon

 

[lineup]

🙂 nice idea Stee
you have great ideas

Passive voltage amplifier stage!!!
using one up-transformation

hehe 😀 will put some headache & questions into some heads here

Lineup

 

[Stee]

Many thanks lineup

but if you don't like transformer...

last orion schematic about Eva
tell me a new idea: The Sequence

(you know Leonardo lives here 20 years)
😱
now I can go to sleep

 

[Stee]

lumanauw lot of thanks

Orion re-edition

 

[lumanauw]

A bit complicated one, but you can see some compensation points.

 

[darian]

Hello,

I'm sorry but what is innovative with that "UAS" design since it's just a conventionnal CFP? What is new? For the GAS, I don't really get the idea : the Vbe is quite unpredictable with bipolars and this one would require some good matching to be ok when idling. And what is the presumed advantage of this rather complicated topology? Any explaination?

 

[Lumba Ogir]

It´s like The Emperor's New Clothes.😀

 

[destroyer X]

Made me think about.... this was the advantage to me

reflections about... was nice to read his brainstorm.

I have accepted Stee invitation to dream with him.... so... i have joined him in this trip... was good to follow his sequence.

Molto benne fratello.

Carlos

 

[Stee]

C & B Complementary and Balanced

thank you very much for your attention

the continuation of this thought around the problem of VSA
( the true footprint of each amplifier )
deviates now in two roads (as happens in every novel)

Research has as its basic criterion as C & B Complementary and Balanced

UAS become an amplifier with passive VSA ... perhaps with Tamura and Mosfets

GAS represents a new sound card that promises emotions from Class A
the new architecture should allow a very harmonious timbre without wasting power (AB Bias)

but at the moment need a test of listening 🙄

 

[Stee]

UAS progress

hello to all

the progress of UAS is this:
transformer have sound of transformer...

better idling VAS with accurate transistor like 2SA1360 and 2SC3423 special for Audio Frequency Amplifier Applications in my SONY

but need a little load...
Collector current IC -->50 mA

so need a mosfet
mosfet can't drive loudspeakers with the "round" sound of bipolar

see the solution

will testing in few days

 

[Stee]

if you like to see base of recent test

http://www.esafono.it/sonytest.jpg

Darian: I don't know, it's just research to found better sound...

 

[Stee]

a new concept of mosfet's job

mosfet have to reduce load on VAS
just to have more accuracy on it
final must be a bipolar

 

[Stee]

UAS version 7

at last

to avoid strange emphasis in VAS
it becomes necessary to minimize the current game
(transistors are much more similar as smaller)

then a spontaneous stage after the VAS done with mosfets

UAS suitable impedance so simple and effective - tested OK
(10K resistors on 25V dual)

 

[Stee]

7 is last version - thanks at all

typical application

 

[Stee]

nice this?

let a small advertising

 

[lineup]

Very good!

at last

to avoid strange emphasis in VAS
it becomes necessary to minimize the current game
(transistors are much more similar as smaller)

then a spontaneous stage after the VAS done with mosfets

UAS suitable impedance so simple and effective - tested OK
(10K resistors on 25V dual)

typical application

let a small advertising

Stefano
Very good ... bella grafica ... bono!
Love your images and graphics.


lineup
Lineup amplificadores fora - solo pro membres
----------------
hehe hehe

 

[Stee]

grazie 1000

see another good modification to reduce load on VAS
and have true hi-end sound

http://www.esafono.it/mark331sch.jpg

http://www.esafono.it/mark331.jpg

never tested until comes mosfets by mail

 

[lineup]

2SK213, 214, 215 216
2SJ76, 77,78,79
= Hitachi best lateral mosfet 😎 😎 😎 😎 😎 😎

My favora favor favourite transistors

HITACHI Data download from LineupAudio
http://lineupaudio.freehostia.com/pdf/contents.php
password = diyaudio
😉
Also visit the new audio forum with members join:
Lineup Audio forum
.

 

[Stee]

The secret of good amplification

I have tested A700 from Lite (china - DIY Gene)
very good sound (thanks Mark)
schematic here http://www.esafono.it/a700.pdf

so my idea now is separate function

a- differential for correction error between demand
better use an OPA

b- voltage amplification
better use small transistors
mirror less

c- current amplification
better use a chain to 3 copules of final device
that does not lead to load the VAS

d- DC servo
important separate because viceversa compress signal