UAS - Universal Amplification Stage

[Stee]

Hello to All

I will present my recent idea - the UAS

This amplifier has the ability to govern themselves alone
thanks to local feedback on output resistors

it's esoteric because ultra simple
it's complementary
can build in chain with different power

need matching devices
do not need adjustment
have gain in voltage and in current

can use LED for biasing
between pre and final stages better put a potentiometer
its natural evolution provides the drive with mosfets

do you think it's intresting?
never tested

[janneman]

Is this supposed to be used as a power buffer because of the gain of one? As the output stage of a power amp?

One potential problem would be the output DC offset.

Jan Didden

[Stee]

Regards

[Stee]

now you can see
at the same time there is :

VOLTAGE GAIN

DC offset control
Thermal drift biasing
Negative feedback subtraction

[Guthorst]

It will have very high THD because of the full class B bias setting.
And there is NO negative feedback.

regards,
Guthorst

[Stee]

I have edited with double input diode

please write on schematic your modification

[lineup]

you can add one film capacitor
across those 2 input diodes
... from base to base of input transistors

will act as a sort of BOOTSTRAP
something like 1 uF would maybe be suitable

otherwise I think your amplifier is a very nice idea
more creative and interesting
than most I can discover at this board from other posters

[janneman]

Originally posted by Guthorst
It will have very high THD because of the full class B bias setting.
And there is NO negative feedback.

regards,
Guthorst

... but there is a LOT of nfb. And the biasing is probably class AB. But that's easy to set with some resistor values.

My question is more, what's 'universal' about this?

Jan Didden

[Stee]

I called Universal
because as for OPA
is a model that you can repeat the same at every level of power

does not require settings - so it is configured with a standard, perhaps an integrated

also evades the tradition that wants to always be the mirror of current in input
bias control in VAS
and the output stage only in current gain

also has the ambition to become globally esoteric
because extremely simple (perhaps sounds good)
you may have to hold a conference to AES in New York...

the only new idea (I think)
is to use a shunt to monitor the current on each branch
in very short rings

I hope also become Universal with your contribution
maybe a good idea use FET/Mosfet in input...

Regards and Thanks

Hi lineup
thanks a lot for your support
this 1uF film capacitor from base to base it's for RF filter?

[Eva]

This circuit has been in use for the past 30 years. There is nothing innovative in it. Its main drawback is cross-conduction at high frequencies.