some audio experiments

!!! incorrect !!! stereo depth adjustment circuit
it would work better with VGA(variable gain amplifier) or analog voltage(/signal) multiplier
this one however explains the concept . . . and has a bug (i simplified things here ... a bit too much) -- the sum(avg.) must be reduced when differential is increased and vice versa (the varying resistors should be at the signal inputs - not at the reference inputs at the 3-rd step - and must follow the function that sets their parallel value to the same that the one that goes to the ground = 8 potentiometers connected by the same axle ??? or additional stage to VGA the inputs to correct values . . . whatever)

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teh raight ver.

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a pseudo stereo circuit

https://electronicsproject.org/stereo-simulator/

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[Eop]

µA776/LM4250/LM301 models comparison

differential Sine ::

Note : the max.input voltage range is limited to the half of the half of total supply by common mode variation (e.g. in single sine input the value may be higher !!!)

 µA776 against LM4250 differential Pulse ::

 К(Р)1407УД2 against LM4250 differential Pulse ::

 К(Р)157УД2 against LM301 differential Pulse ::

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NB! -- why there is no Spice models to download here is because i'm not the Spice model factory -- i would rather download these from internet - if there were any - 8 billion people - a lot of Spice users . . . no any g.d. models !!!

mine are not that good that you'd know where or whether to use them and how much or when to trust them -- i don't want to populate chaos ... (there likely is an email somewhere and a comment area if you think you need any)

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[Eop]

some 555 spice models' tests

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inter-model timing differences

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input sink/source currents

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[Eop]

a noise amp test turns out to be a resolute op-amp models' quality checker !!!

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versus

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with one exception ???

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Opto TEST

Analog

Digital :: the circuit is voluntarily interpreted and is illustrative -- further testing must be carried out to implement a working instance of such circuit . . .

a more realistic ver.

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[Eop]