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LTSpice .wave statement and audio file processing question
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Lucky-Luka:
Hi all
I'm trying to work with the wave statement in my voltage amplifier circuit.
I've read that it works fine for an +-1V output range.
I have +-1V input range and my circuit gain is 10 so this statement doesn't work properly.
How can I properly scale my input signal (a .wav file) in order to get an appropriate output in the +-1V range?
Thanks
iMo:
You may use a resistive divider for example.
Ian.M:
How do you mean your circuit doesn't work properly?

If you want other than 1V max amplitude from a wavefile source, use a wavefile current source (which has max amplitude 1A) with a low value resistor across it, or if you really *NEED* zero output impedance and don't mind a slower sim with a greater probability of convergence problems, buffer a wavefile voltage source with a voltage controlled voltage source (e) and set the gain of the e source to increase or decrease the amplitude.   
Lucky-Luka:

--- Quote from: Ian.M on December 23, 2019, 01:07:51 pm ---How do you mean your circuit doesn't work properly?

If you want other than 1V max amplitude from a wavefile source, use a wavefile current source (which has max amplitude 1A) with a low value resistor across it, or if you really *NEED* zero output impedance and don't mind a slower sim with a greater probability of convergence problems, buffer a wavefile voltage source with a voltage controlled voltage source (e) and set the gain of the e source to increase or decrease the amplitude.

--- End quote ---

In the attached image there is the answer to your question.
I haven't fully understood your second suggested solution but I've applied a voltage divider as imo seggested and I think I've obtained what I was looking for: I have now a max +-1V output signal and the .wave statement works just fine.
Ian.M:
So you want to scale down the output to capture it to a wave file. 
A potential divider works OK for that, as LTspice uses ideal resistors and doesn't add parasitic capacitance  unless you tell it to, so you can use a divider with an impedance several orders of magnitude greater than your circuit's output impedance for negligible loading.  You may need to AC couple the signal to the divider to remove DC offset.   

In real life you may well need to buffer the signal either before or after the potential divider or even both, and if its high impedance parallel a resistive divider with a capacitive divider of the same ratio to swamp the effects of stray capacitance.

However if you want an ideal no load probe with scaling to generate a signal you can record to a wav file, use an E source, or even a BV source if you want to transform the signal mathematically, including subtracting a DC offset.
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