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I'm trying to simulate an audio vumeter, using an audio amplifier built with a LM386. However, when I connect the output of the signal to the input of one of the opamps (I'm using LM358), the outputs are all negative.

Here is the circuit before the simulation

Here is the circuit while simulation is running

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    \$\begingroup\$ Positive (non-inverting) input of all opamps are tied together, but they're not tied to any known voltage source. i.e. they're all "floating" \$\endgroup\$
    – Kyle B
    Commented Nov 30, 2022 at 20:18
  • \$\begingroup\$ You forgot to connect 'Vout' over to all the opamps. \$\endgroup\$
    – brhans
    Commented Nov 30, 2022 at 21:02
  • \$\begingroup\$ I guess once the op amps are driven with the speaker signal, the first LED will light when loud, and the difference between last two lighted or not will be barely audible. \$\endgroup\$
    – greybeard
    Commented 19 hours ago

1 Answer 1

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You are not sending any voltage signal to the comparators. Thus they won't show anything with no input.

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