I've designed circuit to drive an analog VU meter for my project, but I would like to test it in circuit simulation program before I build it.
Unfortunately, there is no such thing as 'VU meter' in the circuit simulation program that I'm using, so I have to use other components to make something that behaves as close as possible to real VU meter(I guess it's called equivalent circuit).
I'm not sure how to do that.
My first idea was that impedance of VU meter is inductive, so I can approximate VU meter using an inductor.

The reading of the volume indicator shall be 0 VU when it is connected to an AC voltage equal to 1.228 Volts RMS across a 600 ohm resistance (equal to +4 [dBu]) at 1000 cycles per second.

The VU meter and its attenuator should present a 7,500-ohm impedance to the circuit it is applied to, measured with a sinusoid signal that sets the indicator to 0

Inductor that has 7.5k impedance at 1kHz has inductance of approximately 1.19H.
However when I use just 1.19H inductor in place where VU meter would be in my circuit I get rather weird results.

I heard that some meters have integrated rectrifiers, and some doesn't. My circuit is designed for one without integrated rectrifier. So what is the correct way to approximate VU meter?

  • \$\begingroup\$ It must have rectification to get quasi-peak but some rise and fall times desired are your choice \$\endgroup\$ Jun 9, 2020 at 15:58
  • \$\begingroup\$ Would circuitlib.com/index.php/schematics/product/43-needle-vu-meter/… be of any use? \$\endgroup\$
    – Transistor
    Jun 9, 2020 at 16:59
  • \$\begingroup\$ @TonyStewartSunnyskyguyEE75 It has external rectification, I mentioned in my question that my circuit is designed for non-rectifier VU meter type(yes, I know that such meters can't really be called VU meters, but they are just as good for my needs, and significantly cheaper) \$\endgroup\$
    – J K
    Jun 9, 2020 at 17:06
  • \$\begingroup\$ Yeah, I guess rise and fall times are my choice, but I asked how to model VU meter using only basic components that are available in my software. \$\endgroup\$
    – J K
    Jun 9, 2020 at 17:09
  • \$\begingroup\$ @Transistor Well, this article tells me that VU meters are 'based on passive microampere-meters (150μΑ-DC) fed from full-wave diode-rectifiers', which I already know, and show me how to design driver circuit, which I already have. What I don't know is what exactly does 'based' mean, and how to implenent such microampere-meter in simulation software(one again, I'm not interested in actual readings, I just want to be sure that my circuit is working properly and won't add distortion to my audio signal) Thank you for the comment \$\endgroup\$
    – J K
    Jun 9, 2020 at 17:21


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