Graphic equalizer/bar graph for car

i was thinking about doing a project to get a graphical equalizer and bar graph output to have in a car, i thought this would be a very cool idea but im searching google and i dont think im searching the right thing. the only stuff i found from google were some jukebox website asking similar questions and i only really got 2 decent results, the first was this **broken link removed** but i dont think this is what i want to make the bargraph, am i right in thinking this just works with voltage, it isnt a true graphic equalizer bar graph output. and the other was that connecting a circuit like that to each induvidual band on a graphic equalizer would do the same thing. any ideas on this project or links to site which could help me out, or even the proper name for the bar graph output thing so i can google it

Micro controllers are good at this kind of thing. Feeding a simple intergrating filter into a ADC on a micro controller pin and you cna do anything you want with the LED's.

There's a logarithmic version of the LM3914 - I think that's what you want. I'm assuming you know how to extract the levels for each frequency range ?

connecting a circuit like that to each induvidual band on a graphic equalizer would do the same thing

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Yes, this would do what you described.

proper name for the bar graph output thing so i can google

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Search for "audio spectrum analyzer"

mroberts said:

There's a logarithmic version of the LM3914 - I think that's what you want. I'm assuming you know how to extract the levels for each frequency range ?

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could it be done with some band-pass filters?

mroberts said:

There's a logarithmic version of the LM3914 - I think that's what you want. I'm assuming you know how to extract the levels for each frequency range ?

Click to expand...

For a VU Meter:
An LM3915 is a 3 Db Scaling.
An LM3916 is a -20 to +3 Db Scaling.
Either one will work for this application.

could it be done with some band-pass filters?

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Yup, some band-pass filters, rectifiers/caps and LM3915's. Make as many channels as you want!