VU meter used on preamp out vs speaker out?

Hi, I purchased some Chinese Accuphase clone Vu meters, and contacted the seller and he said they are to be hooked up via the speaker wires.. I am running 3 power amps in a single case (a 3way setup with each channel in a single amp case), and I want to run a single vu meter in each case...vs running 3 vu meters per case. My intention was to hookup the VU meter before my Xikica Crossover and run a cable to each amplifier case to power a single meter for that channel..

Is this possible? How can I do this?

This is the meter I purchased...
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None of your links work :)

Unless there is some addition electronics already included with the meter then you will most like need either a passive rectifier system (not great as they are insensitive) or a simple active circuit using for example an opamp and an 'active rectifier' perhaps with a peak hold function to ensure the meters respond to low signal levels.

They can be calibrated to whatever you wish them to show by altering the gain of the amplifier.

Something like this:

Screenshot 2024-05-12 173118.png
 

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None of your links work :)

Unless there is some addition electronics already included with the meter then you will most like need either a passive rectifier system (not great as they are insensitive) or a simple active circuit using for example an opamp and an 'active rectifier' perhaps with a peak hold function to ensure the meters respond to low signal levels.

They can be calibrated to whatever you wish them to show by altering the gain of the amplifier.

Something like this:

View attachment 1309403
There is a driver board included.
 
Here are pics of the meters and board. Could I use my Nobsound TPA3116 mini stereo amp to drive the meter board?
 

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That board looks a bit different chip wise... maybe the TA7318 is obsolete now and its been redesigned using an opamp. In any case you have to get it all connected and fired up first and see if it all does what you want. It all look like it should do.

that board...could I just run off my preamp...or does it still require a poweramp?
It won't need a power amp but how much signal it needs is an unknown, that is why you have to couple it all up and try it :)
 
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The board needs power and I see AC/DC 12V. The bridge rectifier on the board means it can use either AC or DC and if DC polarity does not matter. I guess High and Low refer to whether you connect to a line level or speaker feed. Ground looks to be common*

You should have instructions supplied with this board.

* if using DC derived from the amp then you really need to figure the board grounds out and see if the power supply ground from the bridge/reservoir cap is the same as the audio ground. That's why you need the correct instructions and/or a circuit of the board. Try powering it with a 9v battery to begin with.
 
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