simple solution for VU-Meter

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P { margin-bottom: 0.08in; } I want to add a VU-Meter (older type, analog, not LED) to my 2x20 Watt amp. I'm only interested in pure eye-candy, accuracy of the meter doesn't interest me. With pre-installed rectifier circuit (I hope cheap Ebay models include this) my ideal solution would be...the simplest possable parallel connection to loudspeakers, and I came accross this entry in the forum.....from "djoffe"
http://www.diyaudio.com/forums/solid-state/227309-analog-vu-meter-driver.html
Now I need professional oppinion, if this method works, what values of series resistance would be appropriate? I've read elsewhere that a „Ballistics“ driver is essential...if this is so then I need an absolutely basic op-amp as a buffer. Where would I find a circuit that works on +14.5 Volts? Obliged for any help here, I'm out of my depth.
 
I recently made a PCB layout for the JLM design and it seems to work quite well. The board is mono and measures app. 1.9*1.6".


/U.
 

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Right...great... I'm off to electronic suppliers.
I'll be back.....


P { margin-bottom: 0.08in; }A:link { } Panic! I've bought two VU- Meters from Ebay (see Thumb)
& I think they may be duds. No response when connected to amp input direct and no response when connectted through this basic one-transistor circuit circuit...
http://www.diyaudio.com/forums/analog-line-level/236845-simple-analog-vu-meter-driver.html
…...entry by gpapag. (However, a very fast connection to speaker and the arrow flies to far side of the scale)!
Each picture of a meter that I've seen so far features a long barrel-like enclosure behind...coil and magnet. With these two the extension is quite small (please see pics). Question is, given the dimensions, do these two hold a mechanism or not? If it turns out that the coil-magnet mechanism is just smaller than most and the meters are ok., then I desperately need someone to point me to an alternative basic circuit/driver probably with rectifiers and it needs to work from 14.5 Volts. Please help
 

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If you have a multimeter, switch it to 'OHMS' to measure resistance.
Connect it to the meter and note whether the meter goes up or down.
Reverse the multimeter leads and look at the meter again. If the VU meter goes up with the multimeter connected either way, it's an a.c. meter movement. If the meter 'pegs' to the left with one of the connections, it's a d.c. meter movement. If it's a d.c. movement, why not just feed the meter through a diode (to change the a.c to d.c.)?
 
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