ATtiny is the little computer that could. But it’s a lot of work just to drive a simple display element, when a hard-wired chip will do the job well enough.
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Well, my point was that it won’t 
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3914 and 3915 are being sold as DIP on eBay. Whether they will do the job adequately presumably depends on the specifications of the task at hand. If I wanted to design a general purpose tweakable linear or matrix display I’d use a microcontroller too, but that would be more design work, more potential errors and more debugging effort. Sometimes you just want to solder and forget. Sometimes close is good enough.
Edit: since we’re talking about vu-meters I should mention that LM3916 is specifically designed for vu-meter emulation. Here from the link posted further up the thread is a handy video showing the different characteristics of the three NatSemi chips graphically.
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Guess what I found in a box of old spares my GFs dad gave me…
Gonna use the IC and save the stripboard. =D
Theres also a couple other things ive not looked into yet.
2x HCF 4007UBE, RS 4011 BP, LM380N, CD4017BE connected with an RS 4001 B
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You’ll be driving led by meters in no time. 
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You’re not wrong there… 40 leds is more than enough lol
Schem’ nabbed from an infinity mirror design.
EDIT: linked since image transparency makes it hard to see text.
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I used to have a commercial 10 band eq that used a circuit like this one to multiplex a 10x10 LED array. It worked really well but today I would probably use a microcontroller.
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as with the foot pedal controllers in IMO they need to go into the negative voltages , to control / read the modules . the modules work in that range so to be useful the meters / controllers also need to go there . not sure how to do that myself but working on that issue …
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I am totally necroing this. I’m currently trying to figure out how to integrate some 3915s into a buffered multiple.
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Multiplexing the LEDs means that they will be on for a shorter period of time as you increase the number of columns. They will get dimmer but 10 columns seems to work fine. There is a property of your eyes that responds more to the brightest light than to the average light. It will not look 10x as dim as a non-multiplexed display.
I wish I knew more about how to optimize that effect.
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A guy named Eddy Bergamn proposed on his synth blog a cheap oscilloscope (DS138). Maybe it’s a spacey, but could be a cool think on the panel.
Here’s his site: Cheap Oscilloscope
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btw @EddyBergman is also on this forum 
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Hello folks! ^_____^
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Hello Eddy!
Checked all your blog posts 
, maybe adding some of the designs to my mega-project.
Also ordered an oscilloscope from China.
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