Audioguru
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I designed and made a Sound Level Indicator circuit with an LM3915 which is similar to an LM3914. I use a 9V power supply and a 10 ohms 1W resistor feeding the anodes of the LEDs to share the heat with the IC when all 10 LEDs are on. Since the IC outputs have regulated current then diodes are not needed. It has been working continuously for more than 14 years.