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This nifty sound level meter is a perfect one chip replacement for the standard analog meters. It is completely solid state and will never wear out. The whole circuit is based on the LM3915 audio level IC and uses only a few external components. This circuit can also be integrated into audio amp projects.

C112.2uF 25V Electrolytic Capacitor C2, C310.1uF Ceramic Disc Capacitor R1, R321K 1/4W Resistor R2110K 1/4W Resistor R41100K 1/4W Resistor R511M 1/4W Resistor D111N914 Silicon Diode Q112N3906 PNP Transistor LED1-LED1010Standard LED or LED Array U11LM3915 Audio Level IC MISC1Board, Wire, Socket For U1