Help with lm386 and lm3914

I am new to making circuits and electronics so hopefully some of the experts on here can help me

I am trying to build a sound reactive vu meter with the lm386 and lm3914 but I am having trouble with the lm386 and getting it to work with an electret microphone.

When I measure the voltage output of pin 5 from the lm386 I get a constant voltage that doesn't change with different sound levels. Another thing I don't fully understand is what else I need coming off of pin 5 from the lm386. I know I am probably missing some other stuff for the amp so hopefully someone can help me with that.

I have attached the schematic I used to test the lm386 and the schematic with the lm3914. When I know the values the lm386 makes I will calculate what I need for the lm3914 with this awesome tool.


Microphone datasheet: https://www.electro-tech-online.com/custompdfs/2012/02/wm-62c.pdf

Thanks!

Did you mean to use this schematic?

View attachment 61259

Note Pot across electret mic.

Both of you are feeding +4.5VDC to the LM3914 so if all the other pins (4,6,7 and 8) on the LM3914 are connected properly then all LEDs will light all the time. The input to the LM391x should have a 1M resistor to 0V then an input coupling capacitor that blocks the +4.5VDC.

An LM386 is a power amplifier IC thats drive a speaker. An audio opamp like a TL071 should be used as a mic preamp.
An LM3914 is a DC linear voltmeter. LM3915 or LM3916 ICs are logarithmic so are used as VU meters.
Their datasheets explain how to properly use pins 4, 6, 7 and 8.

Thanks, audioguru. A big help, as always.

Wasn't even concerning myself with the LM3915. Duh.

Tritanium, look here.

Thanks for the responses. Looks like I will have to order those parts and some others to get it to work. If anybody has a good schematic that uses a TL071 and an electret mic that would be appreciated so I could also order the parts for that.

Thanks

Here is a preamp for an electret mic. it uses a 470k trimpot to adjust its gain that can be replaced by a fixed 220k, 330k or 470k fixed resistor.