Of course all the grounds are connected together and the +9V points are connected together.
This circuit does not have a resistor attenuator at its outputs so it might deafen you. Read the text of its article to see the impedance of their headphones or how they prevent the sound to be too loud.
I'm just using this schematic as a basis so I have an idea where things should go. I'm going to add an attentuator at the output. Which would consist of a couple of resistors, as said before? (Correct me if I'm wrong). I looked at the box for my earbuds, and they are rated at 16 Ohm.
EDIT: I've changed my libraries from this link: here
Much better!
Your circuit has its output capacitors with backwards polarity and is missing the pin 4 connected to ground (0V). Pin 2 does not need a capacitor since it is connected to ground.
Your circuit is missing the very important supply bypass capacitor and the important RC network at each output.
Each amplifier should look like this one as it is shown in the datasheet:
You showed the circuit from the datasheet with bass-boost. Its gain is fine and is shown on the next page of the datasheet.
Then you show an amplifier without bass-boost and a gain of 20 but it is missing the important supply bypass capacitor.
The volume control adjusts the volume from the amplifier. When the amplifier's gain is from 10 to 20 then it will be fine.
The attenuator resistor is selected so that the max sound from your headphones is not too loud. Each set of headphones has a different sensitivity so try a range of resistors.
The Shack did not give me what I needed, and I spent a total of $20. I needed 0.03uF Ceramic Disk Capacitors and got only 0.022uF. I needed 0.05uF Ceramic Disk Capacitors and got only 0.047uF. These wont work will they?
Your circuit does not use any 0.03uF ceramic capacitors. If they are 330nF (0.33uf) input coupling capacitors then they should be film type (not ceramic) and are avaiable at every real electronic parts distributor except RadioShack.
The 0.05uF capacitors in the output RC networks can be 0.047uf.
I'm not going to RadioShack anymore. It costs so much and I've never gotten what I need. Wasn't there a 0.033uF Capacitor next to the 10K Resistor, forming a loop from Pin 1 to the wire leading out of Pin 5 on the Bass Schematic?
EDIT: Also, the 220uF bypass capacitor goes on Pin 7, correct?
EDIT (Again): All the conections that connect to the ground, I can just connec them to the negative battery terminal right?
The bass-boost circuit in the LM386 datasheet shows the "bypass" capacitor at pin 7 to ground. It is 47uF and is needed only when a cheap wall-wart adapter has hum.
The 9V supply needs a 220uF supply bypass capacitor to keep the 9V from jumping all over the place.
If you use 0.022uF for the 0.033uF bass-boost capacitor then the upper bass sounds will also be boosted.
All the grounds connect together and connect to the negative terminal of the battery.
When a battery becomes discharged its internal resistance rises which causes its voltage to fluctuate up and down as the music changes the supply current from it. The supply bypass capacitor smooths the voltage. A good value is the same as the value of the amplifier's output capacitor since the output capacitor's value allows it to feed low frequencies to a high current speaker then the supply bypass capacitor having the same value will smooth the supply's voltage at those low frequencies and will smooth higher frequencies much better.
The amplifier is stereo with two channels. But the fluctuating voltage on the supply voltage is double the frequencies that the amplifier plays. So you don't need a supply bypass capacitor to be double the value of one output capacitor.
I've run into a confusion:
I've bought this board. One side, as seen, has copper rings and one doesn't. Which side is the component side and which side do I solder connections?