samtechpro

you probably made wrong connections. Try rebuilding it.

yes it would overdrive your headphones. You need to build additional circuit to attached your headphones. Here is the link to what you need.https://samtechpro.blogspot.com/2014/03/how-to-use-speaker-output-for.html

Hello brother, you need to have winrar application installed on your PC. It is used to ectract the rar files.

You need winrar to unpack the file first.

If you're asking about arduino sketch where you're getting error on compiling the code. Let me know which error you get. Then i could possibly give you a solution. Second thing if you are using another arduino source code(sketch) share it to me, so that would be easy for me understand and fix the issue.

They can only share c4. And yes this amp can overdrive headphones and create distortion. There are couple of ways for using it with headphones like limit input with a big resistor like 47K. This resistor will be at input of the chip 386. Otherwise you can take a look at this article which shows how you convert any amplifier output to headphones output.https://samtechpro.blogspot.com/2014/03/how-to-use-speaker-output-for.html

Thanks. I wanted to add more as i had much more data about this. Wanted to share all experience i had in building it. But still missed several things. I decided to cover them in a video soon. Anyways thanks for taking your precious time to feedback this post. This means alot..

Yes if you need to make a stereo amplifier then there must be another amplifier for that channel and speaker with the common ground of this amplifier.

Yes a 330uf if blown can cause the hum but many times the hum comes from the mains as you mentioned that you are using an adapter for that. To prevent this put another capacitor of big value like 1000-4700uf between pin6 and ground. This will kill the main hum. And also check out my latest post that contains simple and good modification of this circuit will provide you cleanest sound possible.

Yes you can build separate amp for the other speaker. The ground wire is the common wire. You assemble the circuit board and connect all grounds together. And as you know that it is working on the battery (which generally means) singal supply. So here the ground common point will be considered as the -ve of your battery. And so the input has ground too which is a common point in audio signal. For example if you are using a 3.5mm stereo jack then you may know that it has three points on its pin jack. The tip of it is 1st channel say right and the center one is left so the remaining one is ground what you can connect with this amp's ground terminal.

3) The polarities are not given for the non-polarized capacitors. because the capacitors you're talking about are ceramic type and they don't have that polarity they can be connected in any direction.4) Yes triangular symbol is a general symbol of common ground.

I have a better idea to have more ouput power so we can drive larger speaker of about 2.5inches also the schematic is so simple that any one would feel relaxed to build that. I'll share it within two days on my instructables. And no you should not use AA batteries with 9v supply in order to have 12v. The above circuit and most of the op-amps circuit starts working on 5v. So i think 9v is ok for that you don't need to have 12v special supply. But i would suggest you to keep every suppy because you're gonna need them to test your equipments or you can build your own variable power supply. Have a good day (Y)

The 47nf in the schematic is 0.047uF and 473 is the code of the capacitor

i think 0.047uF is the capacitor you're talking about. And the exact value is 0.047uF and 473 is the code of the capacitor in the ceremic shape.

should be 0.5W max

Yes, you can use it as a pre-amp. You can plug your guitar on its input. Then its (pre-amp) output should be connected to your speakers (with built in amp) or amplifier, If it is an electric guitar. I hope that your guitar has a magnetic pickup. If it has peizo pickup then you need to try my high impedance pre-amp circuit that can be found here:http://samtechpro.blogspot.com/2013/12/build-preamp-for-piezo-pickupcrystal.html

volume will be changed but without 10uf cap there will be minimum gain