Hello,
I am trying to create a Arduino project which will read a sound file from a SD card. Till now, for testing purposes I used a small speaker (I have no clue what its specs was, it worked fine). I have now got a bigger speaker (10w, 4ohms). When I connected it directly to the Arduino UNO R3 board, while uploading, I got an error:
Sketch uses 12016 bytes (37%) of program storage space. Maximum is 32256 bytes.
Global variables use 1046 bytes (51%) of dynamic memory, leaving 1002 bytes for local variables. Maximum is 2048 bytes.
An error occurred while uploading the sketch
avrdude: ser_open(): can't open device "\\.\COM3": The system cannot find the file specified.
Just in the morning, I used this UNO R3 with something else, and that worked perfectly fine, So I decided to check about the speaker. I realized it needed an amplifier with the Arduino UNO R3 board, but I'm not sure, which one should I use...
Any speaker amplifier will work. The speaker rating just tells you the maximum possible power input to the speaker.
If you really want the full 10 W output that the speaker can produce, while blasting people's ears, then choose an amplifier capable of producing at least 10 W output.
This gives the impression that you do not need that much power:
You probably don't need 10W, and you'd need more than 5V if you want to get 10W.
You can get a complete amplifier, or regular "powered" computer speakers will work. Or, you can get an amplifier board or you can get an amplifier chip and build your own circuit. Just make sure to get a "power amplifier" chip. (An op-amp can't drive a speaker.) The LM386 is a popular easy-to-use chip. It puts-out less than 1 Watt. Or there are tons of other amplifier chips.
