Simple yet powerful audio amplifier
Introducing Simple Amp!
This simple yet powerful audio amplifier is an ideal DIY electronics project. Using a minimum of four parts you can build an amplifier that will put commercial sound systems to shame. Not only is this amp powerful, but it is compact, able to fit in an Altoids tin with room to spare! Check out these instructions on how to build your own.
This is the same amplifier circuit that is used to power the large 8 ohm speaker in Salvius's head. It was very important for this project to have a speaker capable of being heard across a room with clarity. Salvius is designed to be able to interact with people and the quality of sound for the robot's speech plays an important role in the ability to do so.
Nice instruction! I intend to recreate this.
ReplyDeleteOne note: on page 4 after the title page, you say "About the LM683". I didnt notice until later in the show that they were 386's
Thanks and good catch. That was a typo and it has been corrected.
ReplyDeleteWould it be possible to get a picture of the bottom of the completed board???
ReplyDeleteGreat Project...
Thank You
Hi Michale, here is a picture of bottom of the board. I've positioned it such the at side with the battery connection is facing upward. Let me know if you need any more information.
ReplyDeleteI tried to build this as well, but getting some feedback and noise. Either my connections are bad or my speaker is. I purchased a speaker from digikey
ReplyDeletePart # 102-1551-ND
Description: SPEAKER 8OHMS .5W 40MM 6" LEADS
Did I miss read something?
Hi Eric, it looks like the voltage requirement for your speaker is lower than the one I used. This isn't a problem, you just need to add a resistor between the battery and the circuit board. I believe that a 400K ohm resistor might be just what you need.
ReplyDeleteWOW, Thanks for getting back to me so fast. I just went on-line to digikey and a 400k ohm resistor is a little over $3 and a 1.5W speaker is $4. I would rather spend the money on a speaker than a resistor. is a 1.5W speaker big enough? If not than I will go the resistor route, but for the future what are the specs of the speaker?. Again thanks for the help. Much appreciated.
ReplyDeleteI'm using an 8 ohm, 2 watt speaker. The slightly lower wattage shouldn't make a difference because I have used this amp with much smaller speakers than that. You may want to consider getting a potentiometer so you can adjust the voltage input to exactly what you need (http://www.adafruit.com/products/562). Also, what kind of audio device are you plugging this into? Try lowering the volume on the whatever device it is and see if that helps. Assuming that the circuit is working correctly, the white noise you are getting is due to a higher amount of input than it is expecting. This circuit can handle a broad range of speakers, but it requires very little voltage for input.
ReplyDeleteThis is awesome. Would it work to double the ICs and capacitors to create a second circuit and thus a stereo amplifier?
ReplyDelete@Jeff that would work as long as you have a audio source that provides stereo output.
ReplyDeleteI built this circuit but I'm getting an abnormal amount of distortion. Please help!
ReplyDeleteHi Brian, you may want to try reducing the input voltage form the battery. Distortions can sometimes be caused if the input voltage is overloading the gates in the IC's. Try adding a resistor or two between the battery and the board and see if that helps, you will probably have to try a few to get the voltage just right.
ReplyDeleteHope this helps.