I just received two SparkFun Mono Audio Amp Breakout - TPA2005D1(part number 11044, https://www.sparkfun.com/products/11044) and I’m having an issue when I hook it up. Actually two issues. The first is that one of the two units I bought doesn’t seem to work. When I hook up power and ground (5 V) the whole unit gets quite hot. I added 2 100k ohm resistors to boost the gain as outlined in your quick start guide (https://www.sparkfun.com/tutorials/392), so I have a feeling it was my fault and I shorted something out. I took out the resistors and it still persisted.
The second issue I’m having is with the sound quality. I salvaged the two speakers from an old iHome radio adapter thingy (https://www.ihomeaudio.com/iP9BRC/). I’m not sure if it’s the exact one in that link. The unit was quite old. Anyways, when I was setting the amp and speaker up, I used a left/right YouTube video (https://www.youtube.com/watch?v=hTvJoYnpeRQ) that just alternates between the left and right speakers by saying “left channel, right channel…”. That spoken word sounded just fine, but when I load up anything else, especially people speaking, but really anything. It sounds terrible: tinny, but also somehow base heavy, and somehow it’s much quieter than the left/right tester.
Any suggestions? This is my first time using an audio amp of any sort in one of my projects. Thanks!
Can you provide some photos showing the tops and bottoms of each amp board and a photo showing how you have everything connected too them? If the board got hot, it’s possible you shorted something out and it may have been damaged. Does the other one not get hot and work OK?
Sound quality issues could be a few different things.
- You could have too much gain
- Your audio input might be at too high a level
- The speakers you are using might be too small for the amp.
- Other issues. (The first 3 are the most likely)
I’m not able to tell you which of those it is, you’d need to experiment to figure it out. I’d start with the stock gain and slowly increase the audio input level to test with.
I’ve attached a picture of my wiring setup and the front and backs of the boards. I removed the resistors I had added to boost the gain and tested the setup at default gain with 4 different speakers, ranging from the 2" diameter I originally tried out, up to some like 6" or 7" diameter ones from my old stereo. The all presented the same problem. The sound source is coming from the audio jack of my computer (a Chromebook) and its volume setting doesn’t affect anything. Other than raising or lowering the volume, of course. I also hooked it up to a LCD monitor control board, which is what this project is for, and still the same issue.
Any suggestions what my next steps should be? Thanks
It’s quite possible you lifted a trace when soldering to the non working board and you’re going to need to replace that one. If you purchased the board from the SparkFun website, fill in the [form on this page with your order number, the part number and the URL to this forum post and we will see what we can do for you.
One other thing that could be causing you issues:
I see headers through the power and input pads on your board to connect it to your breadboard but those headers are not soldered in place. This is another thing that could be causing your low quality audio issues. Solder the headers in place and then plug the board into the breadboard and see if that helps.](Return Policy - SparkFun Electronics)
Whelp I figured it out. I hadn’t connected the ground wire for the speakers. I had been connecting both positive line for the stereo output to both inputs of one speaker. I feel silly, but thanks for your help!
