re: F* a soundbar, building a DIY sound system - Update pg 4 - paywalls suck

Update:

It took a while for the parts to come in, and then once they did I realized I had made a mistake. The HiFiBerry Amp2 and the Audio Injector are both HATs (Hardware Attached on Top) for the RPi, and since they use the same I/O pins they are not compatible. So I had to order a USB audio adapter with mic port to use instead of the Audio Injector, which came in today. I put the standard Pi OS on the microSD, booted up, edited one config line to get the Amp2 to work, and the USB adapter worked automatically. I used an old speaker I already had for testing, hooked it up and it sounds great. Then with one command I can pipe audio from the mic port straight through the Amp2 and to the speaker. I will launch this command automatically on boot once I've got all the details ironed out, so that all you have to do is supply power and an audio source and I have a working amplifier. It boots up a lot faster than that fricking soundbar I bought, and it won't go to sleep like a dumbass.

One problem is unfortunately my TV's audio output does not adjust volume, so now I need to make the Pi adjust volume itself. I ordered an IR receiver today, as well as a small LCD display. With these I will be able to control the Pi with any infrared remote, and make it execute arbitrary commands in response to arbitrary signals. In my case, I need the TV to still power on/off with the Roku remote, so it has to remain programmed for my TV. I will just record the IR output from the remote for volume up/down and config the Pi to adjust volume based on that. And of course the display panel will indicate the volume level, and I will probably also make it show the input source, and maybe its IP address and whatever else will fit.


I am using a Raspberry Pi 3 Model B, which has wifi and bluetooth, so my options for control and expansion are pretty wide. I can write a simple API with a web UI or mobile app for control. And I will need to do some testing, but I believe I can add speakers with another Pi+Amp attached anywhere in the house and stream the audio to it via wifi, which I guess will make it a DIY Sonos system.


Cost:

RPi3B - $42 (already had)
HiFiBerry Amp2 - $56
18V power supply - $26
USB audio adapter - $5
Display - $7
IR receiver - $1.50
Misc cable & wire - $5
========
Total - $142.50


Once I get it all together with the IR receiver and display, I will design and 3D print a housing. I am also waiting to snipe a price drop on a pair of decent (for me) bookshelf speakers, which are typically $99 but I hope to get for ~$75. So all in I will still be under $250, and I believe it will sound much better than any similarly priced system. It will also be palm-sized (minus the speakers), and hopefully the foundation of a future whole-home audio system. Plus so far it's been a fun project.


If anyone is interested, when it's all done I will post some pics and a guide.