Hello, fellows. First of all, I must say that I’m not a Linux guy. Also, I know very little on electronics. I am in fact a biologist with some degree of soldering skills. I can, of course, follow recipes and this is what I did.
Sometime a go, I discovered that I could use a very simple computer, a RPi, to fuel my DAC/amp combo with files stored in a NAS. Cool! So I bougth a RPi 2 B and managed to get it working (not without some pain) with my Modi/Magni combo. The result was so interesting that I decided to build another Volumio box, this time to feed a microsystem. For this one I bougth a RPi A+ with an USB wi-fi dongle and no DAC for start. It worked, but I was annoyed for the lack of a DAC. Due to the actual Brazilian customs and cambial scenario, I decided not to buy a DAC, but build a very simple one. I choose the TI TDA1543A due to the very few accessory components needed to get it running. I scavenged another DAC schematics for a power source and built the TDA1543A DAC in a protoboard. When I plugged it in the i2s output of the RPi, I got no sound. After poking a little in the Volumio via SSH and WebUI, I finally got some noise, with the music faintly heard in the background . In the process, I have edited the /etc/modules, /etc/modprobe.d, /etc/raspi-blacklist.conf and /etc/asound.conf. As the system is today, with the i2s Hifiberry and sndrpihifiberry output selected, when I type asound -l, the system answers that isn’t any soundcards connected.
As an attempt to determine if the DAC was truly working, I plugged it in an old Philips CD player that helpfully used the same DAC chip and it worked flawlessly.
Obviously I have done something wrong in the process. My hunch is that is something in the Linux configuration, but I am too green to find the error.
Here some photos from the DAC.
Raspberry Pi A+, wi-fi dongle and microSD card.
DAC in protoboard. In this picture there is a wrong connection. The output caps are connected directly in the 1Ks resistors. The resistors must bleed to ground and the caps must be connected to the pins 6 and 8 of the TDA1543A. This mistake was corrected.
Using the CD player as transport to feed the DAC.
DAC connected to RPi. Just noise.
Can someone help me to debug this thing?