Not much free time these days so updates have been slow.. but I have a lot of interesting stuff cooking in the back burner.
One of them is an audio grade RPi.
Essentially it will be a Compute Module 3 on a mainboard loaded with ultra low noise linear power supplies and some necessary peripherals.
The idea came to me quite some time ago but it wasn’t until last November that I decided to actually go ahead with it.
The proof-of-concept PCBs for the mainboard were done by December.
It appears that even the PoC board, with average quality power supplies, has a cleaner I2S output compared to a standard RPi3 powered by an equivalent linear power supply:
RPi 3:
Audio grade Pi:
The next part was the PoC board for the USB Hub & Ethernet controller. That took a bit more time and a 4-layer PCB with numerous 0402 sized components but it too ended up just fine (with the exception of a bad RJ45 footprint..).
So now I have a fully functioning set of boards with average quality power supplies that already performs better than my Squeezebox Touch as a USB transport.
Next step is to design a single board integrating all of the components plus ultra high quality power supplies.
That will probably be a summer project..
I did not even know such pi3 module exists.
Can’t wait to see your result!
How is the project going? Congrats for such a great blog!
Thank you Guilherme for your kind words.
This project hasn’t really taken off the ground yet.. I have been extremely busy with work these past few months so pretty much every project has been on hold..
Plus the new RPi 4 has effectively thrown a spanner in my plans.. If it turns out being better at SQ compared to the RPi 3 I will probably wait for a new version of the Compute Module to come out so as to base the Audio Grade Pi on that.