You are right in that he did not tweak the Pi4 to get it at it's best. I think the other thing is that digital sound has improved dramatically in the last two decades or so, basically the bar is pretty high now.
David McGown wrote:
Interesting article. I think he is right about the limitation of the Pi4 as a streamer, there are ways to tweak it more than he does (power supply, USB isolator), also digital hats for S/PDIF instead of USB output. There are alot of respected digital streamers that use RPi's or other ARM based SBCs as their CPU. Both the BlueSound and Primare players are likely based on an ARM SBC like the Pi. Computing power is not the limitation, I presently use a 32-bit Intel Atom board in my Roon endpoint that is about the same computing power as a Pi4, which is far better sounding. I think the problem is that the Pi is a general purpose device that is not engineered to address power supply, timing, and noise issues that are important for quality digital playback. Unlike an open bus system like Intel, where it is possible to bypass the compute functions from the digital streaming I/O functions by use of bus mounted and separately powered interface cards (like from SoTM or JCAT), one is stuck with the interfaces on board the computer with the Pi, with the Pi4 being an improvement over the Pi3.
David