MEASUREMENTS: JustBoom Digi S/PDIF HAT for Raspberry Pi. (Plus "Why isn’t digital audio 'just ones and zeroes'?" anxiety...)

I mentioned a few months back in September that I updated my Raspberry Pi 3 B+ Touch device with the JustBoom Digi HAT for S/PDIF coaxial and TosLink digital audio output. Over the last few months, I've been using it more regularly for my nightly music listening.

As I noted previously, this device is essentially a 1-chip solution featuring the Cirrus/Wolfson WM8804 transceiver with jitter attenuating PLL (rated intrinsic jitter of ~50ps RMS) released in 2009. It also uses the Murata DA101JC isolation transformer for the coaxial output.

The device is rather plain otherwise as you can see. It does sound good and is capable of up to 24/192 with both coaxial and TosLink outputs. And at <US$40, it's also very affordable. Let's see how well it measures!

Update: Raspberry Pi 3 B+ "Touch" Streamer, JustBoom Digi HAT, 3.0A power supply... And did they mess up Coltrane's "Both Directions At Once" in hi-res!?

Back in early 2017, I documented on the building of my little Pi "Touch" music streamer that I've been using over the last while for playback through my Logitech Media Server system at home. Over the last year, I've used this quite a bit for music playback and also some of the testing I've done on this blog.

As some of you may know, there has been an update of the Raspberry Pi 3 to the B+ model (~US$40). The upgrade isn't a major change to the existing Pi 3 board. However the new SOC, based on the Broadcom BCM2837B0 quad-core Cortex A53 (ARMv8, 64-bits) is slightly faster at 1.4GHz (1.2GHz previously, about 15-20% speed gain), and another upgrade is better ethernet speed which supports gigabit link but since it's still communicating through the USB2.0 port, will max out at ~300Mbps. In some benchmarks I've seen, though not true gigabit speed, the throughput is about 2x that of the previous Pi 3. For those interested in wireless connectivity, there are upgrades in the WiFi and Bluetooth departments as well.