Page 101 - Raspberry Pi as a Foundation for Boosting Computer and Technology Literacy

Advanced RPi-based DAC 8.2

Figure 8.4
Advanced Raspberry
Pi-based DAC

To make a long story short, let us just say that every phone, tab-
let, laptop, or personal computer has a DAC soldered to its mother-
board, including Raspberry Pi (except Pi Zero and Pi Zero W). One can
connect headphones directly to the Raspberry Pi headphone output
and listen to music. One will soon discover that this is not the best
way to enjoy ‘It Never Entered My Mind’ by Ben Webster and Cole-
man Hawkins ripped and stored on the NAS you have just made with
a Raspberry Pi 4. The Raspberry Pi is a general-purpose computer and
introduced so much electrical noise that it made listening unbearable.
The playback also deteriorated due to poor clock accuracy because the
clock on Raspberry Pi has not been optimized for this purpose. The
third source of sound deterioration was the poor-quality power supply,
which is not suitable for music reproduction. For serious music repro-
duction in a hi-fi system, dedicated high-quality audio components are
preferred. Here, there are two options: one can buy a standalone DAC
(start with Schitt Audio, then upgrade by purchasing a Chord Electron-
ics high-quality DAC) or – and this is a much better option, both finan-
cially and experience-wise – build one yourself, using a Raspberry Pi 4
with 4 or 8 GB RAM.
A glimpse at Figure 8.4 will give an idea of the final product of your
building efforts. Raspberry Pi 4, the heart of the build, is in the up-
per left corner, sitting upside down and next to the smaller green PCB

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