a)
Yamaha YVC-200 - is a conference speaker
PHONE - it's heavily DSP optimized to work on the desk and to enhance human voice clarity. It isn't meant to work as a full-range audio fac.
what you really need is a DAC hat for your pi, DAC2 HD from HiFiBerry is a very popular choice and measures very well:
A blog for audiophiles about more objective topics. Measurements of audio gear. Reasonable, realistic, no snakeoil assessment of sound, and equipment.
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