I have been running the Kali reclocker / Piano 2.1 combination on RPi 2 for some time.
This represents a fantastic value and great sound quality at very little money.
Running Moode 2.6.
Been doing lots of A/B testing RPi2 / Kali/Piano 2.1 against Desktop PC / Windows7 / JRiver / Asus Xonar Essence STX sound card.
Started the same song on both devices at equal sound level. Using large Genelec monitors.
I am addicted to 96K resampling. Resampling brings out the digital effects and soundscapes
on modern music. So both palyers were running resampling at highest quality.
Some friends could not tell the difference between PC / RPi. They could not believe
that the small, inexpensive RPi could sound this good.
After many tests, I can hear only one difference. The Kali/Piano/RPi/Moode combination
introduces a small amount of soft compression on the sound. This is a matter of
opinion, but I would like it without compression. The PC/Xonar Essence is a bit
more lush and open. The RPi slightly compressed.
I have plans to test Volumio. Also the Volt amplifier with Sparky SBC.
Analogue: Thorens TD 160 Super, Micro Seiki CF1 arm, Toshiba SR-370, Micro Seiki MA-505 arm, Nagaoka MP-50, Ortofon S 15-TE
Source: JRiver 20, RME 9632 sound card, cd Micromega Drive 1, Hegel HD2 dac, Asus Xonar STX
Pre-amp: Quad 33, Audiolabor VV2020
Amps: Quad 522, Quad 405, Nakamichi Amplifier 1, CEC Amp 3300
Speakers: Kef 104/2, ESS Amt 1 Monitor, Magneplanar 2.5/RT, Yamaha NS1000M - Active Genelec, cable Mogami 2513 "Blue Rocket"