Boss is/was the most successful Dac made for RPI. The combination of great sound and great value proved very successful.

For sound quality we decided to use the new Cirrus Logic DAC CS43198 as a master (another first from the ALLO team). Unlike pcm5122, it has excellent THD (-120 vs – 83). Unlike Ess, the sound is “darker” (not bright, low out of band noise).

We are using over 30LDOs (as usual), two super caps and countless filters. We also upgraded the power input filtering with common mode chokes.

We recommend Nirvana (with earthed switch on) for best sound quality (measurements) but even a cheap PSU will degrade the THD by 1 to 2db.

Boss2 is a meaningful upgrade over Boss in sound quality (measurements, THD / Jtest) and a much better "bang for your buck".

While the WIFI of RPI4 is better than previous models, it is still not great. We highly recommend adding our WIFI dongles (or use your own). In our tests, RPI4 + Boss2 with acrylic can reliably play hi resolution files with a standard WIFI access point no more than 9 to 10m away. Boss2 and RPI4 with ALU case plays reliably at around 5m or less. Using WIFI dongles will increase the range substantially (we are able to reach even 20m through one wall).

Features:

Boss2 Acrylic Includes: Boss2, Acrylic Case with OLED screen and Remote control. Case compatible with RPi4 only.

Power Input 5V 2.85 Amp:

Via Boss2: Jack Barrel 5.5 X 2.1 mm. Compatible PSUs: Shanti, Nirvana and regular 5V PSU.
Via RPi4: Type-C USB input. Shanti PSU, Nirvana SMPS and our 5V PSU includes 1 X Type-C adapter.
Please note if you feed 2x PSU, Boss2 needs only 100mA.

Note: Type-C adapter cable sold separately.

Documents: