Fortunately, you don't have to listen to internet hearsay, because Arcam typically tell you which DAC IC they used in their AVRs. In this case, whoever told you the Arcam DACS were better, might not have the facts.
Arcam - AVR850(Discontinued) - AV Receiver
PRODUCT DETAILS
- Dolby Atmos & DTS:X 7.1.4 decoding
- 4K (UHD) HDMI2.0a with HDCP2.2
- 7 HDMI inputs, 3 HDMI outputs, ARC compatible
- Dirac Live ® for Arcam room correction
- Spotify ® Connect enabled
- Cirrus CS42528 audiophile DAC
- Class G power amplification
- Ethernet, RS232 and IR control
- Free MusicLife iOS UPnP and control app
CS42528 pdf, CS42528 Description, CS42528 Datasheet, CS42528 view ::: ALLDATASHEET :::
The Oppo 203 uses the AK4458VN:
OPPO Digital - Knowledge Base
Differences Between the UDP-203 and UDP-205 | | |
Features | UDP-203 | UDP-205 |
7.1-Channel Analog Outputs | Yes (AKM AK4458VN DAC) | Yes (ESS ES9038PRO DAC) |
If you compare the specs of the Arcam and Oppo's DAC IC:
Arcam's: 114 dB DR, 100 dB SINAD
Oppo's: 115 dB DR, 110 dB SINAD
I would say based on the specs of the DAC chips, Oppo won by miles (10 dB lower in THD+N).