Dude
Active Member
- Joined
- Dec 10, 2025
- Messages
- 84
Uncompressed, CD-quality stereo audio (16-bit/44.1 kHz) requires exactly 1411 kbps of data: 16 bits × 44,100 Hz × 2 channels = 1411.2 kbps.
WiiM Pro Plus reports the incoming network payload. AirPlay compresses the 1411 kbps audio into an ALAC format for Wi-Fi transmission, which typically shrinks the file size down to around 900 kbps while in transit.
Other devices (or the DAC receiving its optical signal) report the decoded output. It has already received the ~900 kbps ALAC stream, unpacked it, and restored it to the raw, uncompressed 1411 kbps PCM format right before sending it to the analog outputs.
Both devices are processing the exact same lossless 16-bit/44.1 kHz audio. WiiM is showing the compressed size during transit (meaningless); Others are showing the uncompressed size after decoding (at least a little useful).
WiiM Pro Plus reports the incoming network payload. AirPlay compresses the 1411 kbps audio into an ALAC format for Wi-Fi transmission, which typically shrinks the file size down to around 900 kbps while in transit.
Other devices (or the DAC receiving its optical signal) report the decoded output. It has already received the ~900 kbps ALAC stream, unpacked it, and restored it to the raw, uncompressed 1411 kbps PCM format right before sending it to the analog outputs.
Both devices are processing the exact same lossless 16-bit/44.1 kHz audio. WiiM is showing the compressed size during transit (meaningless); Others are showing the uncompressed size after decoding (at least a little useful).