Digital Output from a Chromecast Audio Streamer?

To Doug Schneider,

Thanks for reviewing the Heaven 11 Billie integrated amplifier-DAC.

I have a question regarding your setup. What is the “partnering TosLink interconnect” you refer to in this sentence, and how are you using it with the Google Chromecast Audio streamer? You wrote: “I connected a Chromecast Audio wireless streamer ($35, discontinued), using its partnering TosLink interconnect ($10, discontinued), to one of the Billie’s TosLink inputs, so I could wirelessly stream uncompressed music from Tidal.”

I have a Chromecast Audio but only ever used its 3.5mm output jack to connect to the RCA input of my AV receiver. So, I am wondering how it can be used with TosLink.

I’d like to ask one more question. When I play Tidal over Bluetooth it uses the Masters setting, but I assume the quality is ultimately lowered due to the limitations of Bluetooth transmission (even with aptX). However, when I use Tidal over Chromecast Audio it reverts to HiFi quality, as you mention in your answer to Kiran’s question. So my question is whether Bluetooth or Chromecast Audio offer better quality from Tidal. I suppose the Masters setting on Tidal via Bluetooth is misleading since it gets compressed later on?

Thanks,
Alexander
Switzerland

Great questions!

What many people don’t realize is that the little Chromecast Audio jack outputs a digital or analog signal, depending on the type of cable you connect to it. Currently, you are connecting your Chromecast Audio to your receiver with an analog cable that has a 3.5mm connector on the Chromecast side and RCA connectors on the receiver side. When connected with an analog cable, the Chromecast uses its built-in digital-to-analog converter (DAC) to output an analog audio signal.

If you purchase what’s called a mini-TosLink cable—which is a digital optical cable that has a 3.5mm connector on one end and a TosLink connector on the other—and connect that to the Chromecast Audio and the other end to the TosLink input on your receiver (all receivers have them), the Chromecast device will automatically bypass its own DAC and shoot out a digital signal to your receiver via the TosLink cable. This allows your receiver’s DAC to convert the signal from digital to analog. Depending mostly on the quality of the DAC in your receiver, this may be a better way to connect your Chromecast Audio.

When Tidal outputs in HiFi mode, the resulting files are streamed at 16-bit/44.1kHz resolutions. Tidal’s Masters setting outputs the proprietary MQA format, which, using a lossy compression algorithm, can pack high-resolution music files (e.g., 24/96 and 24/192) into 24/44.1 or 24/48 files. When you stream wirelessly with Bluetooth, the bitrate, regardless of the flavor of Bluetooth codec used, is lower than 16/44.1, so any file listened to that way will be at a lower resolution. The Chromecast Audio can support resolutions up to 24/96, but, unfortunately, Tidal’s software won’t stream higher than the HiFi setting (i.e., 16/44.1) to it—that’s why, even if you select Masters, Tidal will always revert to HiFi quality when streaming begins. Still, I’ve found that many music selections still sound great at the HiFi setting, so it’s not that much of a deficiency. I hope these answers help. . . . Doug Schneider