Over the phone network, ARC is lossy [resolved, lots of good suggestions here]

The idea of delivering the whole metadata to devices, which are not on the local net is very good. The ARC interface looks good and is functional.

UAPP is also an all sources in one app solution (including also Internet Radio). Yet it is less well integrated and does not offer all those metadata. It has the advantage that its control on the output allows for a finer control of the volume. The volume steps in Android audio are just too big, a default it transmits to ARC.

My biggest surprise was to discover that on the go (phone data), the data transmitted are lossy. Streaming from Qobuz, I get some mp3, without any information on the bitrate. Streaming from my CD collection (FLAC), the data are encoded to 256 kb/s. The codec used is from Opus, certainly excellent, the data are nevertheless compressed.

Using the Qobuz app in the same setting, I get full CD quality. With Qobuz over UAPP I get the same result (824 kb/s in the tested case, which is very good FLAC).

Even compressed, the sound quallity is quite good. I did note make direct comparisons; my ears are old and I did listen with IEMs in in public transmport. Nevertheless, I think that roon should not just blow the tromps about the great novelty, they should also announce the limitations and explain their choices. Shall we need 5G or… 6G to get the full data? Are there some other criteria? If they fail to do that, their big progress risks to come out as… somewhat fake.

Reto

In ARC Go to setttings and turn off Automatically pick best quality.

You can then choose what settings you want.

Arc just picks lossless for WiFi and lossy for cellular.

I get lossless high resolution by setting both WIFI and cellular on “Original Format” in Roon ARC and attaching a capable DAC to my iPhone.

It will be lossy of course just like all other streaming services if your internet is poor it will change the bit rate on the fly to cope

Right, it’s not the most intuitive way to modify that, but you can turn off the ‘Automatically pick the best quality’ setting and then you can specifically pick CD quality for when using data to make that better. No lossy for me!

I think “Best Quality” means best quality for the situation. Some people don’t want to use a lot of data over cellular. People should really spend a little time exploring their apps to understand how they work. The Roon ARC app is very simple with only a few settings.

Thank you all, I made the recommended changes.