Live Radio bit rates being misreported?

Every station I click on and interrogate signal path states the stream is 24-bit - I think that would be unlikely

Do you see that on the first entry (Source) in Roon’s signal path?

Typical bit depth reported for radio streams:

  • MP3 16-bit – update: maybe not so true see my post below
  • AAC 24-bit

It might be meaningless in both cases anyway or referring to the uncompressed PCM stream bit depth (after decoding the MP3/AAC stream):

Yes - even on 32kHz 96 kpbs streams 24-bit depth is being reported - that can’t be right surely?

You’ll see 24bit on any mp3 stream in Roon, even if you are playing from a ripped file. Roon chooses to reconstruct the mp3 data at 24bits. See this useful post from one of Roon’s devs.

Nope, Roon is reporting 16-bit for MP3 on my system (QNAP NAS). Example is taken from Radio Paradise: Main Mix.


Update: Maybe server (ffmpeg version) dependent? Roon reports 24-bit for the same stream on my secondary server (CentOS 7).

Weird. I see

Which is what I expect. Core on Rock

I have noticed that when one examines the signal quality panel of live radio stations, most show that the signal is 24 bits in terms of bit depth. This is so even though I have all DSP functions disabled, specifically upsampling/resampling. It is my understanding that most internet radio station broadcasts are natively 16 bits.

Why do Live Radio stations show up as 24 bits when most are only 16 bit transmissions? Is this an error in the signal quality display function for Live Radio or is there some behind-the-scenes resampling taking place?

Certainly the sound of many stations through Roon’s Live Radio function differs from the sound of the same station through, for example, Lumin’s radio function. Lumin’s radio function displays 16 bits as the bit depth for most internet radio stations which, as I understand it, is the native bit depth of most internet radio transmissions. I’m not saying that Roon’s signal is better or worse in sound quality, but it’s hard to deny that the sound quality differs between the Roon and Lumin versions of the same station even when I’m reasonably sure both are playing the same stream from the station.

I find no way to change the bit depth of Roon Live Radio signals from 24 bit to 16 bit. I would like the option to listen to Live Radio signals in their native bit depth which, as I said, to my understanding is usually 16 bits. Could a function be added to allow overriding the resampling of internet radio stations from16 bit to 24 bit?

Thanks for your consideration and response.

Hi @Thomas_W_Mallin,

I’ve moved your post into this existing topic, check it out.

I think the post that was referenced above is quite pertinent… hope it answers your questions…

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