[PROBLEM] Adding Radio station stream very quiet.

[Relocated2007]

I want to add a Radio stream from the station Open FM :

Code:

https://stream.open.fm/33?type=.aac

In the web browser, it is playing quite loud but when I add via a plus button in moOde it is very quiet. How can I set it up to be louder? Apart of pump up volume to max which is still too quiet in my opinion.

[the_bertrum]

Just tried that on my player, and yes it is very quiet indeed. I could get it a little louder by removing the ?type parameter, but I'm not knowledgabe enough to hazard a guess as to what it is in the stream that makes it so quiet.

[TheOldPresbyope]

There's a lot of Open FM stations. I chose two others at random (https://stream.open.fm/3 and https://stream.open.fm/79) and they also played very softly compared to, say, FluxFM stations.

I notice a very short, louder burst each time I switch to one of the Open FM stations after which the station continues playing softly. This might be due to something else but I wonder if it indicates some in-band communication of gain adjustment? FYI, I'm using default MPD settings so ReplayGain and VolumeNormalization are off.

I can spell "ALSA" but I don't claim any real knowledge of what goes on inside it (ETA- not to mention the stream decoders in MPD) so I'll step back now.

Regards,
Kent

[Tim Curtis]

The broadcaster is prolly using an odd format that isn't compatible with the particular codec MPD is using to decode the stream.

The vast majority (99.9%) of broadcasters use either MP3 or plain AAC but some for example BBC use AAC-LC. There are also a handful of broadcasters that use FLAC.

[TheOldPresbyope]

Ah, could be. The response from the server says it's aacPlus (aacp) as seen here in what I captured using wget

Code:

--2022-04-05 11:00:58--  https://stream.open.fm/33
Resolving stream.open.fm (stream.open.fm)... 193.222.135.71
Connecting to stream.open.fm (stream.open.fm)|193.222.135.71|:443... connected.
HTTP request sent, awaiting response... 
  HTTP/1.1 200 OK
  Content-Type: audio/aacp
  Date: Tue, 05 Apr 2022 15:00:58 GMT
  icy-br:48
  ice-audio-info: bitrate=48
  icy-br:48
  icy-description:Grupa Wirtualna Polska
  icy-genre:Misc
  icy-name:33
  icy-pub:1
  icy-url:http://grupawp.pl
  Server: Icecast 2.4.0-kh4
  Cache-Control: no-cache, no-store
  Access-Control-Allow-Origin: *
  Access-Control-Allow-Headers: Origin, Accept, X-Requested-With, Content-Type
  Access-Control-Allow-Methods: GET, OPTIONS, HEAD
  Connection: Close
  Expires: Mon, 26 Jul 1997 05:00:00 GMT
Length: unspecified [audio/aacp]

Apparently, aacPlus is also known as high efficiency (HE) aac. Neither name is mentioned in the MPD documtation of decoder plugins.

Regards,
Kent

[Tim Curtis]

They must be streaming at a really low bitrate (quality) to be using that codec. Maybe something like 32K. It's rare to see any broadcasters streaming at < 64K AAC or 128K MP3. The only station in the moOde collection is Buddha Radio at 32K MP3 and yes the SQ is bad. I don't know why it's still in the moOde collection.

[Relocated2007]

Hi Guys,

Thanks for some inside, it is low bitrate indeed when is ACC is it 42kbps or going down to 37 even sometimes.

However, I make a bit of adventure and put some guessing to work I made:

https://stream.open.fm/33?type=.aac to https://stream.open.fm/33?type=.flac .... and it is still playing! A bit louder too.

Mode is doing a great job making this sounds not too bad, and my ROTEL is making this even nice to hear as the background music which was my intention so risk pays off.

I am now just thinking if for my FLAC rips is worth buying DAC or just stick to USB on pi and DAC in Rotel (which is not great but I like the sound) So probably do not fix it which is not broken ;-).