Relationship between loudness (volume level??) and Sound Quality

[johnb]

Old Techie,

iPlayer radio has been 320 kbps AAC-LC for many years now.

There is a table at https://www.astra2sat.com/radio/uk-d...adio-bitrates/ which seems recent but does have caveats.
I think Freeview and Freesat are both 192kbps MPEG1 LayerII encoding. That is then packaged into an mp2 transport stream. Converting the mp2 stream to mp3 format should be just a matter of repackaging the MPEG1 encoded audio in a different way

You obviously know much more than I do but are you really sure that converting mp2 to mp3 is just a matter of repackaging? I thought the encoding used in mp2 and mp3 was different.

(I listen to the iPlayer DASH stream via LMS/Squeezebox Touch.)

[Anastasius]

Gosh...all this talk of loudness takes me back decades when I was 'into' hi-fi and electronics. Frustrated with the compression on Radio 3 broadcasts for a while I played around with a four track tape recorder and an expander. Tracks 1 and 2 were the recorded stereo, track 3 was where I laid down a control for the home-made expander to re-establish dynamic range. Results were, for the most part, excellent but the process was terribly time-consuming

[cmr_for3]

Thanks all for the replies

Here is the link to the details of a file https://www.dropbox.com/s/fg2k7okzkg...20TTN.txt?dl=0

[johnb]

cmr_for3,

Thanks for the link.

As you will have noted, the purported "mp3" file is actually an "m2ts" file containing mp2 (aka MPEG-1 Layer2) audio, but given an ".mp3" filetype.

It seems to be just a decrypted copy of the ".ts" file on the Humax hard drive, but given a ".mp3" filetype.

This seems a very unhelpful (i.e. a bewilderingly crazy) thing for Humax to do.

[cmr_for3]

cmr_for3,

Thanks for the link.

As you will have noted, the purported "mp3" file is actually an "m2ts" file containing mp2 (aka MPEG-1 Layer2) audio, but given an ".mp3" filetype.

It seems to be just a decrypted copy of the ".ts" file on the Humax hard drive, but given a ".mp3" filetype.

This seems a very unhelpful (i.e. a bewilderingly crazy) thing for Humax to do.

Indeed, and no matter what I do, I can't get any app to recognize it as a TS file...

[johnb]

Indeed, and no matter what I do, I can't get any app to recognize it as a TS file...

Yes the "mp3" <cough> needs to be demuxed to extract the mp2 audio (which is what you are doing with Xrecode 3, in effect).

Xrecode 3 certainly seems a convenient package.

If I was regularly extracting the mp2 from Humax pseudo ".mp3" files I would probably put a simple batch file on my Windows Desktop. I could then drag the pseudo mp3 files from Windows Explorer to the Windows Desktop batchfile which would then automatically extract the mp2 using ffmpeg (a recompiled version of which XRecode 3 also uses). If you are interested in something like that I could easily post the contents of such a batch file.

[cmr_for3]

If you could that would certainly be useful and appreciated. Xrecode is very useful, it cost me I think about £12 but has been worth it's weight in gold with batch conversations.

[johnb]

cmr_for3,

This works on Windows 7 but I have no experience of W10. (I've been holding off moving to it.)

This looks more complicated than it actually is.

There are two things you need:

- ffmpeg.exe
This can be downloaded via the official ffmpeg website: https://www.ffmpeg.org/download.html
Click on Windows "builds", then select the Release Build (4.1) (not the "nightly" build), select either the 64bit or 32bit build and then select "Static".

The downloaded file doesn't need to be installed - just unzipped.

The ffmpeg.exe (in the bin folder) can be copied somewhere more convenient if you prefer


- the batch file

set FileIn=%~1
set FileOut=%~n1

"C:\folder1\folder2\ffmpeg.exe" -i "%FileIn%" -vn -acodec copy "%FileOut%.mp2"

pause

Where "C:\folder1\folder2\ffmpeg.exe" is the path to ffmpeg.exe on your system (enclosed in double quotes).

Copy the above to Notepad.

Amend "C:\folder1\folder2\ffmpeg.exe" to where ffmpeg.exe is located on your PC. The easiest way to get the path is to use Windows Explorer. Go to where ffmpeg.exe is located. Hold down "shift" and right click on the ffmpeg.exe file - then select "Copy as Path". Check that the whole path is enclosed in double quotes.

Save to your Desktop with a filetype of ".bat", say, "Extract mp2.bat". It MUST have a filetype of ".bat". In W7 the Desktop is C:\Users\<username>\Desktop.

This should then appear on the Desktop.

To use:

Open Windows Explorer so that you can also see the batch file on your Desktop. Find the Humax pseudo mp3 file in Windows Explorer.

Left click on it, holding down the button, and use the mouse to drag it on top of the new batch file icon - then release the mouse button.

The mp2 file will be created in the same folder as the Humax pseudo mp3 file, with the same filename (but with filetype .mp2).

The Humax pseudo mp3 file can have any filetype (ts, mp3, etc).

Final note:

If you want to edit the batch file: right click and select "Edit" (NOT Open). Opening the file will run the batch file without any parameters and it will just show an error message.

[cmr_for3]

cmr_for3,

This works on Windows 7 but I have no experience of W10. (I've been holding off moving to it.)

This looks more complicated than it actually is.

There are two things you need:

- ffmpeg.exe
This can be downloaded via the official ffmpeg website: https://www.ffmpeg.org/download.html
Click on Windows "builds", then select the Release Build (4.1) (not the "nightly" build), select either the 64bit or 32bit build and then select "Static".

The downloaded file doesn't need to be installed - just unzipped.

The ffmpeg.exe (in the bin folder) can be copied somewhere more convenient if you prefer


- the batch file

set FileIn=%~1
set FileOut=%~n1

"C:\folder1\folder2\ffmpeg.exe" -i "%FileIn%" -vn -acodec copy "%FileOut%.mp2"

pause

Where "C:\folder1\folder2\ffmpeg.exe" is the path to ffmpeg.exe on your system (enclosed in double quotes).

Copy the above to Notepad.

Amend "C:\folder1\folder2\ffmpeg.exe" to where ffmpeg.exe is located on your PC. The easiest way to get the path is to use Windows Explorer. Go to where ffmpeg.exe is located. Hold down "shift" and right click on the ffmpeg.exe file - then select "Copy as Path". Check that the whole path is enclosed in double quotes.

Save to your Desktop with a filetype of ".bat", say, "Extract mp2.bat". It MUST have a filetype of ".bat". In W7 the Desktop is C:\Users\<username>\Desktop.

This should then appear on the Desktop.

To use:

Open Windows Explorer so that you can also see the batch file on your Desktop. Find the Humax pseudo mp3 file in Windows Explorer.

Left click on it, holding down the button, and use the mouse to drag it on top of the new batch file icon - then release the mouse button.

The mp2 file will be created in the same folder as the Humax pseudo mp3 file, with the same filename (but with filetype .mp2).

The Humax pseudo mp3 file can have any filetype (ts, mp3, etc).

Final note:

If you want to edit the batch file: right click and select "Edit" (NOT Open). Opening the file will run the batch file without any parameters and it will just show an error message.

Jon

Thats great worked first time - many thanks, much appreciated.

[Beresford]

...

Personally, I use the one remaining Shoutcast (ICY) stream in the system for Radio 3. This is the same AAC encoding used for Sounds/iPlayer but can be played by foobar2000 by opening the pls stream. Foobar2000 can use output methods that bypass the Windows mixer reprocessing of the audio...

I too use this method on a Windows PC. But I haven't found a way to make audio from Listen Again (Sounds) bypass the Windows mixer. Do you know if it can be done?

[cmr_for3]

Hello

I may be able to advise as I have been experimenting with this. I've gone back to winamp as it has had a new release. Having got a new set of speakers I wanted to make full use of them. whilst researching output plugins for winamp I become aware of a technology in Windows called wasapi which is supposed to bypass the Windows mixer. It does sound clearer to me. Having no really got on with foobar I'm not aware of it's plugins but a google suggests they do exist... https://www.google.com/search?client...+plugin+foobar

[Bryn]

With the browserless QOBUZ app, you can even select wasapi exclusive, blocking all audio except that from QOBUZ.

[Beresford]

Hello

I may be able to advise as I have been experimenting with this. I've gone back to winamp as it has had a new release. Having got a new set of speakers I wanted to make full use of them. whilst researching output plugins for winamp I become aware of a technology in Windows called wasapi which is supposed to bypass the Windows mixer. It does sound clearer to me. Having no really got on with foobar I'm not aware of it's plugins but a google suggests they do exist... https://www.google.com/search?client...+plugin+foobar

Yes, for live listening, for better quality than my Freeview, I use the Kernel Streaming plugin, which bypasses even more of Windows innards than wasapi, (windows audio something application programmers interface?). Also I sometimes set Foobar output to have exclusive use of the audio device driver.
But the issue is that I can't use it on SOUNDS (Listen Again) because all the browsers send all audio to the Windows Mixer, as far as I know.

[cmr_for3]

Yes, for live listening, for better quality than my Freeview, I use the Kernel Streaming plugin, which bypasses even more of Windows innards than wasapi, (windows audio something application programmers interface?). Also I sometimes set Foobar output to have exclusive use of the audio device driver.
But the issue is that I can't use it on SOUNDS (Listen Again) because all the browsers send all audio to the Windows Mixer, as far as I know.

This might be of use. https://www.head-fi.org/threads/chro...-audio.747478/

[Beresford]

Chrome wasapi

This might be of use. https://www.head-fi.org/threads/chro...-audio.747478/

Thanks. I will try this out when I install Chrome on Windows 10.