File Specifications - Newbie Question

Total novice to all this, but here goes.

Been asked to record in an audio file speck MP3@256kbps, 48khz, Mono Track, Broadcast Complaint.

One can assume that Audacity meets all these requirements…if not, what if any adjustments do I need to make.

I also noted in the past that I had difficulty converting from a WAV file to MP3 and tips would be welcomed.

Thanks in advance for your help

I had difficulty converting from a WAV file to MP3

Audacity doesn’t naturally have the ability to create MP3 files, so the Lame encoding software must be added.

MP3@256kbps, 48khz, Mono Track, Broadcast Complaint.

We got the rest of that, what does “Broadcast Compliant” mean? Or better still, “Broadcast Complaint.” Is that the response you get if you fail to reach compliance?


48KHz is the sampling rate associated with video. 44100 is associated with Audio CD.

Audacity > Edit > Preferences > Quality > Default Sample Rate: 48000 > OK.

Sometimes stereo/mono is determined by the interface or microphone and you don’t have a lot to say about it. If you have an actual stereo show, two blue waves with different show on each one, Tracks > Mix Stereo down to Mono.

If you have “fake” stereo or two identical blue waves (watch for differences in the bouncing sound meters), you can mix down as above, or use the drop-down track menu on the left > Split Stereo to Mono > [X] delete one of the two tracks.

So that’s it. Next is you tell us what Broadcast Compliant is.

ACX AudioBook publishes clear documents of the submission they expect. Audio peaks not to exceed -3dB, etc. If the broadcast requirement is close, we may be able to use the same mastering tools.


For the MP3, [u]download install the LAME MP3 encoder[/u] if you have not already done so.

Then file → Export → Export as MP3.
Save as type: MP3 Files
Bit Rate Mode: Constant
Quality: 256 kbps
Channel Mode: Force export to mono

Convert to MP3 ONCE as the LAST STEP. Do all of your editing & production as WAV (or as an Audacity Project). Although MP3 can often sound identical to the original, MP3 is lossy compression. It gets decompressed when you open it in Audacity and if you re-export to MP3 that’s another generation of lossy compression, and the “damage” does accumulate.

“Broadcast quality” probably relates to the overall production “sound quality”, not the file format details. i.e. It should sound like it was professionally performed and recorded with very-low background noise, and it might need a specific “loudness”, etc.