MP3 Decoding Failed Errors

I am using Windows 8.1. I recently recorded records and want to import them into Audacity (current version) to edit the sound quality and cut the beginning and ending times. I am getting continual decoding failed error messages. How do I resolve the Reserved Sample Frequency Value error message. Thanks.

I’m not familiar with that error but how did you create the MP3s? I assume you didn’t use Audacity?

If you can play the files (with whatever player software you normally use) they are probably recoverable so try converting them to WAV with [u]TAudioConverter[/u].



FYI - You should avoid editing MP3 files if possible. MP3 is lossy compression and when you open an MP3 with any “normal” audio editor they get decompressed. If you re-export as MP3 you are going through another generation of lossy compression and the “damage” does accumulate. If you want MP3 you should compress ONCE after all editing is done.

There are some special-purpose programs that can edit MP3 without decoding but they can only do “simple” things like cutting, pasting, and changing the volume. You can’t equalize or do noise reduction or mixing, etc., without decoding first.

Point this analyzer to one of the files and report what it says.

https://mediaarea.net/MediaInfoOnline

Koz

As DVDdoug above, doing original production in MP3 is a terrible idea. MP3 burns in compression distortion, it gets worse as you edit, it’s permanent, and you can’t stop it.

Koz

General
Complete name : Ah Ha Night Club Orchestra.mp3
Format : MPEG Audio
File size : 3.23 MiB
Duration : 3 min 31 s
Overall bit rate mode : Constant
Overall bit rate : 128 kb/s

Audio
Format : MPEG Audio
Format version : Version 1
Format profile : Layer 3
Duration : 3 min 31 s
Bit rate mode : Constant
Bit rate : 128 kb/s
Channel(s) : 2 channels
Sampling rate : 44.1 kHz
Frame rate : 38.281 FPS (1152 SPF)
Compression mode : Lossy
Stream size : 3.23 MiB (100%)

Seems OK. What application made the MP3s?

Will they open and play in Windows Media?

Koz

That information looks OK, but MediaInfo doesn’t find every problem with an MP3. It does conform that you really have an MP3… Sometimes we see other formats named .MP3.

At this point it’s probably better & easier to start-over and re-digitize the records. Then save (export) as WAV until you are finished editing. Then if you want MP3, export to MP3 ONCE as the last step.


You didn’t say if you can play the MP3 with other software.

If TAudioConverter can convert the MP3 to WAV, you can edit the WAV and then export to MP3 again. That’s two generations of lossy compression but it’s no worse than opening the MP3 in Audacity.

There were some recent changes to Audacity and it’s now pickier about MP3 files being “correct”.

[u]MP3 Diags[/u] may be able to repair your MP3, but it’s an “advanced” tool with lots of options so it’s not necessarily easy to use.

If you do start-over - If file size is not a big concern, consider using a higher-bitrate/higher-quality setting when you make the MP3. 128kbps is may be OK, but higher bitrates are normally used for good-quality music. Higher bitrates make bigger files. Less information is thrown away during the lossy compression so they potentially have better sound quality. Also VRB (variable bitrate) or ABR (average bitrate) make more efficient use of the bits than CBR (constant bitrate). And assuming it’s a stereo recording, ‘Joint Stereo’ is better than regular stereo.

The MP3 files were created using a record player that had a recording option. They are 78rpm record recordings.

I downloaded TAudioConverter but do not know how to convert the MP3 files to WAV files.

I am not that tech-savy. The recordings play when I double-click on the files.

I want to trim the start and end times because I had to place the needle on the records and then remove the needle after the song played creating lag times in the front and end of the recordings. I was hoping to enhance the quality of the sound as well. At this point, I cant do either.

Any suggestions on how I can do one or both enhancements would be greatly appreciated!

Thank YOU!

I downloaded TAudioConverter but do not know how to convert the MP3 files to WAV files.

Click the “+” button to add the MP3 files (or the folder). …Since you can play the files, I’m hoping TAudioConverter can open them.



At the bottom of the window select Uncompressed WAV as your CODEC. You can also select the destination folder for your WAV files. (It will create one or more sub-folders so you might have to “dig down” a bit to find the WAV file.)

Then click “Start” (upper right), and that should do it.

The MP3 files were created using a record player that had a recording option.

Apparently, it’s making MP3s that aren’t exactly “Kosher”. Do you have a link to the specs? How does that work? Is it recording to a USB flash drive, or is it recording with a computer? Does it have a USB connection so you can record directly into Audacity?

Hi! I was able to convert the MP3 files to WAV files! Now I am using Audacity to cut the beginning and end parts that do not have any sound! How do I clear the static sound?

This is AWESOME! Thanks!

How do I clear the static sound?

With 78’s you’re never going to get “CD quality”. :wink:

Now the fun starts! :smiling_imp: For the worst clicks & pops, there are a few things you can try -

[u]Click Removal[/u]. This is an automatic effect so if you are too “aggressive” with it, you can end-up removing sounds that are not defects or otherwise damaging the sound.

[u]Repair[/u] only “touches” the audio where you identify a defect.

As a “last resort” you can try manually [u]re-drawing[/u] the waveform.

For the manual techniques it’s helpful to use the [u]Spectrogram View[/u] or Multi-view to help “find” and zoom-in on the defect.

There is a free 3rd-party application called [u]Wave Corrector[/u] that’s specifically designed for cleaning-up “vinyl” recordings. It’s fully-automatic. Or there is a $30 application called [u]Wave Repair[/u] which works “manually”.

Once you’ve done the best you can with the worst clicks & pops you can try regular [u]Noise Reduction[/u]. But listen carefully to the results because noise reduction works best when you have a constant low-level background noise… It works best when you don’t really need it. If the noise is bad, The cure can be worse than the disease.


Then try the [u]Graphic EQ[/u]. 78’s have a limited frequency range so anything below 50Hz or above 8kHz is probably just noise. Pull the sliders at both ends all the way down, and listen to the preview and just experiment to see what frequencies you can remove without damaging the music.

Then, you might want to experiment with the other frequency sliders just to see if you can improve the overall sound. (You shouldn’t have to make such extreme adjustments in the middle range). 78’s used different recording/playback equalization compared to the “modern” RIAA equalization and it wasn’t fully standardized. So IMO, it’s best just to EQ by-ear for whatever sounds best.


Assuming you’re recording in stereo, you may want to [u]Split Stereo To Mono[/u]. Any remaining noise will be “stereo” (different in the left & right channels) and making it mono may make the noise less noticeable.

And as the last step (or before making mono) run the Amplify effect and accept the default to normalize/maximize the volume.



P.S.
You might want to “archive” an original unmolested copy just in case later you feel like you’ve “over processed” it. Although, the Amplify effect won’t alter the sound quality so there’s no harm in doing that.