In certain fields (e.g.; the Year field) in the mp3 tag displayed by File/Edit Metadata that has a numeric value (e.g.; 2015, I haven’t tested letter values) and then saved, shows up in other tag editors as “2015\2015”. Why (Windows 7 sp1, Home premium)? Also, does using Audacity as a tag editor (i.e.; opening a mp3 and immediately exporting it again and modifying the tag when shown the metadata screen) degrade the audio portion if saved in the same format (e.g.; variable bit rate 4)? (Fyi; I am using lame-enc.dll 3.99.3 as the encoder, same thing happens with lame_enc.dll 3.99.5)
Yes it does.
Audacity is not a “tag editor”, it is an “audio editor” with support for metadata. To be able to do all of the fancy audio editing and processing that Audacity does, audio files need to be uncompressed “PCM” audio data. That means that MP3 files need to be decoded when they are imported. When Exporting an MP3 from Audacity, the audio data is (re-)encoded to MP3, which always loses some audio quality.
There are many different standards for metadata; id3v1, id3v1.1, id3v2, vorbis comments, RIFF chunks, metadata at the start of files, metadata at the end of files, …
Different applications support different standards, making it near impossible to support all formats for all software. Audacity just supports some of the most common metadata formats. To get full support of metadata for a particular program, you should use do tagging in that application.
There are also 3rd party applications that are specifically designed as tag editors. These tend to be more full-featured than Audacity for handling metadata, for example, MP3tag http://www.mp3tag.de/en/ (watch out for misleading adverts on that website - particularly “big green download buttons” that link to other software - to download, use the appropriate text link on the download page).
There are also 3rd party applications that are specifically designed as tag editors. These tend to be more full-featured than Audacity for handling metadata, for example, MP3tag > http://www.mp3tag.de/en/ >
I also recommend and use MP3tag, and couldn’t do without it today. Best IMHO to examine and edit tags at a `folder level´ with MP3Tag, so all files can be viewed and edited for uniformity, etc.
While we’re on a `folder level´ discussion, I recommend BRU http://www.bulkrenameutility.co.uk/Screenshots.php.
Because we save Year (and Comments) as both ID3v2.3 and ID3v2.4 tags, so we don’t get complaints about tags not being visible in apps that only see v2.3 or apps that only see v2.4.
The app you are using sees both v2.3 and v2.4, but we get fewer complaints about that than if we only write v2.3 or v2.4. 
Gale
Update: this may be a Mp3Tag bug and I have opened the topic there,
It’s only an Mp3Tag bug if you are arguing they should not show two tags with the same value, or should do something else instead.
Gale
Well, I’m not sure your criteria for a bug is mine. It seems to me that when I enter data into a field that is what should appear in that field, no matter which program i use…
I was going to suggest you add an option to save metadata without exporting the audio portion, but I learned from your reply that things are not so simple. Also, I hope others heed your warning about the Mp3Tag site and the ubiquitous “huge green arrows” and all the other ads there (“noise”). Despite being someone who is more sophisticated than the “average” user, I got caught by malware/adware masked as being the latest Mp3Tag installation file. Go to the Download choice on the top menu bar of the Mp3Tag site for the legitimate program. I’ve spent many hours fixing the carnage done to my computer (yes, I think I’ve been able to remove the offending program(s)) when I downloaded and tried to install a seemingly legitimate file [NB: Stay away from Softonic (sp?) software.]
Also, it would be very helpful, as some sites do (e.g., Amazon reviews) to notify me by email when someone replies to a post of mine. BTW; thanks for all your (free) time. No wonder Audacity is such a venerable program.
Until all software uses the same metadata standards, that is an unrealistic expectation.
Some applications use ID3v2.3 tags and some use ID3v2.4 tags. The only way that we can ensure that the tag shows up in both cases is to write both versions of the tag. MP3tag show both versions of the tag. Considering that MP3Tag is a specialist metadata editor, I think that is the correct behaviour.
I’d suggest that you install a good ad-blocker to your web browser (I only noticed the adverts by deliberately turning off my ad-blocker), and get some good security software installed that can catch malware before it does any damage.
At the bottom of this page there is a “subscribe” link. Click that to be notified by email of replies.
Yes, Florian Heidenreich of Mp3Tag (the developer of Mp3Tag, I think) also recommended using an ad blocker. It is something I’ve avoided (both for philosophical and more practical reasons) but I will trepidatiously look into them; since I download and examine many open source programs, the problems I’ve had with malware/adware may be compounded in today’s internet.
Yes, I also view Mp3Tag as the best tag editor available (at least of the few I’ve tried, and even considering the small tag editor I’ve written.) Perhaps, given the evolving mp3 tag standards, this is the best that can be hoped for.
Finally, thanks for the subscribing tip. I have done so…
You should be subscribed by default, unless you changed it by accident.
Gale
You could consider Ninite https://ninite.com/ which installs and keeps updated the apps you select without having to visit web sites or use misleading installers that bundle crapware. It does not include Mp3tag.
If you use Firefox you could consider NoScript - JavaScript/Java/Flash blocker which is in effect an ad blocker as well. It is very customisable but many sites won’t work fully of course with JavaScript disabled.
Gale