Until recently I was using Mp3 Tag Tools to rename/move mp3's after ripping them with EAC. Everything had been working fine. But the other night I started using fb2k's masstagger for this. Somehow, though, the ID3 tags have become corrupt or something. If I look at an mp3's properties in foobar - either the normal dialog or the 'Show File Info' dialog - the tags aren't shown. I just downloaded TagScanner and it isn't showing the tags either. And yet Mp3 Tag Tools still loads all the info for my whole collection. Windows Explorer also shows the correct info if I hover over one of the mp3's.

So obviously the tag information is still there. But what I need to know is how to fix them so foobar will read them. Any ideas what went wrong and why some programs are still reading the ID3v1 tags correctly? Is there a program that will scan for problems in my files and maybe fix them?

You haven't by any chance used used mp3gain have you? Also, what option have you got selected in Preferences > Playback > Input > Standard inputs ?

By default foobar reads apev2 tags first. If these are present but empty it won't show any tags.

So does masstagger add APEv2 tags when renaming files, if fb2k is set to write them in the 'Standard Inputs' prefs? Because I'm guessing the problem occured from both masstagger and mp3gain writing an APE tag, and only the last is picked up by the programs.

Um, APE tags on an MP3 is questionable at best. They are incompatible with most players both hardware and software.

The replaygain function in foobar is excellent.
It however is not usable in other devices or software.

If you use MP3Gain without the APE tagging, it does no harm to your MP3s and allows the gain to apply on any device that plays MP3s.

well, depends what you mean by harm. It does change your mp3s and it does technically reduce the quality.

The problem is that mp3gain writes the gain information to apev2 tags but in doing so clears all other apev2 fields.

This sounds funny. I doubt existing APEv2 tags with tag details would be wiped out because of mp3gain.

QUOTE(donnie @ Jan 3 2006, 07:29 AM)
well, depends what you mean by harm. It does change your mp3s and it does technically reduce the quality.


I disagree. Change can be be benign, and "lost" quality can be regained by raising the volume, so is not lost at all. The quality can actually rise, if clipping had originally occurred.

Question
7/12/2001, 9:52 pm

Matt wrote the following on the Monkey's Audio Message Board:

Well, keep in mind that you can only store amounts to turn tracks down, not up. Peak level normalisation (already in MAC), provides the most you can safely turn a song up without clipping, but this obviously doesn't even begin to solve the problem you're working on.

So, you'll need to actually store something like -12dB for the loud songs, but this is essentially the same as throwing away data. (thus introducing noise)

Answer
Agreed. But let's assume people really want to solve this problem. From the thousands of posts I've seen on various message boards requesting this very feature, it's clear that they do.

To maintain full dynamic range, the ideal solution is to feed the Replay Level value out of your PC, to your volume control. Obviously this requires dedicated hardware, and few people are going to do this, but it would be possible for those who demand highest quality to put an end to stupid fluctuations in level in this manner. No compromise. No downside. It'll appeal to Monkey's Audio users!

The (compromised?) solution we can offer now, to everyone, is to do what you suggest above - just turn the loud tracks down in the digital domain. With the standard I've proposed, it drops the level of a hard limited pop track by about 10 dB. There are two reasons why I don't think this is a serious problem:


Such a track already has a highly compressed dynamic range. Most of the energy was within -3dB of the peak. Now it's within -13dB of the (system) peak. Still way way way above the noise floor of even the worst soundcards.
Dropping 10dB is equivalent to losing 1.5-bits of resolution. The input data is likely to be 16-bit (with a CD source). You, and many others who care about sound quality, own 24-bit sound cards. The dynamic range is about 110dB. The noise floor of the original recording, even after being dropped by 10dB, is still the limiting factor - you're not going to loose anything in a 24-bit replay system.
I realise the absolute highest fidelity possible when feeding a 16-bit source to a 24-bit sound card is to send it as-is, to occupy the top 16-bits. So whatever else you do is a compromise. Well - if you feel like that, go and build the hardware I've described to alter your volume control according to the Replay Level!

But in reality, a consistent replay level (an advantage which EVERYONE can appreciate) will outweigh the problems of digitally scaling the data (which is a problem that 0.01% of listeners are going to notice).

ummm, I'm pretty sure they are. If you take tracks that you've previously played in foobar and replaygain them using mp3gain then all the fields appear blank when you open foobar. If you then remove apev2 tags the id3 tags will show.

I've just checked, and it's true.

Consequently, it would be wrong to say that mp3gain clears all other APEv2 fields.