The old version of LAME (3.99.5) encodes better than the current one (3.100)

LAME - MP3 creation
1

For years I used old versions of Audacity that worked with LAME 3.99.5 and exported music files in mp3 format at 128kbps resolution. Being a compressed format, I assume there is a loss of quality, but for me it was imperceptible to the ear.

Now that I have a new computer I have updated Audacity to the latest version (3.1.3), which incorporates the latest version of LAME (3.100). However, when exporting music in mp3 format at 128kbps I was very disappointed, because with the new version of LAME I clearly hear the loss of quality.

To make sure it wasn’t a kink of mine, I’ve tried importing and exporting the same music file five times in succession with both versions of LAME, using both the old and the new computer. The result is that in both cases there is an obvious deterioration in audio quality, but the loss is much more serious using LAME 3.100. To my knowledge, the test result confirms that the latest version of LAME encodes worse at 128kbps compared to the previous one.

The problem is that Audacity 3.0.3 embeds LAME 3.100 into the program and doesn’t allow you to use LAME 3.99.5. Therefore, to export music in mp3 format at 128kbps I will have to install an old version of Audacity on the new computer, hoping it will work. I don’t see any other solution. It’s a shame.

2

Hi! I will contact someone I know on the team and let them know. Thank you for your report!

3

Hi, I see you got some answers on the audacity forum already: The old version of LAME (3.99.5) encodes better than the current one (3.100) - Audacity Forum (audacityteam.org)

4

Yes, and I appreciate the attention of the two people who have answered me. However, the problem is not with the Audacity program but with the LAME encoder. I hope that my comment reaches the developers and in future versions they can correct the problem.
Thanks to you also for the attention given and greetings.

5

Can you substantiate your quality claim with any additional hard facts?

6

As I have explained in the Audacity forum, for me, the poor quality of the files exported with LAME 3.100 at 128kbps is due to the fact that I detect the typical artifacts produced when the resolution is insufficient, artifacts that I have never detected exporting with LAME 3.99.5 or even trying at 96kps, although I always save the files at 128kbps to avoid that minimal loss in the passages with percussion instruments.

In other words, on the whole, music encoded with LAME 3.99.5 at 96kbps sounds better to me than with LAME 3.100 at 128kbps. It is a pity that the latest version represented a loss of quality and not an improvement.

7

96kbps shows always substantial artifacts on high frecuency percussion like crashes, hihats, etc. 128 is way better, but still I can also discern artifacts there. Have you tried 160kbps for a comparison? I am interested in your experiences.

8

First of all, I have to rectify a mistake. The version of LAME that I have on my old computer is not 3.99.5 but an earlier version, 3.98.2. Therefore, I should have titled the message “LAME version 3.98.2 encodes better than the current one (3.100)”.

I have carried out the test that you suggest at 160kbps with LAME 3.100 and, as expected, the quality improves, although technically it does not exceed the result at 128kbps using LAME 3.98.2.

I say this because later I have carried out another test that seems more objective to me: recoding the audio five consecutive times using the two versions of LAME at 96, 128 and 160kbps. The result has been that, in all three resolutions, the file recoded with LAME 3.98.2 loses less quality, after being imported and exported five times.

In addition, the loss of quality is not of the same type, it does not have the same texture. Using LAME 3.98.2, the audio obtained after the five re-encodes reminds me of the quality of an old telephone line: music loses brightness and treble. Instead, using LAME 3100 the result reminds me of the quality of a worn and wrinkled cassette tape: the audio is clearly flawed by the amount of artifacts it contains. I think nuance is important and explain why.

The small loss of quality generated using LAME 3.98.2 at 96 or even 128kbps does not give me rejection to the ear because I do not perceive artifacts and, therefore, I do not detect it unless I compare those files with others of higher resolution, listening to the same passage at both resolutions, and even then I find it hard to tell the difference.

On the other hand, using LAME 3,100 I clearly perceive artifacts even at 128kbps, and that does cause me rejection because for me it is defective audio. Only starting at 160kbps is listening pleasant, while with the old version I get the same result at 128kbps, which produces smaller files.

Therefore, in my opinion, the difference is in the perception or not of artifacts. If I do not perceive them, the audio sounds good to my ear despite the loss of quality with respect to the original recording. On the other hand, if I perceive artifacts, the hearing is unpleasant and I have to discard the file as defective.

For me, an efficient encoder is one that allows you to lower the resolution of the audio and obtain smaller files without detecting the loss of quality generated. So far, in my experience, LAME version 3.98.2 is more efficient than 3.100.

9

Following a reply on the Audacity forum, I’ve run two more tests which, to my knowledge, shed some light on the cause of the problem.

I have re-encoded the same file five times following the above procedure, but using one version of Audacity to import it and the other to export it. I explain it in detail.

In the first test, I imported the file with Audacity 2.0.3 and saved it as a project (.aup file), then opened it with Audacity 3.1.3 and exported it as .mp3 at 128kbps (with LAME 3.100). I have repeated the operation five times.

In the second test, I imported the file with Audacity 3.1.3 and exported it as .WAV format so I could open it with Audacity 2.0.3, and then exported it as .mp3 at 128kbps (with LAME 3.98.2). I have also repeated the operation five times.

The result is as follows:

First test: the final file imported with Audacity 2.0.3 and exported with LAME 3.100 (Audacity 3.1.3) sounds the same as the final file imported with Audacity 2.0.3 and exported with LAME 3.98.2 (Audacity 2.0.3). The sound resembles that of an old telephone line.

Second test: the final file imported with Audacity 3.1.3 and exported with LAME 3.98.2 (Audacity 2.0.3) sounds the same as the final file imported with Audacity 3.1.3 and exported with LAME 3.100 (Audacity 3.1.3). The sound resembles that of a worn and wrinkled cassette tape.

It seems clear, then, that the difference is not in the version of LAME used when exporting the file, but in the version of Audacity used when importing it. To my knowledge, this does not show that Audacity 3.1.3 imports .mp3 files with poorer quality, but it does show that the sum of the processes of importing and exporting .mp3 files at 128kbps gives better results in Audacity 2.0.3 than in Audacity 3.1.3.

10

This is a very interesting find! I appreciate all the dedication into providing feedback on both forums. Let’s see if someone else can run similar tests and confirm the results. Cheers!