Popular Audio Formats Tests

Audio Format Test Results – MP3, WMA, OGG, VGQ and MP3Pro
In fact, no one expected such a result: of course, everybody thought that the manufacturers’ promises about “almost CD-quality” or even “CD-quality” were pure fiction but one could suppose that the different audio-formats do not differ that much concerning sound-quality. But that’s especially where some noticable differences arise. Right now there are two high-end-formats at the very top that have been sadly smiled upon a few years ago. The lowest-quality format of the ones tested is however the long-proven MP3.

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How choose right bitrate?

The sound clearly lacks definition: as an example, hall’s noises are perceived as some breath. The result is comparable to a good FM radio.

The sound seems less present and less natural than the original. The definition is a bit less good, the voice is less clear. Attacks are less spontaneous. The spatialization is different from the original recording: the sound seems to be located more far and more lower. There is however a very noticeable improvement compared to 96kbps.

Hall’s noises are slightly less defined than the original. The violin is a bit less present and the piano attacks a bit less sharp. The voice is nearly identical to the original recording but sibilants are less pronounced. We can notice the same spatialization problem as with the 112kbps’s one although there is again a good improvement compared to the 112kbps rate.

The sound is more natural than 128kbps but the improvement is less spectacular than during the two preceding stages. The sound is different from the original, without however being possible to tell in what. I think that the difference resides more in what we feel rather than in what we hear.

The sound is not felt as the original recording. It is however totally impossible to tell in what.

The sound is indiscernible from the original. It is impossible to make the difference with the original recording.

The sound is indiscernible from the original. It is impossible to make the difference with the original recording.

CD Audio
The sound of the burned CD is strictly identical the manufactured CD. This test, although it could appear useless, is however necessary so in order to insure that it is impossible that the burning step introduces differences, that would have falsified tests. It is clear that the 128kbps rate does not produce a quality equal to a CD on a good quality Hi-Fi installation. We can wonder if Fraunhofer’s institute has not made an error by limiting its ACM pro codec to 128kbps. However, in the context of a computer use, the quality is equal to the one obtained by reading an Audio CD on a CD-ROM reader. The quality at 128kbps is also indentical to the one obtained with the original CD on a mini or midi Hi-Fi installation, and on the vast majority of Hi-Fi installations in separated elements. The test equipment is indeed better than the majority of Hi-fi installations. Conclusion : For a computer use, the 128kbps rate produces a quality equal to an audio CD. But in the case of an MP3 use in advanced Hi-Fi, it is necessary to use a 256kbps bit rate to reach an identical result to the CD sound.

How to Remove Vocals from MP3s, Ogg or WMA Audio Files

This is definitely a difficult task, but there may be some hope! 🙂

Here’s the little trick. You will need an external sound mp3 editor such as CoolEdit.

The trick is to rely on the fact that vocals are usually positioned in the “center” of the stereo field. (Balanced between the left and right speakers).

Unfortunately, there are usually other artifacts such as reverb and effects which are usually panned to one side.

You start with a stereo file and end up with a mono file with the center frequency cancelled. Its not very good for most songs…but it does work for some. This process is also known as the “OOPS effect” as it cancels frequencies.

Here’s how its done with CoolEdit:
Load the WAV/MP3 file into Cool Edit.
Create a new window with no WAV file in it (File->New…).
Set the settings at 44.1KHz 16-bit *mono*.
Switch back to the original WAV/MP3 file (with the “Window” menu).
Select the entire left channel in the original WAV file. If you move the mouse to the top of the WAV display area, the mouse cursor gets a little ‘L’ next to it. Pick a spot near the middle of the screen, left click, and drag all the way to the left edge. Then move the cursor back to the middle, right click, and drag all the way to the right edge. You should now have the entire left channel selected.
Select “copy”. Switch to the new WAV file, and select “paste”. Switch back to the original.
Move the mouse cursor near the bottom of the WAV graphic until the mouse pointer gets an ‘R’ next to it, and select the entire right channel the way you did the left.
Select “copy”. Switch to the new WAV file. From the Edit menu, select “Mix paste…”.
Select “Overlap (Mix)”, volume of 100, and check the “Invert” checkbox. Click “OK”.
Give this a try to see how it works for you. You may want to just try looking around the ‘net for an “instrumental” version of the song (if it is available).