When i want to listen to music on my computer, i usually just pop a CD in the drive and play the whole thing. However, i have some songs that i’d like to keep on my hard-drive permanently, and am wondering about the best way of turning them into mp3 format.
I have Musicmatch Jukebox v. 7, and in mp3 recording it offers the following modes:
Fixed setting 160kbps
Fixed setting 128kbps
Variable Bit Rate, choose from 1-100%
Constant Bit Rate, from 8kbps to 320kbps
Now, it seems obvious to me that one of the last two is the best option, but i’m not sure which one gives the best results. Can anyone help me, and maybe explain some of the theoretical and practical differences between VBR and CBR?
I know what kbps signifies for CBR, but what does the percentage mean for VBR?
I’m not sure about you being able to choose an option of 1-100% for VBR. It was my understanding that when encoding an MP3 using VBR, the encoder determines what the best mode/ratio/percentage of audio compression (which is what makes mp3s smaller than wavs) for each frame or some other short period of time. Thus, each interval has a different kbps value.
The first time I played a VBR mp3 with WinAmp, the value in the kbps window went nuts, like it was a slot machine. I thought something was wrong until I read about VBR on the internet.
I don’t know what the difference is between your two fixed settings and a constant bitrate set to the same value.
It’s been my experience that the 160 kbps level is really the minimum encoding level for nice sounding mp3s. I’d recommend 192 or higher. You should also look into other audio compression formats, like ogg, flac…do some research before you start moving your collection to digital.
VBR is the best if you will just be using the songs on your computer. IIRC, the only reason not to use VBR is that some portable players don’t handle them well.
I can’t say that I understand what the percentage is, unless that’s the percentage by which it would be compressed? But that doesn’t make much sense either, as why would you make, say, a 70% mp3 when you could just use FLAC or some other lossless codec.
The only time I’ve ever encoded to VBR mp3s the options were given as an average bitrate and a minimum bitrate, both of which make sense to me.
Personally, I have a low opinion of anything that MusicMatch makes. Try LAME, I’ve heard it’s the best mp3 encoder out there, and it’s free!
Well, next to the VBR setting is a slider that goes from 1-100. This is what the instructions say about it:
To tell you the truth, it probably doesn’t matter too much if my mp3s are of the greatest possible quality. I have no mp3 player outside of my computer, and it’s just nice to be able to listen to music while i work.
I recorded a song of about 5 minutes in length using CBR@320 and VBR@100. The CBR version is 13Mb and the VBR is 9.7Mb. On my speakers, i couldn’t really tell the difference in quality between the two.
Thanks for the links and the suggestions. I’ll keep them in mind if/when i decide to really go digital.
There are two types of VBR encoding in MP3s, ABR and VBR. ABR is Average BitRate, where the MP3 encoder dynamically increases and decreases the bitrate, trying to maintain an average bitrate that you specify over the length of the file. This gives you better file size predictability, but the downside is that the encoder can only average over a few seconds of the file at a time, so periods of very complex audio can break the rate control, thus resulting in reduced quality or oversized files. An ABR file should still always sound better than an CBR (Constant BitRate) file at the same size. VBR, Variable BitRate, compresses to a quality setting, rather than a size. VBR uses no rate control, simply compressing each frame as much as possible while still keeping distortion below a value determined according to your quality setting. VBR is the most efficient and best quality method for encoding MP3s.
Musicmatch Jukebox is known for being a rather poor quality MP3 encoder, in addition to having substandard ripping features. I would suggest you try CDeX, the most accurate ripper around. It includes the LAME MP3 encoder, which is the best MP3 encoder available. It will also allow you to encode to OggVorbis, a free and open replacement for MP3 that offers significantly better quality.
This may be heading a bit off-topic here, but if you’re concerned about quality, why use MP3 at all? Reasons to use MP3:
[ul]
[li]You want to share files, and compressed files transfer faster[/li][li]You want to use the files with a portable MP3 player[/li][li]You want compressed files due to limited hard drive space[/li][/ul]
From your OP, it doesn’t sound like you want to share these files or use an MP3 player, so unless you are limited in your disk space, why not just store your music files as WAVs? The sound quality is much higher.
I know WAV quality is considerably better, which is why i have, up until now, just been listening to my CDs in the CD-ROM drive.
The issue for me is hard drive space. My computer is over two years old and only has a 20gig HD, and with all my programs and essential files installed my free space is only about 14gig. In my current financial situation a new computer, and even a new hard drive, are not an option. Even if i didn’t want to leave some HD space for things like images (i have a digital camera), i could still only get about 28 CDs on the drive using WAV. One of these days i’ll have a 200gig HD.
Thanks for the advice, Alereon. I’ll give CDex a try.
I’ve been using CDex for some time now and was amazed that the quality of the resulting file compared to the ripper I had been usind(and for which I had paid!)
I’ve no idea what LAME stands for, or why it should be so much better, if a litle bit slower on high bitrate conversions, but I would recommend it.
LAME stands for LAME Ain’t an MP3 Encoder. Of course, the name doesn’t make any sense as it now IS an MP3 encoder, but there you go.
From the LAME website: “Following the great history of GNU naming, LAME originally stood for LAME Ain’t an Mp3 Encoder. LAME started life as a GPL’d patch against the dist10 ISO demonstration source, and thus was incapable of producing an mp3 stream or even being compiled by itself. But in May 2000, the last remnants of the ISO source code were replaced, and now LAME is the source code for a fully LGPL’d MP3 encoder, with speed and quality to rival all commercial competitors.”
With a variable-bitrate encoder, the encoder automatically changes the sampling rate depending on the complexity of the music. If you have a quiet or silent passage in a song, there’s no need to encode this part at 320kbps because it creates a lot of wasted file space for no good reason. So, the encoder drops the sampling rate way down to keep the MP3 file size smaller. When the music complexity picks up, the encoder raises the sampling rate to keep up. You get the best of both worlds: smaller file size, but good quality where you need it.
Some words on why LAME is the best MP3 encoder around. The main reason is excellent psychoacoustic modeling. Psychoacoustic modeling is what an MP3 encoder uses to determine which parts of the audio you can hear most clearly, thus need to be encoded with the most accuracy, and which you can’t hear, thus can be heavily compressed.
LAME also has great channel coupling. Channel coupling, also called Joint-Stereo, is where, instead of encoding two channels for a stereo MP3, one channel is encoded, then the differences between that channel and the second channel are recorded, allowing the MP3 decoder to reconstruct the second channel during playback. The advantage of channel coupling is that it is much more efficient, the disadvantage is that poor encoders can remove some of the stereo effect. Most MP3 encoders, such as the Fraunhauffer reference encoder, switch to true stereo mode above 192kbps to avoid problems due to channel coupling. With LAME, even at 320kbps, the gains from improved compression efficiency allow a Joint-Stereo MP3 to sound better than a true Stereo MP3.
