MP3 quality - BIG help

[Warthog]

I was looking at the recording options in Music Match recently. The best quality was 160kbps w/oversampling. What is oversampling and why is that quality better than 128 (they say they are both "CD Quality")? I don't quite understand the "kbps" part. Kilobytes per second? What does that have to do with music?

The mp3s of Creed's "Higher" and Pearl Jam's "Last Kiss" (both from Napster) are 320kbps and 256kbps respectively, according to Real Jukebox.

Their is also Custom Quality at the bottom. What is "VBR" and "CBR"?

Help please?

Warthog

[seti]

I can awnser some questions...

The bit rate of the song(kbps)is basicly the quality of encodeing. The higher this number is, the less audio information has been subtracted from the cd version.

CBR, is constant bit rate. You find this almost everywhere.

VBR, is varible bit rate. The encoder analysis the data and tries to figure out what is important and what isn't important in regards to the audio data present on the cd copy. It encodes at the bit rate that will give the listener the best reproduction of the original sound at any time durning the song. That's kind of a hard one to explain, and I don't feel I explained it well.

I don't know what over sampling is. http://sysopt.earthweb.com/forum/frown.gif

[This message has been edited by seti (edited 05-26-2000).]

[Szech]

I don't like variable bit rate. I've burned CDs of MP3s that had variable bit rate, and I think it defaulted to the lowest quality that was present in the MP3. I'm not sure what exactly happened, but the CD came out horrible. As for what bitrate to choose, I use 128K myself, because I can't tell the difference between that or anything higher. I guess some people can, so they use 160K.

[Joel Kleppinger]

I personally LOVE vbr. Maybe I can't always hear the difference on my PC speakers, but I DEFINITELY can when I burn those mp3s on a CD and play it on my car stereo or portable CD player.

BTW, when burning on CD, create a playlist that you want on that CD then use winamp's diskwriter to output it to disk, then burn the wav files. It's definitely the best way and you can customize the EQ settings.

And no, I really can't guess what oversampling is. But with AudioCatalyst, I use VBR/Highest Quality. It usually is 160-224 kbps, but it'll frequently go much higher, depending on the complexity of the sound of the song. It really does a good job.

[OuTpaTienT]

Wart,
read this to learn about oversampling: Digital Audio: Oversampling (http://www.pan.com/earlevel/Digital%20Audio/Oversampling.html)


I thought I knew what it was, but I learned a bit by reading that. The main site that page comes from is Digital Audio (http://www.pan.com/earlevel/Digital%20Audio/), and has a few other good pages on various aspects of this subject.

---------------
Oh, BTW (just personally) I always rip CDs using at least 160kbps and more often than not 192 or 225. Usually at 225kbps and over you can use true stereo mode and not "joint" stereo mode whichs can sometimes cause a phasing problem. I too like VBRs, but definitely must be done at HQ.

[This message has been edited by OuTpaTienT (edited 05-26-2000).]

[Warthog]

Thanks very much guys! http://sysopt.earthweb.com/forum/smile.gif

I'll try out the VBR sometime. I have large home theater speakers hooked up via amplifier to my pc, so I dont' think the problem of not being able to hear the difference will be relevant.

Outpatient, that is a very good link. Helped me understand it a bit better. http://sysopt.earthweb.com/forum/smile.gif

Warthog

[Warthog]

Alrighty, I did a test.

I had a song recorded in "Near CD Quality" (96kbps), VBR 100% (78kbps) and "Full CD Quality" (160kbps). I used Music Match for this, listened to the first 20 seconds or so of the song and kept the volume at the same level.

Out of the three, VBR was by far the top. It definately had clearer, more "like-I-was-there" vocals, MUCH punchier bass and I could easily hear other intruments that were not present before. 160kbps did not lack behind by much but there was still a clear difference. 96kbps was not acceptable according to my standards. It is not very clear at all and doesn't put out as much bass.

The downside of using such high quality was that the song took up more space:
VBR - 6.2mb
160kbps - 4mb
96kbps - 2.4mb

Keep in mind that this test was done by my speakers described above - not dinky generic pc speakers.

Just lettin' you guys know. http://sysopt.earthweb.com/forum/smile.gif

Warthog

P.S. - FYI the song was "Breakfast" by the Newsboys. It was 3:40.