audio formats

[armandkhambatta]

Ive been seeing a lot of new audio formats off late and I wanted to know what major difference there really is between them.
Explain this; Apple lossless and,say, WMA lossless are both formats that seek to keep the audio quality of the disc contents unchanged; yet on the same song, WMA encodes at 300-400kbps, while Apple does it at 700-800kbps.Thus the bitrate, as well as the size of the music folder ,is totally different, and both supposedly have the same output.
Also, lossless formats use upto 10 times the space on my ipod, and frankly, after 320 kbps I cant tell the difference. And I dont see any major major lax in quality at 256kbps mp3. Is there a real audibile difference.Does it only tell on mega expensive audio equipment? Also,correct me if I'm wrong, I think after a point the human ear can't tell the difference. Is there any such "swarchzchild radius" for the ears beyond which the nuinces make no difference? I'm puzzled.

[noddin0ff]

Bit rates should not be relevant on lossless encoding. However, I do see a bit rate listed on Ale files. I'll take a guess. I believe the bitrate for redbook CD PCM audio is 700kbps per channel, or 1400kbps for stereo audio. If your file is compressed to half it's size, you only need to encode 700kbps to contain 1400kbps of information. The amount of compression you can achieve varies with the kind of sound being encoded.

WMA can be both a lossless and a lossy file format. I suspect you are using WMA as a lossy compressor, but I could be wrong. The file size for WMA lossless is similar to other lossless applications. Here's a comparison to APE (http://www.ntu.edu.sg/home5/PG03053527/Tips/LosslessAudioCodecs_WMA_vs_APE.htm) and here's a comparison of many lossless formats but not WMA (http://flac.sourceforge.net/comparison.html)

The size of a lossless file can vary with the application, but not by as much as you seem to observe, suggesting you are not looking at lossless encoded files?

Is there a difference between a lossless file and a compressed file? Yes. One has discarded information.

Can you hear the difference? Depends. Depends on the quality of the encoding, on the quality of decoding, the quality of the system, the quality of your ears, the ambient noise around you, and your experience in knowing what to listen for. There is a point beyond which you can distinguish, but a person can train themselves to distinguish more than an untrained person would in just about any endeavor.

[Sir Terrence the Terrible]

The data rate for CD is 750mbps per channel or 1.5mbps total

[armandkhambatta]

Bit rates should not be relevant on lossless encoding. However, I do see a bit rate listed on Ale files. I'll take a guess. I believe the bitrate for redbook CD PCM audio is 700kbps per channel, or 1400kbps for stereo audio. If your file is compressed to half it's size, you only need to encode 700kbps to contain 1400kbps of information. The amount of compression you can achieve varies with the kind of sound being encoded.

WMA can be both a lossless and a lossy file format. I suspect you are using WMA as a lossy compressor, but I could be wrong. The file size for WMA lossless is similar to other lossless applications. Here's a comparison to APE (http://www.ntu.edu.sg/home5/PG03053527/Tips/LosslessAudioCodecs_WMA_vs_APE.htm) and here's a comparison of many lossless formats but not WMA (http://flac.sourceforge.net/comparison.html)

The size of a lossless file can vary with the application, but not by as much as you seem to observe, suggesting you are not looking at lossless encoded files?

Is there a difference between a lossless file and a compressed file? Yes. One has discarded information.

Can you hear the difference? Depends. Depends on the quality of the encoding, on the quality of decoding, the quality of the system, the quality of your ears, the ambient noise around you, and your experience in knowing what to listen for. There is a point beyond which you can distinguish, but a person can train themselves to distinguish more than an untrained person would in just about any endeavor.
Thanks LOADS! Thats the most comprehensive reply ive ever received! thanks for your time
oh, and how do you" train yourselve to distinguish more than an untrained person would" vis a vis audio?

[noddin0ff]

Thanks LOADS! Thats the most comprehensive reply ive ever received! thanks for your time
oh, and how do you" train yourselve to distinguish more than an untrained person would" vis a vis audio?
You're welcome. Glad I could help. As to 'training' I don't really mean it in the sense of you hear better the more you try, like you get stronger if you lift weights. By training I mean becoming more aware of what to listen for. For example, sibilance. When I was researching my speaker purchase I kept reading comments about 'sibilance'. I had no idea what that was. But I looked it up. It's a more pronounce 'ess' sound in speech. I'd never noticed it before in speakers. But, after I found out that it exists and knew what it should sound like, I started listening and sure enough I could hear diffences I never noticed before. I trained myself.

Another analogy with with video. Progressive scan is supposed to eliminate 'jaggies' caused by alternating scan lines from interlaced signals. Most people don't notice them. But once you know intellectually that they are there and what the look like, you notice them all the time because you've trained yourself where to look for them.