to the point!

[armandkhambatta]

which is the best audio format and why? im using mp3 320kbps. also, whats a sample rate and how does this whole bitrate thing work anyway?
sir terrance, maby?

[noddin0ff]

A bit is just a unit of digital information. A 'O' or a '1'. The bit rate is how many bits are transferred per second. The more bits per second the greater the resolution. Sound can be described as a wave form which has varying amplitude over time. When you make sound digital you don't describe the wave (which has an infinite number of points along it) you describe a fixed number of points along that wave. The sampling rate is the number of points per second of the wave. Audio CD samples at a rate of 44.1 kHz. Which means, 44,100 points on the wave per second are represented. Each point is turned into a 16bit binary number. 16 bits x44,100 points per second = ~700,000 bits per second = 700kbps. There's more bits of information on a CD than just the 16 bits refered to, so TT's 750kbps figure is likely accurate for all the data transferred.

When you compress, you discard information, decreasing the resolution and decreasing the number of bits per second needed to transmit the information. I don't believe it is necessarily a direct relationship but what this approximates is a reduction in the number of points per second sampled along the wave. A 128kbps file retains fewer points along the line than a 320kbps file. When the file is converted back into music, a program has to guess what the wave between the points should look like. Fewer points per second = smaller file size = more guessing = more error = lower fidelity.

The better programs will make better guesses as to what points to discard when encoding and give better clues as to how to guess at the wave between the points. And they will do this faster and more efficiently. Which one is best is debatable. Someone else can give opinions on that. At similar lossy bit rates the differences are subtle, perhaps subjective. At a given bit rate, file sizes may vary a little but not so much that it makes a big difference. When you are talking lossless, it is not so much an issue of quality so much as speed and efficiency. The best bit rate/format is one that fits what you want in the amount of space you have, in the amount of time you have, and sounds fine to you.