# High energy coefficients in 1d DCT for audio

I've been reading a little bit about how DCT works in image compression using the 2D transform, however I don't know how this applies to audio using a 1D transform.

Suppose I have an audio segment, I mean, some samples of a mono audio vector.

Ai = [-0.0288,-0.0304,-0.0354,-0.0406,-0.0469,-0.0518,-0.0647,-0.0831 ...]


And then I calculate 1D DCT on that vector.

R = dct(Ai)


The result would be something like this:

0.2143   -0.3158   -0.6354   -0.3877    0.5503    0.2330   -0.1690    0.0203


How should I interpret this result? Are the high energy coefficient the ones with a greater value?(I'm still a noob on this). Is the first value the DC coefficient? Is there a special way to read the vector (zig-zag or something)?

Any help will be appreciated, btw I'm working with matlab. Thanks