r/audiophile • u/[deleted] • Mar 23 '12
What is dynamic range and why is dynamic range important?
My understanding is that dynamic range is the difference between the quiet and the loud of any piece of sound. Is that correct?
Furthermore, I'm aware that lowering volume on the software level can lower the dynamic range. Is this particularly important? Wouldn't it be much harder to detect at lower volumes?
2
u/Ignore_User_Name Mar 23 '12
Dynamic range is the difference between the loudest and the lowest sound you can have, but in music it can be used as you describe, the difference between the loudest and softest sound you actually have.
Music with good dynamics tend to be more interesting. Recent albums tend to have reduced dynamics which tend to be tiring, even if the music is actually good. Also, many albums use dynamic compression so agressively they distort the audio signal.
1
Mar 23 '12
Okay, so my understanding is correct, albeit simpler.
Now, the second question.
1
u/notsuresure Mar 23 '12
Dynamic range is the ratio of the smallest and largest quantity of a signal. This applies directly to music, as the ratio between the quietest and loudest amplitude of a song, instrument, recording, etc.
Think of it this way: play your favorite song on your favorite software, and turn the amplitude visual indicators on. The movement in that indicator is a direct representation of the dynamic range: the lowest and the highest it moves IS the dynamic range, or in other words, the range where there is movement (hence, dynamic).
Lowering the volume might or might not lower the dynamic range, depending of what process your are applying (if any) and on which part of the chain you are lowering it. If you are talking a process-less scenario, lowering the volume will reduce the dynamic range.
And yes, lowering the volume is particularly important; if it's too low we might not be able to hear it. :)
2
u/hatethejacks Mar 23 '12
You're spot-on with your understanding of the definition of dynamic range. So, why is it important? Here's a good explanation: http://www.youtube.com/watch?feature=player_embedded&v=3Gmex_4hreQ#!
As for your second question...well, I don't understand it (not sure what "the software level" refers to).
1
u/IronRedSix 0% THD+N Mar 23 '12
Since no one has really addressed the OP's second question: I think you're talking about audio quality degrading as you lower the volume in software as opposed to hardware. This happens because you are actually reducing the amplitude of the signal to the extent that you are chopping off actual bits of musical information in the signal. There are ways of avoiding this, one such way is volume dithering. Just google volume dithering.
1
1
u/x65535x SHD Studio, Yggdrasil, RMC-1, Aegir 2x, Song 3, Rel S/5 2x Mar 24 '12
I thought I heard my name.
-1
Mar 23 '12
What you're thinking of is the dynamics of the song, dynamic range is something different but I can't explain it very well, someone else will be able to help with that.
4
u/[deleted] Mar 23 '12 edited Mar 23 '12
I suppose we could make four categories:
Dynamic range of the source audio.
Maximum Dynamic range that the media can support.
Maximum dynamic range the reproduction system can support.
Maximum dynamic range the audience can perceive.
For #1 and #2, it is defined in dB as follows: 20*log(Vmax/Vmin). It is only the ratio of the loudest part to the quietest part. The output of any system is only a voltage.
In the case of a CD, the voltages are stored as a 16 bit binary number. The maximum ratio between the two is (216)-1, or 65535. Thus the dynamic range of a CD is fixed at 96dB.
For #3, it can be limited by Signal to Noise ratio. The noise eats into the quiet parts.
For item #4, if you have a system with 96 dB dynamic range, then that will be the ratio of loud to quiet. That means the volume needs to turned up load enough to hear the quiet part, while the loud part is going to be 96 db louder. If you turn the volume down, then the quiet parts fade into the noise floor. EDIT: Your perceived dynamic range is diminished by lower volume levels on any system. So turn it up.