Dynamic range question, Dynamic range of hearing vs. equipment Options

[thesurfingalien]

Hi All,

I am having problems understanding the concept of dynamic range, and more specific how the dynamic range of human hearing relates to the dynamic range as specified for audio equipment.

What I have read on the Net is that the dynamic range of human hearing is, on average, 135 dB (the pain limit / threshold?).

I also understand that the dynamic range of a CD (16 bit) is limited to 96 dB, and for HD (24 bit) recordings 144 dB. This dynamic range is calculated by the bit-depth.

For playback of music (I use 44.1/16 flac only) I use a E-MU 1820 that has a dynamic range of about 115 dB (or so). I am not sure what my amp can do...

However, when I play music I hardly pass 80 dB (or so) listening volume, so the 96 dB CD data (if the recording makes full use of the range that is) gets "compressed", while the relative dynamic range remains.

After the long intro my question in essence is:

Does the human hearing have a similar "resolution" that is comparable to the resolution defined by the bit-depth in (digital) audio? Or am I just comparing apples and pears?

Regards,
Peter

[db1989]

1 bit represents 6 dB of amplitude (i.e. a doubling/halving initially, then tailing off hence the logarithmic shape of the dB curve). Ergo 16*6=96.

This post has been edited by dv1989: Jun 11 2011, 17:38

[Brand]

I must admit I have the same questions as the OP regarding digital dB and "real world" dB (sound pressure) or perceived loudness.

I've been once told that going from 0 dB to -6 dB in the digital side (PC) halves the loudness. And testing this quickly seemed to confirm it.
Now, does this mean that the sound pressure dB goes from, let's say, 80 dB to 40 dB?

Also, does perhaps the relation between the digital dB and sound pressure change, depending on the volume?

1 bit represents 6 dB of amplitude (i.e. a doubling/halving initially, then tailing off hence the logarithmic shape of the dB curve). Ergo 16*6=96.

This kind of confirms my suspicion that it's only from 0 dB to -6 dB that the halving occurs, while later a 6 dB decrease doesn't affect the loudness as much (logarithmic curve and all). But again, I'm mostly talking from some limited empirical experience/messing around. I've yet to properly grasp the theory behind this.

[lvqcl]

I've been once told that going from 0 dB to -6 dB in the digital side (PC) halves the loudness.

-3 dB: halves the power
-6 dB: halves the amplitude

Now, does this mean that the sound pressure dB goes from, let's say, 80 dB to 40 dB?

This means that the sound pressure goes from 80 dB to 74 dB.

This kind of confirms my suspicion that it's only from 0 dB to -6 dB that the halving occurs, while later a 6 dB decrease doesn't affect the loudness as much (logarithmic curve and all).

dB scale is logarithmic too.