Hello everyone, I love this forum and I am trying to learn how to read all Amir’s measurements, starting from the basics.
But nothing has caused me as many headaches as the concept of dynamic range, and I can’t seem to wrap my head around it by myself anymore. Having to also translate from English, there are still many points that aren’t clear to me.
I would like you to help me understand if my reasoning is correct and, if necessary, correct me on the bolded parts.
1. 116 dB is our best-case hearing dynamic range. Perhaps because the ear acts as a compressor of the dynamic range? Since the dynamic range of hearing is 140 dB (we can hear from 120/130 dBSPL down to -10 dBSPL) but this wide dynamic range cannot be perceived all at once. Is that correct?
2. 108 dB (18 bit) is the best-case scenario for music resolution. But, unless it’s computer-generated music, we must take into account the electronic noise from the recording microphone (16 dBSPL?), so 108-16 = 92 dB (15 bit). Is that correct?
3. The rule of thumb is that our audio devices should have a DR 10 dB higher than that of the music, so 108+10= 118 dB (19.6 bit).
4. The noise in my listening room is about 20 dBSPL, at best:
If I want to consider peaks at 110 dB (classical music), could I achieve this with a DR of 72 dB? Let’s see: 110-72 = 38 dBSPL.
38 dBSPL means the noise would still theoretically be audible, because it’s still 18 dBSPL higher than the room noise level (20 dBSPL). Unless I lower the volume of the amplifier to lower the noise floor level. Is this calculation correct?
6. However, in practice, this shouldn’t be an issue. In fact, we haven’t yet considered the masking effect of human hearing:
during peaks (loud sounds) in music, we are less sensitive to quieter sounds, therefore, the noise floor of the recording seen earlier (38 dBSPL), should not be audible when the music plays loudly. Right?
And what if the music plays at lower levels? For example, at 50 dBFS?
In this case, the remaining DR of 72 dB, at medium listening volumes like 60 dBSPL, should give us more than enough headroom, because the noise will still be at 60-77 = -17 dBSPL, well below the threshold of the room noise floor. Right?
Am I missing something?
But nothing has caused me as many headaches as the concept of dynamic range, and I can’t seem to wrap my head around it by myself anymore. Having to also translate from English, there are still many points that aren’t clear to me.
I would like you to help me understand if my reasoning is correct and, if necessary, correct me on the bolded parts.
1. 116 dB is our best-case hearing dynamic range. Perhaps because the ear acts as a compressor of the dynamic range? Since the dynamic range of hearing is 140 dB (we can hear from 120/130 dBSPL down to -10 dBSPL) but this wide dynamic range cannot be perceived all at once. Is that correct?
2. 108 dB (18 bit) is the best-case scenario for music resolution. But, unless it’s computer-generated music, we must take into account the electronic noise from the recording microphone (16 dBSPL?), so 108-16 = 92 dB (15 bit). Is that correct?
3. The rule of thumb is that our audio devices should have a DR 10 dB higher than that of the music, so 108+10= 118 dB (19.6 bit).
4. The noise in my listening room is about 20 dBSPL, at best:
- But our ear is not a microphone, and since we perceive different frequencies at different levels, our threshold of audibility varies between 10 and -10 dBSPL, according to Fletcher-Munson curves, so some frequencies of this noise will be perceived at higher levels, and others at lower levels;
- However, shouldn't this is equally valid for the noise floor of a recording? Maybe the noise floor in a recording is made of the same frequency? So how can I calculate a difference in audibility between the noise floor of the listening room and that of the recording itself?
- Not knowing how to do it, I will consider it as 20 dBSPL, so 92-20 = 72 dB (12 bit).
If I want to consider peaks at 110 dB (classical music), could I achieve this with a DR of 72 dB? Let’s see: 110-72 = 38 dBSPL.
38 dBSPL means the noise would still theoretically be audible, because it’s still 18 dBSPL higher than the room noise level (20 dBSPL). Unless I lower the volume of the amplifier to lower the noise floor level. Is this calculation correct?
6. However, in practice, this shouldn’t be an issue. In fact, we haven’t yet considered the masking effect of human hearing:
during peaks (loud sounds) in music, we are less sensitive to quieter sounds, therefore, the noise floor of the recording seen earlier (38 dBSPL), should not be audible when the music plays loudly. Right?
And what if the music plays at lower levels? For example, at 50 dBFS?
In this case, the remaining DR of 72 dB, at medium listening volumes like 60 dBSPL, should give us more than enough headroom, because the noise will still be at 60-77 = -17 dBSPL, well below the threshold of the room noise floor. Right?
Am I missing something?