[bigshot]

  Still, if 24bits are so necessary then someone can feel free to post an example of music or movie material that would need more than what 16bits + noise shaping can give.

 
I've been looking for that example for years. Haven't found one yet. Greenears was looking for one too, and hasn't been able to find one that demonstrates his theories in real world playback of music yet. He's been working very hard at it too.

 

[cjl]

 
No that's not what I'm saying really.  Even if you set the peaks (or crests as you call them) to 50 dB SPL and compress (raise) the bases to 45 dB SPL so that you have an average (or RMS) of 5 dB dynamic range, you can still easily hear way more bits than either 5dB or 20 dB (50 - 30) implies.  This is the mixing up of THD+N and dynamic range and quantization that is often repeated - that is my point.
 
But it's really not worth arguing over any further.  I think my illustrated numbers will allow objective readers to realize that it is not that simple, because clearly the equation used this way does not extend to all values.  I think I've expressed my point sufficiently.

Ahh, but if it's properly dithered, you won't have any quantization noise. You'll have noise, yes, but that's entirely different. If the noise generated by your speakers is significantly lower than the noise floor of your room, you will not hear any increase in noise (unless it's noise of a specific and clearly audible character). If your room has a noise floor of 30dB, and you want a noise level on your recording of 20dB (so it's 10dB below room noise), that still allows for peaks of 116dB on a 16 bit recording (and realistically, a bit more than that if you use proper, noise-shaped dither).

 

[Greenears]

   
I've been looking for that example for years. Haven't found one yet. Greenears was looking for one too, and hasn't been able to find one that demonstrates his theories in real world playback of music yet. He's been working very hard at it too.

I've finished testing for the time being, and I've written my final summary of my testing.  I'm ready to post it.  I don't think you will like the surprising conclusion. 
 
But nevertheless, I want to be very clear for our dear readership  They are not "my theories".  I didn't create them. Sorry, not that smart. At most I have tried to understand some of them, and I don't think I fully understand all aspects some pieces of it are opaque. 
 
This paper I found recently I think summarizes many of the theories pretty well and lists an extensive set of citations for further reading.  It is by no means the only paper on this but I found it fairly representative of what I had been told in the 90s and what seems to be coming from the DAC manufacturers today.
 
http://www.zainea.com/Dynamic%20range.htm
 
All I tried to do was see if I could personally hear anything beyond 16 bit.  That's all.

 

[bigshot]

  All I tried to do was see if I could personally hear anything beyond 16 bit.  That's all.

 
And you tried REALLY hard to hear it!

 

[Greenears]

   
And you tried REALLY hard to hear it!

Right you are. No half measures here!

 

[RRod]

 
I've finished testing for the time being, and I've written my final summary of my testing.  I'm ready to post it.  I don't think you will like the surprising conclusion. 
 
But nevertheless, I want to be very clear for our dear readership  They are not "my theories".  I didn't create them. Sorry, not that smart. At most I have tried to understand some of them, and I don't think I fully understand all aspects some pieces of it are opaque. 
 
This paper I found recently I think summarizes many of the theories pretty well and lists an extensive set of citations for further reading.  It is by no means the only paper on this but I found it fairly representative of what I had been told in the 90s and what seems to be coming from the DAC manufacturers today.
 
http://www.zainea.com/Dynamic%20range.htm
 
All I tried to do was see if I could personally hear anything beyond 16 bit.  That's all.

 
What is this music he listens to that requires you hear both 129dbSPL musical content and 3dbSPL white noise?

 

[bigshot]

No human being would be able to hear 3dB after a 129dB peak. The ears would need a few minutes to adjust. I seriously doubt that anyone could hear 3dB in a normal living room anyway.
 
Stuff like this is absurd because it's the same sort of repeated worst case scenarios stacked on top of each other that audiophiles love to do. Alice in Wonderland thinking. Compared to theory, the real world must be seem like a very messy and noisy place to people who think like this.

 

[RRod]

  No human being would be able to hear 3dB after a 129dB peak. The ears would need a few minutes to adjust. I seriously doubt that anyone could hear 3dB in a normal living room anyway.
 
Stuff like this is absurd because it's the same sort of repeated worst case scenarios stacked on top of each other that audiophiles love to do. Alice in Wonderland thinking. Compared to theory, the real world must be seem like a very messy and noisy place to people who think like this.

 
The article he linked says that the 3dB (avg) white noise was audible in a typical noise-level room due to audibility of a particular band above the room noise, which I'm willing to believe, and it didn't precede the white noise by any other content. It pieces together two numbers: some numbers on the loudest concert sounds which end up about 130dB, and the lowest perceptible white noise (listened with 2s on-off cycles). I'd be pretty unsurprised if people had to adjust the pot when listening to a file that gradually shifts from 3dB white noise up to 130dB music. Perhaps I'll put this example together.

 

[limpidglitch]

 
I've finished testing for the time being, and I've written my final summary of my testing.  I'm ready to post it.  I don't think you will like the surprising conclusion. 
 
But nevertheless, I want to be very clear for our dear readership  They are not "my theories".  I didn't create them. Sorry, not that smart. At most I have tried to understand some of them, and I don't think I fully understand all aspects some pieces of it are opaque. 
 
This paper I found recently I think summarizes many of the theories pretty well and lists an extensive set of citations for further reading.  It is by no means the only paper on this but I found it fairly representative of what I had been told in the 90s and what seems to be coming from the DAC manufacturers today.
 
http://www.zainea.com/Dynamic%20range.htm
 
All I tried to do was see if I could personally hear anything beyond 16 bit.  That's all.

 
I seem to miss the place where he explains why 129dB peak values actually are appropriate, live concert levels or not, that's loud.
Why didn't he ask the subjects he had hunting for white noise decide what appropriate peak values are? Give them the remote control and tell them to go as high as they feel comfortable.

 

[bigshot]

   
The article he linked says that the 3dB (avg) white noise was audible in a typical noise-level room due to audibility of a particular band above the room noise, which I'm willing to believe, and it didn't precede the white noise by any other content. It pieces together two numbers: some numbers on the loudest concert sounds which end up about 130dB, and the lowest perceptible white noise (listened with 2s on-off cycles).

Yes, but when you are listening to music on a stereo in a living room, none of that applies. It's worst cases stacked up on top of each other without any context.

 

[RRod]

 
Yes, but when you are listening to music on a stereo in a living room, none of that applies. It's worst cases stacked up on top of each other without any context.

 
It's still nice to know the weapons that might be lobbed at you ^_^

 

[Greenears]

I would not go too far overboard trying to parse all the details.  Just realize he is referencing a large number of papers (50) and I think comes to the conventional conclusion that somewhere around 18-20 bits is the limit of human hearing.  And as I've said I've heard the same conclusion before, I am not proposing this as a big surprise or the best explanation. 

 

[bigshot]

People can't hear over 50dB at any given time. If they are going to hear a wider dynamic, they need time for their ears to adjust. 16 bit is overkill for listening to music.

 

[analogsurviver]

   
I seem to miss the place where he explains why 129dB peak values actually are appropriate, live concert levels or not, that's loud.
Why didn't he ask the subjects he had hunting for white noise decide what appropriate peak values are? Give them the remote control and tell them to go as high as they feel comfortable.

129 dB peak values during live concerts are uncommon, but are not that rare.
 
I remember recording a jazz quartet - and setting the recording level best I could during the rehearsal. They said "NO" to the question whether they intend to play any louder during the concert.
 
But in one piece, during the ending of the song, the drummer went crazy - all out. If I were recording to anything else but to what I did ( cassette deck + HighCom II noise reduction ), the recording would have ended like toast.
+11 ref 0 dB   !!!!
The recorder and metal tape are actually capable of taking these levels in the bass - where it is usually needed. Absolutely no audible distortion/compression - while any digital recorder would go into hard clipping, resulting in an unusable recording.
 
Such high levels occur ONLY during live performances. I also remember once asking the percussionist of the symphonic orchestra to play during his rehearsal really loud for me to set the recording level when he was alone in the hall. BOTH the security guy and director of the orchestra came rushing to see what the hell is breaking loose - yet due to my experience I set the maximum recording level solo percussion reached at - 4 dB for the evening recording.
 
As it was a DSD recording, it did not matter for the peak in the finale of the concert to reach +2 dB ( DSD recorders "survive" up to + 3dB without catastrophic consequences ) - and NOBODY complained, all were thrilled by it.
 
Asking people to listen to the white noise at these levels outside some musical reference is simply asking too much. Scientific - yes, practical - NO.

 

[RRod]

Yeah but how quietly did that jazz quartet play? Probably not 3dB SPL