Just Noticeable Differences and bit-depth 16 vs 24

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There are numerous discussions about whether 16 bit is audibly
different from 24 bit. Meyer and Moran suggest it isnt[1] but this
paper has come in for a lot of criticism. I got to thinking thusly, 24
bits gives you a theoretical 144db (I think) of dynamic range and thus
allows a tremendous power of discrimination between levels so for
instance take

110000000000000000000001
and
110000000000000000000010

could anyone human tell the difference ? and would the difference be
subjectively different from...

1100000000000001
and
1100000000000010

can existing audio kit amp/speakers even render the difference
between

110000000000000000000001
and
110000000000000000000010

What in terms of the 65,536 levels is the just noticeable difference ,
ditto for the 16M levels for 24 bit ?
The JND is variously reported as being around 0.1 to 0.4db, how finely
does 16 or 24 bit audio render minimal
differences ?

Just Curious


1. "Audibility of a CD-Standard A/D/A Loop Inserted into High-
Resolution Audio Playback". E. Brad Meyer and David R. Moran. JAES
55(9) September 2007

[Arny Krueger]

> wrote in message
ps.com...

Conclusions of the subject paper (see fotnote 1):

"Claims both published and anecdotal are regularly made for audibly superior
sound quality for two-channel audio encoded with longer word lengths and/or
at higher sampling rates than the 16-bit/44.1-kHz CD standard. The authors
report on a series of double-blind tests comparing the analog output of
high-resolution players playing high-resolution recordings with the same
signal passed through a 16-bit/44.1-kHz "bottleneck." The tests were
conducted for over a year using different systems and a variety of subjects.
The systems included expensive professional monitors and one high-end system
with electrostatic loudspeakers and expensive components and cables. The
subjects included professional recording engineers, students in a university
recording program, and dedicated audiophiles. The test results show that the
CD-quality A/D/A loop was undetectable at normal-to-loud listening levels,
by any of the subjects, on any of the playback systems. The noise of the
CD-quality loop was audible only at very elevated levels."



> There are numerous discussions about whether 16 bit is audibly
> different from 24 bit. Meyer and Moran suggest it isnt[1] but this
> paper has come in for a lot of criticism. I got to thinking thusly, 24
> bits gives you a theoretical 144db (I think) of dynamic range and thus
> allows a tremendous power of discrimination between levels so for
> instance take
>
> 110000000000000000000001
> and
> 110000000000000000000010
>
> could anyone human tell the difference ? and would the difference be
> subjectively different from...
>
> 1100000000000001
> and
> 1100000000000010
>
> can existing audio kit amp/speakers even render the difference
> between
>
> 110000000000000000000001
> and
> 110000000000000000000010
>
> What in terms of the 65,536 levels is the just noticeable difference ,
> ditto for the 16M levels for 24 bit ?

JNDs are as small as 0.3 dB, depending on frequency and program material.



> The JND is variously reported as being around 0.1 to 0.4db, how finely
> does 16 or 24 bit audio render minimal
> differences ?

> 1. "Audibility of a CD-Standard A/D/A Loop Inserted into High-
> Resolution Audio Playback". E. Brad Meyer and David R. Moran. JAES
> 55(9) September 2007

More information:

http://www.bostonaudiosociety.org/explanation.htm