[Audio Empire]

On Tue, 4 Sep 2012 16:36:09 -0700, Scott wrote
(in article ):

On Sep 4, 10:39=A0am, "Arny Krueger" wrote:
"Scott" wrote in message
...

[quoted text deleted -- deb]

The problem with all of this is considering the room tone to be a
noise floor the same way you have noise floors in the equipment
itself. The noise floor in real life is 0 in that all the "noise" in
real life is actually signal not noise. I want to hear the sound of
the room. that isn't noise that is the sound that transports me as a
listener to that space. The true dynamic range of real life is about
120 dB depending on one's thresholds of pain.

Back in the real world, the primary sources of room tone in most
contemporary live recordings is HVAC noise and/or other forms of atmospheric
or structure-borne noise from the environment.

Every time I do a spectral analysis of room tone from one of my recordings I
see the LF spikes from the HVAC air movers and hiss from the turbulent air
in and around the ducts and vents.

Everybody who wants to suffer the economic slings and arrows of building a
120 dB dynamic range recording system in order to produce 60 dB dynamic
range recordings of HVAC and traffic noise can be my guest! As things
stand, I'm usually producing recordings of them with 30 or so dB dynamic
range, and seems to produce little concern on the part of the paying
customers. A nicely done fade in and out at the beginning and end of the
song, and all seems well.

I believe the question posed was what is the dynamic range of the real
world for us as listeners. If you don't like the sound of the rooms
you are recording in I suggest finding better rooms. But that sound,
whether or not you approve of it is part of the real world and is not
noise in the same sense as you have noise in the gear itself. so if
one is actually interested in capturing everything one can hear one
does need a dynamic range of at least 120 dB. At least. If one is
interested in getting it without gross distortion one needs
substantially more headroom.

Exactly. The dynamic range that I was talking about is on the top end of the
loudness scale anyway... the noise floor being a case of "it is what it is."
But Mr. Kruger brings up a good point. The recordable dynamic range, that is
to say, the actual difference between the noise floor (whether that floor be
technology limited as with analog tape or environmentally limited like HVAC
systems and traffic outside of the venue or people noises) is generally far
short of what the technological dynamic range is for modern digital
recording. The truth is that we must set the levels high-enough for the
tripple "p" sounds to be captured in spite of the ambient noise level of the
venue yet at the same time, be able to capture the tripple "f" crescendi of
the orchestra during instrumental climaxes without distortion.

The main advantage of 24/32-bit PCM recording or DSD recording is that you
can record wide dynamic range material without the danger of overmodulating
and distortion. You just record at a lower average value. There are dynamic
limitations on both ends of the loudness scale, and having enough bits to
comfortably record everything without resorting to gain-riding is a real
luxury. Take it from somebody who spent a lot of years recording in 16-bit,
first on video tape, using a Sony F1 and a Betamax recorder, and later using
an Otari R-DAT recorder. 24-bit was a real help when it became generally
available to modest location recordists like myself.