[LAD] Floating point processing and high dynamic range audio

[JohnLM]

  Hey, fellow devs!
I'm a newcomer to this mailing list and I'm sure this has been discussed 
here at some point, but I'll ask anyway.

I'm a bit better on programming side than on audio-tech side so...
  - Does all floating point formats mandate valid values in [-1.0, 1.0] 
range?
  - How does floating point (and perhaps fixed point/integer) values 
relate to dB notation?
  - If I muliply float by 2.0, do I get twice the sound pressure or 
twice the sound intensity, or something else?

Well as for internal processing. If I mostly use integer formats for 
inputs, it doesn't appear I gain anything from "normalizing" them (scale 
to [-1.0, 1.0]) during internal processing. I just output integer part 
directly to integer formats (adjusted for different bit resolutions when 
necessary), and normalize only when saving to float format. What do you 
think?

Proprietary formats such as AC3 and DTS market themselves as high 
dynamic range. Do they use values over 0dBFS or do they just have higher 
bit precision than "standard" formats?

Thanks!

-- JohnLM