Re: [LAD] Floating point processing and high dynamic range audio

On 2010.07.21. 20:05, Paul Davis wrote:
> On Wed, Jul 21, 2010 at 2:01 PM,<fons@email-addr-hidden> wrote:
>> On Wed, Jul 21, 2010 at 01:26:40PM -0400, Paul Davis wrote:
>>
>>> floating point -1.0 == minimum value of an integer sample == -inf dBFS
>>> floating point 1.0 == maximum value of an integer sample == 0dBFS
>>
>> ??? At least the first of these makes no sense at all,
>> and the second applies if the dB value indicates a digital
>> peak level. More accurately: 0dB digital peak corresponds
>> to a sample value of + or - 1.
>
> yeah, i got the first one wrong. mea culpa. but i think you need to
> avoid using "dB" in this context, and be clear about using dBFS.
> restated:
>
> floating point value of -1.0 == minimum value of an integer sample
> floating point value of 1.0 == maximum value of an integer sample
> floating point value of 0.0 == -inf dBFS
> floating point value of +/- 1.0 == 0 dBFS
>
>> An audio signal represents pressure variation as a function of
>> time. Multiplying it by two will give 2 times the pressure,
>> and 4 times the power. The subjective result is another matter.
>
> i was trying to be precise enough to include nonlinearities in the
> analog path. perhaps unnecessary.

Thanks! This starts to make some sense and helped a lot.
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Received on Thu Jul 22 00:15:03 2010