The Logic Off Topic list

marc lindahl <marc@...> wrote:

>> From: Dennis Gunn <dennisg@...>
>>
>> Once about 9 years ago on the DAW I remember writing about how the
>> digital wave form for a sine wave up around say 19.k looks like a
>> broken spiral staircase and how I find it hard to believe that any
>> amount of filtering is going to turn that into a clean sine wave.  A
>> lot of peaple called me ignorant for being decieved by the look of
>> data but Nothing I have seen or heard since has ever convinced me I
>> was wrong.
>
>You're not hearing the data - you hear the data after it's been timed and
>output through a D/A converter, which includes a reconstruction filter.  To
>compare apples to apples you need to hook an oscilloscope up to that analog
>output and compare the two.  You'll see that the digital sinewave looks the
>same.
>
>There have also been studies done showing that different looking waveforms
>(due to the relative phase of thier harmonics) sound the same - so don't be
>deceived by how a waveform looks.  It's useful information, to be sure, like
>when editing, but it's not perfectly correlated to the sound.

This observation is not relevant to a sine wave as any change in appearance
at the *audio*  output outside of a strict shift in phase, can only be
distortion.

S.