[ntp:questions] Accuracy of audio tones via VOIP

Robert Scott no-one at notreal.invalid
Wed Jul 10 02:27:57 UTC 2013

On Tue, 9 Jul 2013 23:07:40 GMT, Harlan Stenn <stenn at ntp.org> wrote:

>John Hasler writes:
>> Landline long-distance usually goes over packet-switched networks as
>> well these days.  Unless your call to NIST is local you probably
>> aren't hearing the tones they sent.
>I have heard (and I haven't checked in to this) that a good number of
>local calls are converted to digital pretty quickly, too.  It would be
>interesting to find out and do a study from a variety of locations.

There is nothing inherently wrong with converting to digital and back
again.  As long as the clocking signals on the encode and decode end
are running at the same frequency the frequency of the reproduced
audio will be exactly the same as the original.  The only problem is
when those clocks are not synchronized, as in Skype.

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