Video players

[Len Ovens]

On Wed, June 5, 2013 2:34 am, edmund wrote:
> On Wed, 05 Jun 2013 01:21:19 +0200
> Hartmut Noack <zettberlin at linuxuse.de> wrote:
>
>> Am 04.06.2013 02:43, schrieb Len Ovens:
>> >
>> > On Mon, June 3, 2013 8:02 am, edmund wrote:
>> >
>> >> What are you calling "uncommon" sample rates? Ubuntu Studio is for
>> >> multi media and in my case High res audio. Here we use 96 kHz and
>> >> 192 kHz sample rates.
>> Of course I have recorded in these samplerates also and in very few
>> cases it really makes a difference. Most notably to me was, that Alsa
>> Modular Synths sounds quite different at 96KHz.

That is possible... but, the audio in and out of a computer even at 96Khz
is still limited to just over 20kHz. The differences you are hearing may
be as a result of the math at higher frequencies affecting what ends up in
the 20-20kHz passband.
>>
>> >> VLC player,
>>
>> Is made to play the audio, that is relevant out there, where people
>> listen to music that is mixed and mastered and that is: 48KHz Video,
>> 44.1KHz Audio and that is it.
The bluray standard is 192/24, you don't get anything extra for your
money,  but it is the standard. Much of the audio on such music started
out as 48/16... (If it was on tape originally then 48/13 or less)

>> > seems to play these formats too but it doesn't!
>> >> When I play a 80 kHz sine it is audible

Shouldn't be, but then really there is no reason to play an 80k sine
through a computer because there are no known sound interfaces able to
reproduce signals of that frequency anyway. The analogue part of the chain
makes sure of that.

> No I mean playing a 80 kHz sine (with a 192kHz sample rate)
> I made a number of sines with audacity and played them with VLC among
> other players, VLC  produces ghost sounds with sine waves above a
> certain frequency.
>
> So paying music with VLC in that format makes you hear things you never
> heard before, great! Pity that the difference is fake and distortion
> rather then more music information.

That would be whatever does the resample or down/upsample. However, there
is no (and shouldn't be anyway) program material (even bluray 192 sample
rate stuff) that has 80khz content anyway. Any of the mics one can buy
start to roll of around 18hz (even condenser mics). So any signals above
that are artificially created. Buy some analogue test equipment and test
it for yourself. See what the highest frequency is that you can import and
export with your sound card. There is an audible difference, but it is not
in audio at 80khz.

Many audio programs use poor quality resampling BTW. VLC would depend on
it's libs.

This is something to consider. There are a lot of video players, but they
depend on only a few codec libs. We should break down our choices based on
the underlying libs I think.




-- 
Len Ovens
www.OvenWerks.net