Valeria wrote:Can you explain me, in simple words (if possible, because I fear it's a complicated thing) what's the tecnical difference in using a different frequence? I mean 44100 Hz or the other ones? which things does it change?
I'm glad you got the exported MP3 at the correct length/speed.
Digital sound works by taking "samples" of what in real life is a continuous audio stream. How many samples it takes per second is the frequency in Hz, so in the case of 44100 Hz, there are 44100 samples of audio per second. Any given sample rate can faithfully capture frequencies of approaching half that rate, so 44100 Hz can faithfully capture frequencies up to 20000 Hz or a bit more, which is the highest frequency humans can hear.
So the lower the sample rate, the lower are the frequencies that can be captured. If you exported an MP3 at 8000 Hz, it could not contain frequencies above 4000 Hz, so it would sound very dull because it had been robbed of its higher frequencies.
Koz, I think the audible loss from exporting a 44100 Hz MP3 instead of a 48000 Hz MP3 would be far less than the loss from exporting as MP3 instead of WAV. In any case even the 48000 Hz MP3 would remove some of the highest frequencies because that's what the algorithm does. For example you'll see that an MP3 exported at 44100 Hz of a file that has 20000 Hz frequencies in it will not actually have any higher frequencies than about 16000 - 18000 Hz.
Gale
