Audacity Forum

Hi..first thing, sorry for my English:I'm Italian and there isn't an Italian Forum in here...so I'll do my best to express myself properly.
I've downloaded Audacity today and I've tried to converse some tapes in mp3. everything is ok but when,after all, I listen to my new mp3 files I discover that music and words are too quick! Strangely if I save the same project as .wav I haven't the same problem. What I have to do to save as mp3 having the right speed??
Thanks for your help.... and good night
Valeria

What happens if you Export As WAV, and then open up that wav file and Export As MP3?

That is not a perfect way to produce an MP3 file, but it is a good emergency method if it works. We are having troubles with MP3 export and we don't know why yet.

Ciao,

Koz

The usual reason is playing the exported MP3s in a flash-based player that can't cope with MP3s which have a sample rate that isn't a multiple of 11025:
http://audacityteam.org/wiki/index.php? ... s_too_fast

Please export the MP3 at 44100 Hz (set in the project rate dropdown bottom left of the Audacity screen). If that does not help, please confirm you are on Audacity 1.2.6 and what player you are playing the files in. I don't think it's relevant but the latest (v3.98) lame_enc.dll is here.


Gale

It seems there is a more general current problem with the recent v3.98 lame_enc.dll.
I can immediately reproduce the problem in Audacity 1.2.6 or 1.3.6 using v3.98 as
obtained about a week ago from Rarewares. This appears to be a very recent issue
though, because I did have a v3.98 obtained about 6 weeks ago from them which
did not have this problem.

Please use lame_enc.dll v3.97 from:
http://lame.buanzo.com.ar/

and you should have no problem if you export at 44100 Hz.

Sorry for the trouble experienced, but obviously this one is outside our
control.


Gale

Thanks...you' re very nice. I didn't expected so many answers!!
Trying to export as you explained I get the same result....

I'm running Audacity 1.2.6 and then I listen to my files with VLC

I've just tried to convert .wav file I've obtained with audacity using exact audio copy but it says it's impossible ...it doesn't recognize it.

I've already exported at 44100 Hz.... now I'll try with all your other suggestions

<<<and you should have no problem if you export at 44100 Hz.>>>

That's a problem, isn't it? Most of my serious captures are at 48000, the video sound standard. It's not a multiple of 11025. I checked.

[frowny face]

Koz

I've just tried using lame_enc.dll v3.97 from: http://lame.buanzo.com.ar/ but I get the same result....

Anyway, I'll try again....

...and sorry for my English!!!

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?

GOALLLLLLLLLLLLLLLLLLLLLLL

Exporting at 22050 Hz the speed is perfect!!! Thank s!!

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