Reducing HZ rate of audio?

I have a mp3 audio fl with a hz rate of 48000 hz, how can i reduce it to 441000 hz? -thanks!

Set the “Project Rate” (bottom left corner of the main Audacity window) to 44100 before you export. The “Project Rate” determines the sample rate of exported files.

Do you mind if I ask why? If everything goes well, you won’t hear a difference… CDs are 44.1kHz and DVDs are 48kHz. If you want to make an audio CD your CD burning software should automatically re-sample the audio.

Most of my MP3s are 44.1kHz, but I have a few audio files extracted from video. They are 48kHz I don’t have any reason to change them.

As you may know, MP3 is lossy compression and when you open it in Audacity (or any “normal” audio editor) it gets decompressed. Then if you re-export it as MP3 you are going through another generation of lossy compression. You may not hear any quality loss, and sometimes it’s unavoidable, but it’s something you should be aware of.

Reducing HZ rate of audio?

This is the sample rate. During analog-to-digital conversion, there are 48,000 (or 44,100, etc.) samples per second. There are also 48,000 samples per second in the audio file, and 48,000 samples per second are converted to analog by the digital-to-analog converter.

With uncompressed files, the file size is directly related to files size.

With MP3s and other compressed formats we are usually more interested in the bit rate (kbps) which is the number of bits per second in the compressed file. The bit rate is a rough guide to quality… The lower the bit rate, the smaller the file, which means more data was thrown-away.

“Hz” relates to frequency, so it also relates to the audio content. The “traditional” human hearing range is from 20Hz (very low bass) to 20kHz (very high pitch). (The sample rate has to be at least twice the frequency of the audio content.)