Alternative solution to "Change Tempo" and "Sliding Time Scale" for a higher quality output.

Hi!

I’m using Audacity 2.3.3 on Windows 64-bit.

I’m managing an mp3 audio, these are the informations:

Codec: MPEG Audio Layer 3(0x55) - Decoder FFmpeg interno(mp3float)
Sampling rate:: 48000
Bitrate: 0 ->16 bit/Sampling
Channels: 1 ->2 Channels
Bitrate: 128 kbps

It regards a speech, just an audio with somebody who is talking.

I need to reduce the speed of talking, keeping the pitch.

I’ve tried both “change Tempo” and “Sliding Time” under the Effects menu, setting a negative percentage value.
For the “Change Tempo” effect I’ve also checked the option for a higher quality.

The result is ok. It works as expected.

But the final voice of the audio is a bit “robotic” and less natural respect the original one.

I’m asking if exist a plugin or another tool or technique which is able to give a better result, closer to the original audio quality.

Thanks a lot.

I’m asking if exist a plugin or another tool or technique which is able to give a better result.

Not that I know of. Effect > Change Speed is the tool with the least damage to the sound. It changes both. The other two, pitch and tempo have to tear the sound apart and try to put it back together in a new order. The combination of those two tools and a compressed format such as MP3 is usually a bad marriage. MP3 gets its small, convenient files by leaving out some of the show sounds. It’s clever about it and nobody notices the damage—until you try to do production with the file.

Never do production in MP3.

Koz

Ensure that you also test with that option turned off. Sometimes the sound can be better with “high quality” turned off (it depends on the audio).