Problem changing 32bit 48kHz wav file to 24bit

Audacity Help Forum
1

Hi
I’m trying to change 18 mono tracks from 32bit 48kHz to 24bit 48kHz in Audacity by exporting tracks selecting signed 24 bit PCM. When I open exported file in audacity again it says file is still 32bit. What am I doing wrong?

2

any audio imported into Audacity is converted into 32-bit.
Look at MediaInfo of the audio file to see its actual specifications … MediaInfo - Wikipedia
MediaInfoOnline - MediaInfo in your browser

3

Thanks Trebor,

I’m going to double check that when i get home later, but it was the client who alerted me to the issue, not sure what they opened my file with. They suggested i should check my soundcard settings - using a Scarlett 2i4, but nothing on the dials amd switches on the soundcard itself seemed to indicate being able to switcg between bit rates.

4

Hi Trebor,

I downloaded mediainfo and the information it gives me is this…
First Audio Stream: 1 152 kb/s 48.0 kHz, 24 bits, 1 channel, PCM (Little / Signed)

However, a program like VLC still says it reads as 32 bits.

Is my client wrong, or am I not understanding something here? Sorry, I’m not very clued up on this!

Thank you
Dan

5

Yeah, it looks like you can’t trust VLC! I got the same thing, but when I tried an 8-bit file it showed correctly. (I didn’t try 16-bit file.)

Here’s another check -
There are 8-bits in a byte, so File Size = Playing Time in Seconds x (Bit Depth/8) x Sample Rate x Number of channels.

That’s only valid with uncompressed files and any embedded album art will add to file size and foul-up the calculation.

Or, the bitrate (kilobits per second) = 24 x 48kHz x 1 = 1152kbps.

6

Hi DVDdoug,

thanks for that. Before I get back to my client, perhaps I should copy/paste his response, in case you see something there that I’m missing? Thank you for your help thus far! Much appreciated!

Client: Everything else is fine, but the spectrum above 22k is lost, which should be related to incorrect sound card settings. You can check if the sound card setting is 48000Hz 24bit, and then ensure that the settings before recording are the same as the settings for exporting the file. (Note: both the sound card and the recording software need to be set to 48000Hz 24bit to meet this requirement, and the parameters for exporting the file need to be consistent.)

7

The bit depth (24-bits) and sample rate (48kHz) are unrelated parameters.

A higher bit depth gives you more amplitude resolution. A higher sample rate allows higher frequencies in your audio.

8

Hi Everyone,

Thank you everyone who responded. I massively appreciate your help. I like to think of myself as pretty savvy at fixing problems, but ultimately this came down to me being an idiot and just being unable to find my advanced microphone settings on Windows 10. Fuck. Once I changed those to 48kHz, spectrogram was picking up all frequencies 24k and beyond. I agree with you all about why on earth the client needs those frequencies in the first place (the job is the creation of an AI voice, I believe) but what the client wants, I’ll try to make sure they get. Beggars… choosers…

Again, thank you for your excellent explanations and help.
Dan

9

This topic was automatically closed after 30 days. New replies are no longer allowed.