24Bit Save in New version 3.3

Saving a 24 Bit recorded file in the new version 3.3 is the same size a s 16 Bit. Previous version 3.2.5 the size for 24 bit is twice the size 16 Bit which is what you would expect

That can happen with compressed files but not with uncompressed files.

If you make a 24-bit FLAC from a 16-bit file, FLAC is “smart” and it will be the same size as a 16-bit FLAC. (In Audacity you have to turn-off dither to get the same-exact size because dither adds to the low-order byte would otherwise be zero when you up-sample from 16-bits.)

Lossy compression (MP3) doesn’t care what you start with, except with VBR you get a bigger file (higher bitrate) when the sound is more “complex” and “harder to compress”.

There are 8-bits in a byte so uncompressed files can be calculated in bytes per second as:
Sample in Hz x (bit depth / 8) x number of channels

You can multiply bytes-per-second by 8 to get the bitrate in bits per second.

“CD quality” WAV files are 176.4kB per second for a bitrate of 1411kpbs.

Ignoring embedded artwork, etc. It’s 50% bigger. :wink: A 32-bit file at the same sample rate would be twice as big.

I’m confused. Not trying to convert a 24 bit file from a 16 bit file After recording a song to completion, than select File/export audio -in window save as type - select Flac from drop down box than set bit depth to 24 bits. This saves a flac file where the audio properties show file size and bit depth of 24 Bits. With 3.3 release the bit depth says 24 bits, but the file size is now the same as saving the file as a 16 bit flac file, That doesn’t seem to make any sense, as it should near double the size. This works correctly in release 3.25.

Your soundcard (or other device) PROBABLY has a 16-bit analog-to-digital converter. It can be hard to tell and often the specs are misleading because any old sound card can “support” high-resolution. recording and playback. The drivers take care of any conversions without bothering to tell you. By default, Audacity works at 32-bit floating-point so when you record or open a file, it’s up-scaled.

…When I saw your first post I saved a WAV file as 16- and 24-bits and the results were as-expected.

Try this:
Make some small change… Maybe run Amplify at -1dB. The calculations and rounding should fill-in all of those “extra” bits & bytes that are now zero and the FLAC should be bigger.

…Saving as MP3 and re-opening it will also change all of the samples/bytes so that should also give you a bigger 24-bit FLAC.

MediaInfoOnline can check your FLACs and tell you if they are 16 or 24-bits. It’s just checking the format. It doesn’t look at what’s inside the file.

This worked properly in Version 3.25 which I have gone back to. My sound card is a Focusrite Scarlet 2i2 which supports sample rates 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz, 192kHz. Just for info, I rerecorded the same song in Acoustica saving as 24bits and got basically the same file size as Audacity 3.25. I switched from Acoustica to Audacity many years ago because of the much simpler operation . I made no changes to my system before installing version 3.3

I took a source that I know is a legitimate 24-bit audio source and exported it using Audacity 3.3.1 at 16 and 24 bits in both FLAC and WAV. Here are the resulting file sizes:

  • WAV 24-bit: 48.1 MiB
  • WAV 16-bit: 32.1 MiB
  • FLAC 24-bit: 38.9 MiB
  • FLAC 16-bit: 22.9 MiB

I am using the Linux version. I presume you are using Windows?
If you’re able to share a file that is exhibiting this behavior, perhaps someone might be able to reproduce the issue.

Also, what is your setting for “Default Sample Format” in “Audio Settings”? Ideally you want that set to 32-bit float.

No. 24 bit is 3 bytes per sample. 16 bit is 2 bytes per sample, so a 24 bit WAV file would be expected to be approximately 3/2 = 1.5 times the size of a 16 bit WAV file (assuming they are both the same length and both mono or both stereo).

I set the Effect/Amplify to -.1 and that appeared to solve the problem. Strange

Not really “strange” and not really a “problem” unless you want the 0.1dB change and the smaller file.

Or you could lower the volume by 0.1dB, export as 16-bit WAV, re-import and when then your 16 and 24-bit files would have the same size again!

Just to make everything clear, the data I am trying to save as flac is the 32bit float recorded recorded at 44100 hz The audio is generated by Cakewalk using various plugins. Played through the Focusrite Scarlett 2 sound device, thru a Mackie mixer which allows for mixing in a Roland Sound module or microphones (if wanted) , back to the Focusrite device and than into the PC using Win 11 into Audacity.

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