I am using macOS Catalina 10.15.7.
I am using Audacity 2.4.2.
As I am recording, whether it be LPs or voice, a message appears on the bottom of the screen stating:
Recording Disk space remaining for recording: 13 hours and 21 minutes
This time lessens as I continue to record.
When saving each project, I save them to an external hard drive.
I am concerned that soon there’ll be no recording time left and recording will fail.
Obviously hoping to avoid this.
I save them to an external hard drive.
How? Do you export the work as WAV (Microsoft) 16-bit sound files? That’s the safest method. WAV sound files are “perfect quality,” uncompressed and will open and play on all three computer platforms.
You can Save Audacity Projects which will also save the environment and edit settings along with the work, but those are brittle, subject to failure, and they will only open in Audacity.
After you save the work, close Audacity and it will free all the space being used for edit, capture, and production.
Disk space remaining for recording: 13 hours and 21 minutes
That’s not a lot of free space. That’s what this looks like on my machine.
Go into your system and read how much drive space you have and how much is unused.
Go > Computer > Macintosh HD > File > Get Info.
Sometimes Macs can accumulate “stuff” just by being awake. Apple (upper left) > Restart… Pay attention if your Mac takes forever to shut down or gives you a spinning daisy as it goes. I used to regularly get one of the office managers out of trouble because he would open apps and tools and just forget about them. His machine would slowly strangle.
Do you use Time Machine backups or do you do manual backups? Both?
Uncompressed “CD quality” files (16-bit, 44.1kHz, 2-channel stereo) requires about 10MB per minute.
Audacity projects (and Audacity’s temporary storage) use 32-bit floating-point, so double that. Plus add the space required for your exported file.
…If you know there are 8 bits in a byte it’s easy to calculate file size (for uncompressed files):
Bytes per second = (Bit Depth/8) x Sample Rate (Hz) x Number of channels (Or with the sample rate in kHz we get kilobytes per second.)
For compressed files we can use the bitrate: kpbs is kilo_bits_ per second, so we can divide by 8 to get kilo_bytes_ per second. (If there is embedded artwork it takes up more space, additional to the bitrate calculation.)