Comment by daneel_w

A couple more:

    afconvert(1) - an audio file format converter, which includes Apple's superior AAC codec from the Core Audio framework

    diskutil(8) - tons of tools for fixed and removable storage

Examples:

    afconvert in.wav -o out.m4a -q 127 -s 2 -b 160000 -f m4af -d 'aac '

    mb=300; diskutil eraseVolume APFS myramdisk `hdiutil attach -nomount ram://$((mb*2048))`