I did a little test with different builds posted here in the forum and my AMD Ryzen 5 3600X under Windows 11.
The file used, is a almost 2 hours long DJ set, of electronic music.
The fastest build was flac-1.4.1-win64-znver3 (Case).
Codec : PCM (WAV)
Duration : 57:21:749
Sample rate: 48000 Hz
Channels : 2
Bits per sample: 16
Igor Pavlov's timer64 have been used to measure the time.
timer64.exe flac -8p
flac-1.4.1-win64-znver3 (Case)
Global Time = 53.220
wrote 425812103 bytes, ratio=0,644
flac-1.4.1-x64-znver2-GCC1220 (john33)
Global Time = 53.621
wrote 425812103 bytes, ratio=0,644
flac-1.4.1-win64-gcc12 (Case)
Global Time = 56.626
wrote 425812106 bytes, ratio=0,644
FLAC-1.4.1_Win64_GCC122 (NetRanger)
Global Time = 59.990
wrote 425812106 bytes, ratio=0,644
flac-1.4.1-x64-AVX2 (john33)
Global Time = 73.045
wrote 425812100 bytes, ratio=0,644
flac-1.4.1-x64-AVX2-clang1500
Global Time = 78.772
wrote 425812103 bytes, ratio=0,644
FLAC-1.4.1_Win64_Intel 19.2 (rarewares)
Global Time = 79.738
wrote 425812100 bytes, ratio=0,644
FLAC-1.4.1_Win64_CLANG15 (NetRanger)
Global Time = 100.662
wrote 425812106 bytes, ratio=0,644