You cannot create "true" discrete 5.1 from a stereo source.
The rear channels and center channel don't exist in the original recording. Software can only synthesize them using phase differences, EQ, and delays. For music, this often sounds hollow or weird. For movies/gaming, it can work well.
Netflix and Disney+ stream native 5.1, but your personal collection of local music (FLAC, WAV, MP3) does not. Users want to listen to their old Beatles or Pink Floyd albums through their new AV receivers in full surround. stereo to 51 audio converter software hot
You can have the best software in the world, but if your hardware is wrong, it will sound like a stereo echo chamber. You cannot create "true" discrete 5
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