Was thinking Motorollin extracted just his voice from a tune...
Well you *can* do it that way by filtering out all the other frequencies, but it's usually quite messy as there's inevitably overlap between the frequencies in the voice and those in other instruments. That means you either have to leave some of the backing in, or carve out frequencies with the ranges used in the voice, which alters the sound of the vocals. Doomy's original version was vocals only, so I just recorded it.
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moto