A couple of things:
Flash DID NOT invent sampling like/as we know it today. With 2 Turntables and a mixer all you could do was loop a section over and over or simply blend in another record
it should be noted that there were Disco djs doing this technique already
MODERN SAMPLING with a digital sampler was about making a collage of sounds into one piece of music. This is how Marley Marl and people that followed were taking snares from 1 record and combining them with hi-hats from another, to form a new drum groove and then even adding a bassline from another record . You can't do this on turntables
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The scratch didn't come out of Flash' Quick mix theory concept, it already existed in the Disco scene from when they were queuing up the record but it wasn't something meant to be heard as music
Tyrone the Mixologist (Black Spades/Disco King Mario associate) was the one who first did it intentionally
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The last point, you can loop breaks w/o doing the quick mix style if you know how to needle drop on time. This technique is harder to do than double copy back spinning. Grandmixer DXT talks about it here
The 2 cats that Flash was scared of were 2 of the best needle droppers:
Grand Wizard Theordore
Flash on Theordore:
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