The first DJs to use two turntables may well have been a soundsystem in Jamaica, although some disco DJs in NY could take the crown (late 60s either way). One among them being the first Grandmaster, Flowers.
Flowers was probably the first DJ to play park jams, and he influenced not only Herc but a whole raft of upcoming DJs including Disco King Mario.
I've been researching Kool Herc and the beginnings of Hip Hop for a while, and I wanted to share a few notes...

Herc never played Jamaican tunes. He wasn't proud to be Jamaican at the time, it wasn't cool in NY. He tried his absolute hardest not to be Jamaican in the '70s.
Herc was DJing before 1973, he wasn't successful before then, but that party on August 11th wasn't the start of Kool Herc and it wasn't the birth night of Hip Hop. Hip Hop as we know it is younger than that.
Grandmaster Flash was the inventor of the slipmat. Hands down I can't find any other person even mentioned in a breath with him. He referred to them as felts, and bemoaned that he didn't have his two with him in the club. NO ONE ELSE HAD THEM.
Bambaataa is often mentioned in the same breath as Herc and Flash, with the innovations they brought Bam wasn't in the same echelon.

He almost never came up as an innovator, and we'd do best to remember Mario, Flowers, Pete Jones, DJ Hollywood all before Bam.
Before we get to 1975 I'm not sure you could say Hip Hop was in existence, and before 77 there's no way you'd suggest it was bigger than the five boroughs (generous inclusion of Staten Island too).
This thread is just a long way of saying I made a video for the first time in half a decade;
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