Kiss's Gene Simmons saw the band play a gig at the now defunct Starwood club in Hollywood, financed and produced about 15 tracks, and then presented them to Casablanca (their record label at the time) who rejected them. He then had them play a showcase at SIR in New York for Bill Aucoin (Kiss's manager) who also thought they had no potential. Van Halen then came back to Hollywood, played the tapes for Warner Brothers, and the rest is history. The basics on the Simmon's demo were cut at Village Recorder in Los Angeles and the guitar solos and vocals at Electric Ladyland in New York.
Here's the little bit that I heard on the song that's different.
1) The delayed reverb on the guitar that became a Van Halen signature is missing.
2) David Lee Roth's delivery of the vocal doesn't swing as much.
3) The feel of the solo/bridge part is a lot different.
4) There's a hard ending as compared to a fade. (Actually, I got this one wrong.)
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