A recording technique in which a sound or message is deliberately recorded backwards in a track that is meant to be played forwards.(noun)
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Use "backmasking" in a sentence
"April 4th, 2007 at 9: 31 pm its not an actual sumbliminal message as in a line or speech thats played in reverse as u guys that are saying "just sounds like jibberish" … its called backmasking … someone recording them talking or singing or rapping, and then adding it to the song backwards in a lower volume so its not heard wen played forwards … i should kno … ive done it a couple times in my music to jus to see wat it sounded like … and now for my opinion on the video … its totally fake … DJ Dangermouse chopped n screwed it from a couple of different verses from Jay-Z's songs … he even openly admitted it that Jay-Z had nothing to do with the backmasking of that time …"
"Hey, I hope most of you do realize that many of the so called backmasking is really what is called a phonetical reversal."
"But beyond unforgettable songs and legendary live shows, Led Zeppelin broadcast a powerful message to fans who were tuned in to their music at a particular frequency -- one far more subversive than the Satanic messages the band was accused of "backmasking" into "Stairway to Heaven": Bring the soul of the West and Islam together, it told us, and you can produce a musical force powerful enough to break through the barricade dividing the two civilizations."