# Sound (moving faster than the speed of)

**URL:** <https://boards.straightdope.com/t/sound-moving-faster-than-the-speed-of/133275>\
**Category:** Cecil's Columns/Staff Reports\
**Created:** [October 21, 2002, 6:55pm UTC](https://boards.straightdope.com/t/sound-moving-faster-than-the-speed-of/133275 "2002-10-21T18:55:38Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![mattcolville](https://avatars.discourse-cdn.com/v4/letter/m/90db22/32.png) [@mattcolville](https://boards.straightdope.com/u/mattcolville)\
**Post date:** [October 21, 2002, 6:55pm UTC](https://boards.straightdope.com/t/sound-moving-faster-than-the-speed-of/133275/1 "2002-10-21T18:55:38Z")

</div>

This is comment on Cecil’s [column.](http://www.straightdope.com/classics/a1_116.html)

Ok, here’s what I want to know…

I drive my convertable at mach 1.1. Sound from my rear speakers is carried away from me and I don’t hear it, right? Cause I’m going faster than the air can propogate it.

Ok, so let’s say it’s 1:00pm. I, driving mach 1.1, blast someone saying the word “One!” from my stereo. I keep driving.

Then, one minute later, I blast someone saying the word “Two!” from the speakers. One minute later. . .“Three!” One minute later, I stop.

Would would I hear?

Since, at 1:01pm, I had out distanced the sound of the “One!” and then made the “Two!” sound, wouldn’t the “Two!” arrive before the “One!” Ditto the “Three!”

Also, technically, since at each _instant_ I was outdistancing the sound of my speakers, wouldn’t I hear _whatever_ I had been listening to _backwards?_ as each sound was spit out of my speakers _after_ and therefore _ahead_ of the earlier sound?

---

<div class="post-metadata">

**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\
**Post date:** [October 23, 2002, 8:54pm UTC](https://boards.straightdope.com/t/sound-moving-faster-than-the-speed-of/133275/2 "2002-10-23T20:54:03Z")

</div>

In an idealized case, I think that you’re actually right on this. In any practical situation, though, you’re going to have enough other noise that you won’t be able to distinguish the radio at all.

---

<div class="post-metadata">

**Author:** ![CurtC](https://avatars.discourse-cdn.com/v4/letter/c/ce73a5/32.png) [@CurtC](https://boards.straightdope.com/u/CurtC)\
**Post date:** [October 23, 2002, 9:11pm UTC](https://boards.straightdope.com/t/sound-moving-faster-than-the-speed-of/133275/3 "2002-10-23T21:11:00Z")

</div>

You’d hear the sound backwards, but only after you’ve slowed down for the waves to catch up to you. Now just a few technical details to be solved, and a whole generation of kids with only CD players can hear The Beatles say “turn me on dead man.”