# Why do some airlines use dual plugs for their headphones? **URL:** \ **Category:** Factual Questions\ **Created:** [August 21, 2001, 5:47pm UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380 "2001-08-21T17:47:42Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![chutwig](https://avatars.discourse-cdn.com/v4/letter/c/e56c9b/32.png) [@chutwig](https://boards.straightdope.com/u/chutwig)\ **Post date:** [August 21, 2001, 5:47pm UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/1 "2001-08-21T17:47:42Z")
I never quite figured out if there was an actual reason or if it was just to keep me from using my headphones that don’t suck. I know Lufthansa are guilty of this; mercifully, British Airways were not. However, in 45 minutes I’m about to pop onto a US Airways flight over to London, and I’ll be disappointed if I am once again rightly denied my single stereo plug. ---
**Author:** ![Jimpy](https://avatars.discourse-cdn.com/v4/letter/j/c68b51/32.png) [@Jimpy](https://boards.straightdope.com/u/Jimpy)\ **Post date:** [August 21, 2001, 6:09pm UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/2 "2001-08-21T18:09:14Z")
Let me guess, the airlines that have dual plugs rent headphones, right? ---
**Author:** ![bughunter](https://avatars.discourse-cdn.com/v4/letter/b/aeb1de/32.png) [@bughunter](https://boards.straightdope.com/u/bughunter)\ **Post date:** [August 21, 2001, 6:17pm UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/3 "2001-08-21T18:17:53Z")
Well, the only dual plugs I’ve seen are acoustic couplings, but then I haven’t flown overseas in decades. The transducers are actually in the armrest, and the “cords” are actually tubes to carry the sound to the earpieces. To provide seperate stereo channels, they need two tubes. ---
**Author:** ![Syzygy](https://avatars.discourse-cdn.com/v4/letter/s/bc79bd/32.png) [@Syzygy](https://boards.straightdope.com/u/Syzygy)\ **Post date:** [August 21, 2001, 6:23pm UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/4 "2001-08-21T18:23:19Z")
I’m with **Jimpy** - they make the female end with two mono jacks rather than a stereo jack so you have to rent **their** headphones. I usually steal the headphones afterwards. Screw 'em. ---
**Author:** ![hawthorne](https://avatars.discourse-cdn.com/v4/letter/h/c89c15/32.png) [@hawthorne](https://boards.straightdope.com/u/hawthorne)\ **Post date:** [August 21, 2001, 6:30pm UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/5 "2001-08-21T18:30:34Z")
I’d lean towards the opposite conclusion to Scott and Jimpy. I’d guess it is to discourage stealing (because their sets are useless elsewhere), rather to encourage renting. FWIW, where I’m from, the headsets are always free, but use the same two plug system. ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [August 21, 2001, 6:41pm UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/6 "2001-08-21T18:41:24Z")
AIRPLANE STEREO AUDIO JACK ADAPTER $ 2.99 Item# 141 0210 Our handy airplane audio jack adapter allows you to use any headphones with a stereo mini plug on board and in flight. Hand their headphones back to them. Yo u deserve the best audio possible! ·Compact and lightweight [http://www.cyberguys.com](http://www.cyberguys.com) ---
**Author:** ![pldennison](https://avatars.discourse-cdn.com/v4/letter/p/9fc29f/32.png) [@pldennison](https://boards.straightdope.com/u/pldennison)\ **Post date:** [August 21, 2001, 6:58pm UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/7 "2001-08-21T18:58:02Z")
> [@](#): > > \*Originally posted by bughunter \* > \*\*Well, the only dual plugs I’ve seen are acoustic couplings, but then I haven’t flown overseas in decades. > > The transducers are actually in the armrest, and the “cords” are actually tubes to carry the sound to the earpieces. To provide seperate stereo channels, they need two tubes. \*\* This is correct. When I flew to Maui in January, I didn’t watch the movie, and listened to my own music on a Discman, so I didn’t rent the headphones. At one point, when I had my own earphones off, I could have sworn I heard a song from “The Simpsons” playing. I then realized that it was coming out of my armrest, and playing with the volume and channel dials confirmed it. ---
**Author:** ![Syzygy](https://avatars.discourse-cdn.com/v4/letter/s/bc79bd/32.png) [@Syzygy](https://boards.straightdope.com/u/Syzygy)\ **Post date:** [August 21, 2001, 7:10pm UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/8 "2001-08-21T19:10:31Z")
Yeah, I remember the old acoustic coupling system. I haven’t seen that for quite a while, though. Maybe that’s because I’m usually on domestic flights. When I flew on American Airlines recently, the jacks in the seats were two standard mono headphone jacks, spaced about 5/8" apart. The male end (on the phones) had two mono prongs. I wonder if it has to do with the airline, or the plane? On the return trip, same airline, different plane: Standard stereo headphone jack - my personal phones worked just fine. Oh, and AA did charge $4 for the phones on the flight. So I kept them. They were worth about $4, anyway. 😃 ---
**Author:** ![Sultan\_Kinkari](https://avatars.discourse-cdn.com/v4/letter/s/7bcc69/32.png) [@Sultan\_Kinkari](https://boards.straightdope.com/u/Sultan_Kinkari)\ **Post date:** [August 21, 2001, 7:23pm UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/9 "2001-08-21T19:23:38Z")
British Airways uses the dual audio jack(one large pin, one small pin) so they can provide better quality headphones to their passengers without the fear that they will stick them in their carry on before they leave the plane. Dual jack headphones cannot be used in a standard audio jack, and even if you were to break off the smaller pin, you would only get sound out of one ear. ---
**Author:** ![navtechie](https://avatars.discourse-cdn.com/v4/letter/n/b19c9b/32.png) [@navtechie](https://boards.straightdope.com/u/navtechie)\ **Post date:** [August 21, 2001, 8:18pm UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/10 "2001-08-21T20:18:29Z")
I recently have flown to the Netherlands twice this summer on United Airlines in business class, where we had the option of the free single jack headphones or renting the special BOSE headphones that negate most of the ‘white’ noise of the plane. I opted for the BOSE and slept like a baby, they really do work. But off of my tangent, On United, and KLM/Northworst they have single jack headphones. ---
**Author:** ![Gozu\_Tashoya](https://avatars.discourse-cdn.com/v4/letter/g/7993a0/32.png) [@Gozu\_Tashoya](https://boards.straightdope.com/u/Gozu_Tashoya)\ **Post date:** [August 21, 2001, 11:23pm UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/11 "2001-08-21T23:23:39Z")
**navtechie** , how was the sound quality on the Bose headphones? I mean, on the one hand it _is_ Bose, but on the other, I read that sound cancellation headphones tend to have rather muted sound fidelity. Of course this was before the Bose ones came out, and I’m wondering if they were able to come up w/ white noise killing headphones that still sound _good_. \ ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [August 22, 2001, 12:12am UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/12 "2001-08-22T00:12:44Z")
I fly all the time, and have the following observations: American, TWA, and Delta have the acoustic two-prong ones on Domestic US flights. British Air and Air France have two-prong electronic ones. American Transatlantic flights in Biz Class have the Bose Acoustic Wave headphones, which IMO work fantastic. And on all the flights I have been on in 8 years, coach, business and first class, domestic and international, I have never once seen headphones for rent. They have always been passed out for free. Which airlines charge you for headphones? ---
**Author:** ![Swede\_Hollow](https://avatars.discourse-cdn.com/v4/letter/s/3bc359/32.png) [@Swede\_Hollow](https://boards.straightdope.com/u/Swede_Hollow)\ **Post date:** [August 22, 2001, 1:07am UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/13 "2001-08-22T01:07:42Z")
On my last flight to California on a Northwest Airlines widebody there were two audio jacks, but one gave stereo sound while the other was silent (at least with my own headphones). When the crew where offering the cheap NWA headphones they announced that the 'phones were yours to keep. On the trip back the plane only had one headphone jack and there was nobody going around offering the headphones (it was a late flight so maybe they figured everyone would be trying to sleep). ---
**Author:** ![audient](https://avatars.discourse-cdn.com/v4/letter/a/ad7895/32.png) [@audient](https://boards.straightdope.com/u/audient)\ **Post date:** [August 22, 2001, 2:48am UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/14 "2001-08-22T02:48:35Z")
cool games to play with acoustically coupled headphones- I remember not being able to get the volume set just right. It was either too loud or too soft. I found that I could get the volume level in between the 2 settings by turning it up loud and then _tying a knot_ in the rubber cord (tube). Tighten it to turn down. I was proud of myself when I figure that one out. try _that_ with an electrical cable. ---
**Author:** ![Lawmill](https://avatars.discourse-cdn.com/v4/letter/l/ecc23a/32.png) [@Lawmill](https://boards.straightdope.com/u/Lawmill)\ **Post date:** [August 22, 2001, 3:09am UTC](https://boards.straightdope.com/t/why-do-some-airlines-use-dual-plugs-for-their-headphones/77380/15 "2001-08-22T03:09:15Z")
> [@](#): > > navtechie, how was the sound quality on the Bose headphones? I mean, on the one hand it is Bose, but on the other, I read that sound cancellation headphones tend to have rather muted sound fidelity. Of course this was before the Bose ones came out, and I’m wondering if they were able to come up w/ white noise killing headphones that still sound good. I bought Aiwa HP-CN5 noise-canceling headphones before a trip to Italy. I think they retail for around $90. The sound is fine, nothing spectacular. The sound quality seems a little better than the $10 Sony headphones that I usually use with my CD player.