[airo]

It was a question that came to me today...
 
Can anyone explain to me why airplanes have those two seperate mono outputs instead of just one stereo?
The only reason I can think of why they exist is to have a market of airplane adapters
 
Does it have to do with interferance or some other kind of process?
I mean, there must be a reason but why? It can't be that difficult to have a stereo output right?

 

[insidedrive]

Thats a good observation, I have never thought of it. However the audio coming out of the jack must be horrendous.

 

[CJG888]

It all depends on the age of the cabin. Increasingly, modern aircraft (e.g. Boeing 777) are being fitted with standard stereo jacks. In Business, you will tend to get a standard stereo jack together with a power jack for any active noise cancellation circuitry in the cans.

In the past, I presume the "dual mono" approach had something to do with cabin crew wanting to sell or hire out "special" headphones to passengers...

Incidentally, I recently had the dubious privilege of flying in an old 757 (China Southern) which still had the old mono "stethoscope" headsets. Remember those? I thought those went out with the 727!

 

[squallkiercosa]

Just a guess but possibly to stop people stealing the headphones, If it had a standard plug they would lose a lot of them.
 
AA offer standard plugs but they give you awful earphones. So the question will be which option gives the passenger a better experience: awful standard headphones or relatively good headphones with a different plug? 

 

[KamijoIsMyHero]

Cuz of priorities and probably to save money

 

[billybob_jcv]

Just a guess but possibly to stop people stealing the headphones, If it had a standard plug they would lose a lot of them.

 

Exactly. In the old days, the headphones were free, and you were supposed to leave them in the seat at the end of the flight. They made them with a different plug so you wouldn't take them with you. Now they sell them to you, so it's cheaper for them to get them with a standard plug.

I agree on the old "stethoscope" style - those SUCKED. Just a hollow plastic tube stuck in your ears!

I figure that eventually, the airlines will put coin slots on the bathroom doors, and use of the cabin air supply will also be an additional charge. "For your breathing convenience, we accept credit cards only. Cash is no longer accepted onboard the aircraft. Please use the in-seat system to order your breathable air prior to the aircraft reaching an altitude of 30,000 feet or loss of consciousnesses and brain death may occur. We know you have many choices for your airlines and we appreciate your choosing Stack'em & Pack'em Airlines."

 

[squallkiercosa]

Quote:

I figure that eventually, the airlines will put coin slots on the bathroom doors, and use of the cabin air supply will also be an additional charge. "For your breathing convenience, we accept credit cards only. Cash is no longer accepted onboard the aircraft. Please use the in-seat system to order your breathable air prior to the aircraft reaching an altitude of 30,000 feet or loss of consciousnesses and brain death may occur. We know you have many choices for your airlines and we appreciate your choosing Stack'em & Pack'em Airlines."

 
I think you guys have no idea how expensive an airplane can be. To put few things in perspective:
 
Airbus 380 unit cost: US$389.9 million[3] (approx. €300 million or GB£252 million)
Boeing 747 unit cost: $352.0 million
 
Considering that each one of them carry roughly about 600 passengers with an average cost of 700$ it will have to make ~1000 trips in order to pay itself, leaving aside fuel (which is ridiculously expensive) crew, maintenance, taxes and so on. Low cost lines uses old airplanes in order to travel for significant less amount of money. 
 
Not because you think it should be cheaper, it has to be. 

 

[airo]

I think you guys have no idea how expensive an airplane can be. To put few things in perspective:

Airbus 380 unit cost: US$389.9 million[3] (approx. €300 million or GB£252 million)
Boeing 747 unit cost: $352.0 million

Considering that each one of them carry roughly about 600 passengers with an average cost of 700$ it will have to make ~1000 trips in order to pay itself, leaving aside fuel (which is ridiculously expensive) crew, maintenance, taxes and so on. Low cost lines uses old airplanes in order to travel for significant less amount of money. 

Not because you think it should be cheaper, it has to be. 

Yeah I get that airplanes and maintainance costs can be expensive but are mono jacks more expensive than stereo? I mean you'd have to include 2 jacks instead of one. When you can just manufacture one stereo you'd be making two for mono, and beside, it's not like the outputs need maintainance or anything, its just a one time thing

 

[squallkiercosa]

Quote:

Yeah I get that airplanes and maintainance costs can be expensive but are mono jacks more expensive than stereo? I mean you'd have to include 2 jacks instead of one. When you can just manufacture one stereo you'd be making two for mono, and beside, it's not like the outputs need maintainance or anything, its just a one time thing

Airo, you have not yet understand the issue. The jacks are not the problem, the headphones are. Replacing headphones in every flight might be really expensive, I'm telling you because I took a pair once in AA like 15 years ago and pretty sure I wasn't the only one who did it. Now, they don't have to worry about losing money because of people stealing them.
 
Make your life easier: get an adapter, most of the active noise cancelling headphones come with one and use your own. 

 

[billybob_jcv]

Sure, airplanes are expensive - and airlines are expensive to run. Yet the airlines still manage to run specials to go from LA to NY for $200. I actually think air travel is too cheap and far too many discount fares are handed out in order to fill airplane seats. Domestic flights on airlines like American & United have become a complete joke due to the lack of space, uncomfortable seats and crappy service. Both Southwest & Virgin America are far, far better airlines - and they pale in comparison to JAL and some of the other top-tier international carriers. There are HUGE amounts of waste in the airline industry. Everyone has their hand out - the various federal, state & local government agencies, the equipment manufacturers, the airlines, the unions, the travel industry - everyone has a team of lawyers and the true source of revenue for the entire ponzi scheme is the poor consumer that gets packed into a 17" wide seat.

Virgin America A320:
Coach Seat Width: 19.7 inches
Coach Seat Pitch: 32.0 inches
Coach Entertainment: Personal Sat TV & Movies

American Airlines 737-800:
Coach Seat Width: 17.2 inches
Coach Seat Pitch: 31.0 inches
Coach Entertainment: Shared Movie

http://www.seatguru.com/charts/shorthaul_economy.php

 

[airo]

Airo, you have not yet understand the issue. The jacks are not the problem, the headphones are. Replacing headphones in every flight might be really expensive, I'm telling you because I took a pair once in AA like 15 years ago and pretty sure I wasn't the only one who did it. Now, they don't have to worry about losing money because of people stealing them.

Make your life easier: get an adapter, most of the active noise cancelling headphones come with one and use your own. 

I'm not complaining in any kind of way, I have like 5 adapters at home. I'm just a curious guy trying to bring up a topic here.

Anyways I get what you mean now. Yeah replacing and people stealing headphones may be a problem.

I've never used airline headphones except once and I totally forgot their connector. Do they really have those two mono connector? I can't recall anything except for their awful sq.

 

[billybob_jcv]

Most newer airplanes now have a standard mini-jack. The problem is that the older airplanes have been sold down to the lower tier airlines, so if you are flying a local commuter airline on an old 737-200 or an older MD-80, you will still see the dual mono jacks.

 

[jjinh]

Quote:

I'm not complaining in any kind of way, I have like 5 adapters at home. I'm just a curious guy trying to bring up a topic here.

Anyways I get what you mean now. Yeah replacing and people stealing headphones may be a problem.

I've never used airline headphones except once and I totally forgot their connector. Do they really have those two mono connector? I can't recall anything except for their awful sq.

 
Yeah, just bring an adapter. Even the noise-cancelling ones I've had in-flight (usually some sort of Audio-Technica NC headphones) were terrible.
 
Some airlines give out free headphones for you to keep. Last time I flew Virgin domestically in Australia (admittedly quite a while ago) they had bins full of earbuds at all the gates for you to take as you walk onto the plane.
 
Anyway what do airlines do with old headphones? Remove the pads, clean them, put on new pads and re-use them - might be cheaper to just throw them out and get new ones...

 

[DerbDad]

Airo, you have not yet understand the issue. The jacks are not the problem, the headphones are. Replacing headphones in every flight might be really expensive, I'm telling you because I took a pair once in AA like 15 years ago and pretty sure I wasn't the only one who did it. Now, they don't have to worry about losing money because of people stealing them.

Just an FYI...I flew with Delta this weekend. The flight attendants were selling earbuds, with the dual-mono adaptor included, for $2. That was in coach. I assume they were free in First Class since I saw a number of earbuds in unopened packages on the seats as I was getting off of the plane. The 767 had a stereo jack in the armrest so the adaptor was not needed.

Even at $2 a pair, I'll bet they are making a profit and therefore no longer worry about losing money by passengers keeping the headphones.

 

[White Lotus]

Hey guys, hot tip:

Bring a volume controller.

This is the Westone one that I use.

 

 
 
Set the aeroplane headset amp to full, then limit your volume using this little guy. Only a few bucks, and you'll have perfect impedance matching. No more hiss! More accurate volume control.

I never fly without one.