Aircraft sound systems

[Mike Diack]

Having just spent around 50 hours of my life in the last month on B777s, I continue to be astonished by how bloody awful the audio feed from the little personal AV system is. Is it just the $2 headphones they use, with their massive peak around 150Hz that makes them rattle or is the problem further back in the chain. I'm temped to wire a couple of mono 0.125" jacks up to a decent pair of cans and see if there is a difference. If this fails, electronics (in the form of a little amp and EQ) may help (this presupposes some knowledge of what lies on the other side of those two 1/8" holes on the seat arm). Anyone here got a day job at Boeing ?.
M

 

[Jason Lavoie]

Re: Aircraft sound systems

they're still making planes with those proprietary plugs?? it seems they've all been replaced with standard plugs here.
I'm pretty sure I've seen adapters for sale before. wish I could remember where.

that being said, good headphones do make a difference, but it's still not ideal because I think they adjust the tone controls to suit crappy headphones
the other part of the problem is that because of the background noise you're turning those little headphones way louder than you ever would sitting in the airport.

Jason

 

[kristianjohnsen]

Re: Aircraft sound systems

Having just spent around 50 hours of my life in the last month on B777s, I continue to be astonished by how bloody awful the audio feed from the little personal AV system is. Is it just the $2 headphones they use, with their massive peak around 150Hz that makes them rattle or is the problem further back in the chain. I'm temped to wire a couple of mono 0.125" jacks up to a decent pair of cans and see if there is a difference. If this fails, electronics (in the form of a little amp and EQ) may help (this presupposes some knowledge of what lies on the other side of those two 1/8" holes on the seat arm). Anyone here got a day job at Boeing ?.
M

Here's a mental experiment you might not like: Every part of the aircraft comes from the lowest bidder. Being sound people we can tell how crappy the audio system is. I wonder about the quality of the landing gear :evil:

Seriously, the combination of crappy aircraft headsets and the rest of the signal chain as well as the acoustic environment of the aircraft makes for a lot of rattly, boxy crappy audio. Hollywood movies are the worst as they have a really annoying hyped low end in the first place. Stuff like sitcoms and news casts are usually a lot better. I have said for a long time that the movie companies should remaster the movie audio for planes. The films are re-edited to make them family rated and fit into the 2-hour cycle of international flights anyways, so why not?

PS: You can buy the adaptors at certain airports and my last IEM earpieces even had them included

PPS: When I was a kid my dad told me about flying to the US and having the audio transmitted to the earsets via just hoses/tubes. No wires, no electrics, no stereo, no channel selection, no volume control. Just a big speaker in a box somewhere in the back of the plane with plastic tubes going out of it. Squeeze the tube and your earpiece goes quiet! I'd love to try out one of those systems to see check how it sounded.

 

[kristianjohnsen]

Re: Aircraft sound systems

they're still making planes with those proprietary plugs??

Some models of sommercial planes have a surprising long lifespan, although they are upgraded from time to time to cater for things like more legroom (slimmer seatbacks, etc) and entertainment systems. I think one reason for sticking with the funny headphones plug is that certain companies make you pay to rent a headset.

 

[John Roberts]

Re: Aircraft sound systems

Here's a mental experiment you might not like: Every part of the aircraft comes from the lowest bidder. Being sound people we can tell how crappy the audio system is. I wonder about the quality of the landing gear :evil:

Not to ruin your joke, but aircraft engineers are highly motivated to get reliability engineering and component certification right. Aircraft tend to fall out of the sky when important systems fail. IIRC Murphy's law cam from the aircraft industry wrt components that were poorly engineered and could be installed backwards.

Any competitive business will be motivated to manage input costs. I had my share of experiences with purchasing employees, motivated by rewards if they reduced parts cost, pushing inferior components on me to approve. It got so bad at one point I made purchasing bring in a couple thousand pots to do an actual production line test with them. Then the purchasing guy caused an ugly scene and started arguing with me in the factory, when the parts were crap and didn't work (like I predicted). The factory had to unsolder and replace all the pots with good ones so we could use the boards.

Seriously, the combination of crappy aircraft headsets and the rest of the signal chain as well as the acoustic environment of the aircraft makes for a lot of rattly, boxy crappy audio. Hollywood movies are the worst as they have a really annoying hyped low end in the first place. Stuff like sitcoms and news casts are usually a lot better. I have said for a long time that the movie companies should remaster the movie audio for planes. The films are re-edited to make them family rated and fit into the 2-hour cycle of international flights anyways, so why not?

PS: You can buy the adaptors at certain airports and my last IEM earpieces even had them included

PPS: When I was a kid my dad told me about flying to the US and having the audio transmitted to the earsets via just hoses/tubes. No wires, no electrics, no stereo, no channel selection, no volume control. Just a big speaker in a box somewhere in the back of the plane with plastic tubes going out of it. Squeeze the tube and your earpiece goes quiet! I'd love to try out one of those systems to see check how it sounded.

The simple hollow tube headphones worked adequately for the day, and were cheap as dirt.

I thought there were aircraft headphones you can buy (noise canceling), and adapters to plug into airplane audio. Check the airline flight magazines. That's where I'd try to sell them.

JR

 

[Caleb Dueck]

Re: Aircraft sound systems

I remember using the sound tube headphone system a few times while younger. Sounded OK considering what it cost.