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The volume is too damn high on flights

blog.42floors.com

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Re: The volume is too damn high on flights

#171

The PA when heard over the headphones (when watching a movie, etc.) is even worse - I wouldn't be surprised if it was over 100dB. Sometimes a movie has quiet audio, or quiet moments requiring you to turn up the volume a lot. More than once I have been painfully ear-raped by the flight attendant PA system in my earphones for this reason. Just another instance of outrageously bad customer service in the airline industr…

Noise-Cancelling headphones with external inputs, by their principle of operation, already have to funnel everything through a DSP. So it would be easy to implement a compressor/limiter for the external input signal. Is this feature available on any of the commercially available headphones?

As an explanation: A compressor/limiter is a device in audio processing used for leveling (compressing) the dynamic range, by making quiet things louder, and making louder things quieter. In the extreme case, one can configure a threshold of (power, loudness, amplitude, depending on the operation of the devices) which cannot be exceeded. [All you sound engineers, please excuse the simplification...]

https://en.wikipedia.org/wiki/Dynamic_range_compression

Re: The volume is too damn high on flights

#172
post #161

Earlier quoted context omitted.

In my experience, the announcements are always in the top 95% of the channel's dynamic range. Setting the volume such that the announcements are at a reasonable level renders everything else way too quiet.

But, in my experience, the way that's implemented is that when there's an announcement, everyone's volume is temporarily overridden to 100%. Hence my solution: Set things up so your volume is always at 100%, and the inline volume control device is throttling that down to a comfortable level.

Mine too. I believe you're exactly right here. Volume seems to be attenuated from 100% at the armrest by the digital control, and overridden back to 100% when the PA is keyed. I've done exactly what you described and I stopped getting audibly assaulted on flights where I opted to listen to channel 9, or to watch a censored movie.

Re: The volume is too damn high on flights

#173

Earlier quoted context omitted.

Music is basically never going to sound good over a POTS because it's a low-bandwidth channel optimised for human voice: http://en.wikipedia.org/wiki/Voiceband It may also be a legacy system using old worn-out looping casette tapes for the music.

It's even worse if the sound is going through a digital (VOIP / cell phone) system. Most modern codecs for voice are using some form of Linear Predictive Coding[1] (e.g. ACELPC) which is basically modeling sound as a resonator at the bottom of a tube with a filter bank (sortof like your voice box). With voice, this is a reasonably good approximation, and the codecs are aggressively tuned to be efficient at that. But…

"Flapping plosive at the bottom of a long tube."

What an exceptionally colorful description of the effects of that type of codec! Well done.

I wonder if there are applications for psychoacoustic modeling approaches for safety/compulsory announcements. Can they be encoded in a different way before broadcast on the PA to take advantage of our perception of human speech? And possible a different codec still for users of headphones?

Or perhaps a quick, sharp attention tone before urgent broadcasts, but for non safety/compulsory announcements, a lower volume setting...

Re: The volume is too damn high on flights

#174
post #3

I've noticed this too. On my last few flights it has been so loud it caused physical discomfort (to me) and made my toddler cry.

It's been my assertion, as both a solo passenger and one traveling with a child, that crying babies and toddlers are the result of one of two things:

1) Kids need to be chewing something, or sucking on a nipple/bottle/straw to help facilitate inner-ear pressure changes. Most aren't, and those that can't say "my ears hurt" simply scream.

2) Kids who are tired (because they're kids or because their parents figured "I'll tire him out so he sleeps on the flight") and get startled by a scary loud voice saying things they don't understand. Like yours - probably a tuckered out toddler desperate to rest, no?

(Edited to avoid sounding like I was disagreeing with parent comment)

Re: The volume is too damn high on flights

#175
post #128

I could believe it. I just flew Spirit (never again, for reasons in addition to this) a couple of weeks ago, and they spent the last 20 minutes or so of the flight hawking some kind of credit card deal. Even wearing earplugs barely put a dent in the volume.

I've not experienced this at all, but I routinely fly American or United (or their international "alliance" partners). My next flight is on Southwest. I wonder how different that'll be - boarding procedures don't generally bug me (we're all going to the same place in a giant airborne metal tube), but crew behavior has the power to wreck the experience for me.

Re: The volume is too damn high on flights

#176

Earlier quoted context omitted.

Dude, I'm only 29 and I've flown in about 50 or 60 flights. I don't need to hear that I should put on my own oxygen mask before helping a toddler yet again . I get why they do it every flight, but I certainly don't need to pay attention.

Yeah, but do you pull out the airplane schematic to familiarize yourself with the layout of the airplane you're riding in? Serious question: Without looking it up on your travel itenerary, can you honestly tell me what make/model airplane you last flew on? I can, because I read the pamphlet, which gives me knowledge that could save my life, but if you don't want to live to see 30, that's your perogative...but it's th…

Not to argue with your point as a whole - that apathy that leads to risk to others is a bad thing - but...

Yeah, I've looked at the pamphlets on the hundreds and hundreds of flights I've been on. I've sat in the emergency row, first class, back galley, you name it on dozens of models of aircraft.

Within a few moments of taking my seat, I know where my nearest exit is, and I know how to open it in an emergency because nearly all commercial aircraft doors open the same way. I know from a quick reach-under that the vest is still there, and that they're designed to be of obvious function with their large handle for self-inflation and the tubes for manual inflation.

I don't need to be told to grab for an oxygen mask before it falls - I would posit that it's instinctual, even as a parent, so that I am better equipped to help my fellow passengers (or my kids if they're with me) and so that my action can set an example for those that don't know what to do. All the seats of all the planes I've been on in the past ten years or so have been able to be used as flotation devices.

I'm not saying that these things are common knowledge. "Noobs" should listen. But "veterans" shouldn't be assaulted with high volume, or assumed to be shirking their duties as fellow passengers if they respectfully mind their own business during the safety announcement.

Talk during the announcement? Shut the hell up, you're messing with the learning of someone else, and you're going to cause others to talk over it. Quietly play Bejeweled while wearing headphones during the announcement? I'll assume you've "been there" and "done that" often enough to not be a liability to the rest of us if something goes wrong.

Incidentally, when told about the exits by the flight attendant, do NOT ask "in the event of an unexpected landing event, am I authorized to escape via the twisted, burning, gaping hole in the aircraft?" They don't find that amusing.

Re: The volume is too damn high on flights

#178
post #128

I could believe it. I just flew Spirit (never again, for reasons in addition to this) a couple of weeks ago, and they spent the last 20 minutes or so of the flight hawking some kind of credit card deal. Even wearing earplugs barely put a dent in the volume.

I've not experienced this at all, but I routinely fly American or United (or their international "alliance" partners). My next flight is on Southwest. I wonder how different that'll be - boarding procedures don't generally bug me (we're all going to the same place in a giant airborne metal tube), but crew behavior has the power to wreck the experience for me.

I haven't seen it on any other airline either. I think it's only on the "discount" airlines, where you can get a slightly cheaper flight... as long as you buy your baggage check and check in in the right way and don't expect to actually eat or drink anything on board.

Re: The volume is too damn high on flights

#179
post #89
post #56

Few thoughts: > and opened the decibel meter on my iPhone These are notoriously inaccurate. To get accurate decibel readings, the mic must be calibrated to absolute known levels (something your App can't do). The App's are basically just comparing relative sounds (this sound is more prominent than this other one, and therefore must be louder... after establishing some relative baseline). Real decibel measuring equipm…

165 db LCpk is a good estimate for the muzzle blast 1 m in front of the barrel of a shotgun. However, outdoors, it's going to be closer to 140-150 measured at the shooter's head. There is a significant asymmetry in how the muzzle blast propagates.

1m in front of the barrel of a shotgun, I'd hearing loss is the least of your worries!

Re: The volume is too damn high on flights

#180
post #3

I've noticed this too. On my last few flights it has been so loud it caused physical discomfort (to me) and made my toddler cry.

It's been my assertion, as both a solo passenger and one traveling with a child, that crying babies and toddlers are the result of one of two things: 1) Kids need to be chewing something, or sucking on a nipple/bottle/straw to help facilitate inner-ear pressure changes. Most aren't, and those that can't say "my ears hurt" simply scream. 2) Kids who are tired (because they're kids or because their parents figured "I'l…

Great tips for flying with kids in general. I'm pretty confident that these particular instances were due to the announcements as things instantly went from happy to crying "it hurts! loud!" with hands over ears, then back to (relatively) happy once it was over.
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