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Marian Perera
11-11-2013, 04:53 AM
Odd question, but I've been searching a bit on the Internet and found nothing helpful.

I have a character who needs to be heard over a distance of half a mile. If I weren't living in a city I would go out with a friend, measure half a mile and yell, but as it stands this is my best resource.

Also, would it make a difference if there are cliffs on either side of my character? Maybe the echo effect will help.

Thanks for any help, people!

Kylabelle
11-11-2013, 05:25 AM
Lots of variables in this. Yes, the cliffs make a difference as would the surrounding vegetation and even the weather.

As well, some people have astounding vocal capacity whereas others do not.

A half mile is a fur piece o' distance, there. And I have no idea what specifics would need to be in place for a bellow to be heard at such a remove. Dry air, not foggy, and certainly not rainy. No snow on the ground. No stands of trees or hills between the shouter and the one(s) hearing the shout. As well, you would potentially have echoes to contend with, if you use the cliffs. I'm not sure if that's important or not but it would make a difference in intelligibility of any content shouted and also any sense of direction!

Not sure how precise this factual accuracy needs to be, for your story, either. (Meaning, I suspect you could fudge some of this without any but the most knowledgeable reader noticing.)

Make sure your character has a deep chest! and it would help if he or she is a large person too. (Think of the proverbial "fat lady sings" in the opera. There's a reason so many opera singers are hefty people!) You could also set it up that the person has a loud voice in general, so it isn't too odd seeming that the shout is heard so far away.

I hope this helps a little bit.

Hmm. I am thinking too of yodelers~! That tradition, I do believe, originated because shepherds in the mountains needed to signal to each other. They would probably have no trouble being heard across a half mile! Try googling yodeling accoustics.

(can you tell I'm fascinated with this? :D )

King Neptune
11-11-2013, 05:36 AM
It is very dependent on atmospheric conditions and surface condition. Another consideration is the tonal quality of the voice to be heard and whether that would be interfered with by ambiant sound. In winter on ice I have heard conversations that were about a half mile away, and the people were not yelling; although they may have been speaking loudly. If the speaker has a clear voice, then it could easily be understood a half mile away.

check this out:
http://www.sengpielaudio.com/calculator-distance.htm
and
http://www.nonoise.org/library/sndbasic/sndbasic.htm#5
The seconf one have your answer directly.

I searched "sound dissipation distance decibel" and the results appear to be useful.

Kylabelle
11-11-2013, 05:45 AM
It is very dependent on atmospheric conditions and surface condition. Another consideration is the tonal quality of the voice to be heard and whether that would be interfered with by ambiant sound. In winter on ice I have heard conversations that were about a half mile away, and the people were not yelling; although they may have been speaking loudly. If the speaker has a clear voice, then it could easily be understood a half mile away.

check this out:
http://www.sengpielaudio.com/calculator-distance.htm
and
http://www.nonoise.org/library/sndbasic/sndbasic.htm#5
The seconf one have your answer directly.

I searched "sound dissipation distance decibel" and the results appear to be useful.

Welp. There ya go! :)

wendymarlowe
11-11-2013, 05:46 AM
Needs to be heard, or needs to be understood? I've done about 1/3 km before (through the woods during K9 search & rescue practice, clear day, on a local "mountain" but not particularly high altitude) and at that distance you can't make out words much. We always were supposed to yell "BO" because that was the easiest sound to make carry and also be distinguishable from various nature noises. I don't know that you could get 1/2 mile unless the canyon really helped it along.

That said, canyon walls really *could* help - and it's your book, so as long as it's plausible, you can go for it :-)

Helix
11-11-2013, 05:53 AM
Hmm. I am thinking too of yodelers~! That tradition, I do believe, originated because shepherds in the mountains needed to signal to each other. They would probably have no trouble being heard across a half mile! Try googling yodeling accoustics.

And don't forget the people of Gomera in the Canary Islands who use a whistle language to communicate across valleys and canyons (http://en.wikipedia.org/wiki/Silbo_Gomero_language).

King Neptune
11-11-2013, 06:02 AM
A little more research to satisfy my curiosity tells me that a clear, loud voice that started as 100 db, or so, would quite audible a half mile away. If the weather were cold, clear, and still, then it would be easier, becaue the air would be denser. The initial level is quite believable; in fact the loudest human yell measured was 124 db.

Kylabelle
11-11-2013, 06:08 AM
And don't forget the people of Gomera in the Canary Islands who use a whistle language to communicate across valleys and canyons (http://en.wikipedia.org/wiki/Silbo_Gomero_language).

"Don't forget" sez Helix. Never heard of this! but it is utterly fascinating to me. I love how the earlier cultures had these bodily technologies that did so very much. Singing your way (as in "songlines"), navigating oceans with songs (the Polynesians did this I believe), and now whistling!

Way cool.

Sorry for the lil derail there. :D

Marian Perera
11-11-2013, 06:20 AM
And don't forget the people of Gomera in the Canary Islands who use a whistle language to communicate across valleys and canyons (http://en.wikipedia.org/wiki/Silbo_Gomero_language).

This gave me a idea for the next manuscript, which will have people actually in the mountains and canyons. Thank you! (Plus, it was just fascinating information to have regardless)

Marian Perera
11-11-2013, 06:22 AM
A little more research to satisfy my curiosity tells me that a clear, loud voice that started as 100 db, or so, would quite audible a half mile away.

Hoorayyyyyyyyyyyyyyyyyyy! (imagine my voice tailing off into silence near the end as my shout dwindles in volume)

This forum is always so helpful with my work. :) Thanks muchly, everyone.

Siri Kirpal
11-11-2013, 07:34 AM
Sat Nam! (Literally "Truth Name"--a Sikh greeting)

One last tidbit: Male voices are usually louder than females due to the larger lung capacity, but high pitched female singers can be heard further than low pitched ones.

Blessings,

Siri Kirpal

thothguard51
11-11-2013, 08:07 AM
If there is a lake, sound carries easily over water...

Marian Perera
11-11-2013, 08:16 AM
If there is a lake, sound carries easily over water...

There's actually a narrow inlet with cliffs on either sides. Character is in the inlet.

thothguard51
11-11-2013, 08:21 AM
Waves crashing on shore or against cliffs could drown out a person's voice. It would have to be a very calm day...

King Neptune
11-11-2013, 04:59 PM
Hoorayyyyyyyyyyyyyyyyyyy! (imagine my voice tailing off into silence near the end as my shout dwindles in volume)

This forum is always so helpful with my work. :) Thanks muchly, everyone.

I thought it was tailing off because a breeze kicked up and blew it away.

Bushrat
11-14-2013, 12:16 AM
Totally depends on the conditions. Without motor noises, wind, rain, snow, rustling leaves or crashing waves to drown out the sound, you can easily hear shouting from half a mile away.

There isn't much noise pollution where I live, and when weather conditions are completely calm, I can often hear our neighbour's dog bark--and that's over a distance of 2 1/2 miles as the crow flies! But that's only under ideal sound-carrying conditions.