Lasers in the eye - Serious injury, Please Read

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Re: Lasers in the eye - Serious injury, Please Read

Postby gyre » Wed Nov 23, 2011 10:57 am

Why is excessive voiume a sacred cow?


These are my speakers, though mine are the pa version and look different.

Image
Image

Having artillery doesn't automatically make you a fool.
I've been involved with a number of concerts and studios.
I'm not unfamiliar with audio.

Why does anyone want volume beyond a rational point?
High power and very high bass are no special accomplishment now.
It's easy.


By the way, the french stopped some high decibel bass experiments when the technicians behind lead and concrete were found to be suffering internal bleeding.
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Re: Lasers in the eye - Serious injury, Please Read

Postby BBadger » Thu Nov 24, 2011 3:24 pm

Well, there are other explanations for high volume too: the high volume music can damage your cells and cause your body to release endorphins. So you get a, uh, "raver's high" or something.
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Re: Lasers in the eye - Serious injury, Please Read

Postby lemur » Thu Nov 24, 2011 3:45 pm

dangerous volume can injure more people than any laser.

roving "art" cars with highly directional high volume sound can be very dangerous out on the playa..
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Re: Lasers in the eye - Serious injury, Please Read

Postby gyre » Thu Nov 24, 2011 5:29 pm

This gets complex really quickly, but hearing is both psychological (interpreted or interpolated) and physical.

Noise (sound you don't want to listen to) does more damage than the same sound when it is welcome.

Harsh, non-harmonic sound is more damaging.
Examples in music include cheap amplifiers or overdriven amps, as well as all inharmonic sound.
NVH has actually been coined to refer to this issue = noise/ vibration/ harshness.
NVH is more important than volume.

The theory is that we don't hear some frequencies as well at lower volumes, so this is why people turn up volume.
http://en.wikipedia.org/wiki/Equal-loudness_curve

Whether true or not, we have a craving for accurate sound.
Physics being what they are, most home speakers can't produce lower bass, and distort when producing what bass they do produce.
Worse, most music is filtered for lower bass.
Digital sound is also worst at the lower frequencies.

I found when I moved to my better speakers, that i was satisfied with the bass I didn't know I had been missing.
Perhaps more important, larger cone surface reduces distortion dramatically.
(I had actually asked about this issue in class years ago, as my high frequency horn drivers weigh nothing and bass speakers are heavy and heavily loaded, as well.
I was told that we don't hear bass dixtortion as easily as high frequency distortion or inaccuracy.
WRONG!!!)

To my shock, I actually prefer listening at even lower levels as long as the bass reproduction is adequate.
Lower volumes reduce distortion even further.
Less driver excursion = less distortion, harmonic and otherwise.

Trying to solve apartment issues for people with poorly built walls, I actually suggest upping their lower bass capability and turning down the total volume.

Granted, this may not be an easy solution, but physics are physics.
No matter what mono subwoofer bullshit companies try to sell these days, don't be fooled.
(And never use a mono subwoofer except for mono sound.)
Good sound requires good amplifiers and good speakers.
I can tell you how to save money, but there are no shortcuts to decent audio.

The speakers posted spec 15hz to 23Khz, and those are not fantasy figures like most specs.
To reach that level of accuracy, I recommend four 18" bass drivers or equivalent, say by using many smaller drivers.
Preferably double that.

And I believe in live rooms too, even for recording.

All speakers distort less at lower volumes.
All speakers are more accurate at lower levels.


HOWEVER,
big pa systems are well past these levels now and are capable of very low frequency bass.

Many of the sound systems on the playa are very capable of producing deep and accurate bass without blaring at annoying levels for long distances.
The bass would still penetrate in the area.

Yes, we have proprioceptors in many areas of the body, but there are dimishing returns with using audio as a stimulus.
Audio, especially in open air is a logarithmic curve to add volume.

Nexus or the people that have produced their sound go into great detail on their webhouse about concern for accuracy over noise, and the pointlessness of excessive volume.
Still too loud on the playa, but they have thought about these issues and seem to understand them.


I went to a regional that was so loud that I could either not go into the active area or wear earplugs, or suffer.
Conversation was impossible.
No one outside of a few dancers wanted those levels.
At the nexus point between the speakers, I could feel my insides resonating, obviously very dangerous levels.
The dance area was maybe thirty feet, but everyone had their fun pissed on.
Much louder than burning man, on average.
It wasn't pleasant.
Why?

I like the people at the regional and have no plans to return.
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Re: Lasers in the eye - Serious injury, Please Read

Postby Risky » Tue Nov 29, 2011 10:20 am

ygmir wrote:
Snow wrote:HI WIFE! I never even saw you in BRC, not even once.

I even went looking for her, and could find her.

"The elusive Siren"


Oops. I don't come here that often anymore and missed this until now.
I was earlobe to ankle in the Temple project this year and camped all the way over at 915, instead of the the 3 o'clock Reno 'hood.
Most everyone was international, with very few folks from Reno.
We truly never stopped working, but I managed to party harder than ever before.
You would think that once the event started we could relax.
But they would call us on the radio for art tours and repairs and burn plans.
Someone always had to be available and meetings continued.
So the core group camped together so that we could constantly convene and troubleshoot.

I had an art support sticker and did drive my ass over to Terminal Village a few times.
They will always have a piece of my heart.

westnileraven wrote:Also I just really hate you laser-raping all the effigies...

oh shit! I am so using this term. Laser-raping! gigglesnort
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Re: Lasers in the eye - Serious injury, Please Read

Postby Ugly Dougly » Tue Nov 29, 2011 10:28 am

Image
I'm not bringing a power meter out to the playa to check every laser pointer.
But it's easy enough to snatch a pointer out of your average hippy's hands and fling it into the deep playa.
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Re: Lasers in the eye - Serious injury, Please Read

Postby gyre » Fri Dec 02, 2011 8:07 pm

Someone posted that they don't care about damaging their hearing.

Most people don't understand tinnitus.
It's not silence.

http://www.mirror.co.uk/news/top-storie ... -23569914/


A MAN stabbed himself to death after a rock concert left him with severe tinnitus, an inquest heard yesterday.

Robert McIndoe, 52, was unable to sleep for three months after seeing Them Crooked Vultures at the Brixton Academy, London.

The inquest heard he had previously taken an ­overdose at his home in Sydenham.

His psychiatrist, Dr Helen Stinson, said: “He accepted death as a side-effect of s­topping the noise.”

Wife Shirley said: “He just wanted not to be suffering.”
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Re: Lasers in the eye - Serious injury, Please Read

Postby westnileraven » Fri Dec 02, 2011 8:19 pm

no its loud as fuck. So far it has always faded in a day or two. Hence, earplugs or walking away from the speakers.
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Re: Lasers in the eye - Serious injury, Please Read

Postby Ugly Dougly » Sat Dec 03, 2011 12:30 am

It's always there for me. It would make me crazy if I wasn't already.
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