2 Good Subs > 1 Great Sub for HT? And more questions. - Page 4

Beeman, your advice is legitimate in your caution towards hearing loss. But I thought you said you were getting off your soap box after the first post on the matter?

You'll note from all the hearing loss recommendation charts that time of exposure is added to the mix to account for hearing damage too. A few brief moments from a demo scene will not a deaf man make.

I'll wager that most of us with crazy systems don't always listen at crazy volumes. My personal preference for movie playback is about -12dB from reference with the subs about 6 dB hot.

However -- if there is an awesome scene, (and my wife isn't home) I'll crank it up to reference + so that I can experience what it would be like to be on location at the set, even if only for a few minutes.

If watching the movie Open Range and I want to be a part of a old west gunfight, I'll crank that scene up for a few moments. It sounds like I'm on a shooting range with the right equipment. It's truly nothing short of the real thing!
If I'm watching the movie War of the Worlds and want to feel the terror and awe of a unknown entity rising from the earth beneath the city pavement - I'll turn it up to reference. I don't want to turn it up and hear a sub farting or clanking. These high capability systems allow for unfettered realism.

I want the realism to scale with the volume knob!

If someone wants to listen to their music at 25dB and finds 40dB too loud, as I've seen you state - then they need not have any interest in a sub that can produce realistic levels of gunfire playback.

And if people will stop trying to personally engage me in spurious argument, I'd love to.


Again with confusing hearing loss with deafness. I've not posted a word about one going deaf and I've posted nothing about an acute event but I have posted about loss of hearing sensitivity. As the microscopic hairs are permanently damaged due to chronic abuse, the loss of sensitivity is cumulative in nature. That's an unequivocal fact.

As to live fire exercises, that's why it's advised to wear ear guards and when using power equipment, to do the same. I guess some people don't wear ear guards at the range or when using a backpack blower, don't use ear guards but protecting one's hearing is why this safety measure is encouraged and sometimes, OSHA mandatory.

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Edited by BeeMan458 - 2/14/13 at 8:09am

Yep, and also you didn't mention that these recommendation charts for exposure to hearing are A-weighted. So subwoofers are even less of a concern.

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=standards&p_id=9735

Those pair of orbit shifters were unlike anything I've ever heard or felt.

Yes - 134dB to 137dB peaks of subwoofer bass in a home will crack floor grout on a suspended wooden floor above the basement theater room.

proof

http://www.avsforum.com/t/1387178/archaeas-kansas-city-blind-subwoofer-shootout-2012/100_20#post_21501576

It also will wreck optical drives (my bluray and hddvd drives)
It will also knock projector alignment off internally and make colors fail - my epson 8350.
And do the tired old tricks of knocking down pictures and 2lb wooden camel statues.


My captivators are not quite as strong as the orbit shifters. They will only unscrew lightbulbs or simply make filaments fail, unstack cans in my pantry, knock over pictures, loosen drywall, knock projectors physical mounts out of alignment, ill-adjust projector focus rings, and make sleeping bags fly. When I want to start physically destroying my things with obscene and awesome capability I can always step up to the orbit shifters --- or buy a setup like carp's or popalocks.

hahaha.

All the above evidences of acoustic energy are true and things I have experienced with JTR equipment. Many I have pictures and videos of.



But all of these fun intense experiences for only a few moments at a time so as not to induce hearing loss.

Now you're just ducking and dodging as you do the obvious side step. It doesn't matter "A" weighting or "C" weighting as dB is dB and the weighting has to do with how the curve is set up. If doing a <250hz, you want "C" weighting if higher, use "A" weighting. If low levels are being measured, then "A" weighting is the preferred weighting of choice.

Weighting.

OSHA's standards are a little less stringent:

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=standards&p_id=9735

Duration per day, hours | Sound level dBA slow response
____________________________|_________________________________
|
8...........................| 90
6...........................| 92
4...........................| 95
3...........................| 97
2...........................| 100
1 1/2 ......................| 102
1...........................| 105
1/2 ........................| 110
1/4 or less................| 115



And as Luke pointed out, these are A-weighted numbers.

So, 2 hours at 100 dB is OK, or 15 minutes at 115 dB is OK, according to OSHA, but not the BeeMan. I doubt there is a single movie with a cumulative of 15 minutes at 115 dB. And that "cumulative" 15 minutes is spread out over 2+ hours. Listening to a movie at Reference Level is just not nearly as dangerous as the BeeMan makes it out to be.

Craig

(Sorry Luke, I was searching and typing while you posted. Didn't mean to duplicate your post.)

+1. The reason why noise exposure standards are referenced to 'A' weighting is that the potential for hearing damage relative to frequency content closely coincides with the 'A' weighted scale.

Did you forget you're in the "Subwoofer" forum? Did you actually *read* the link you posted?

My, my. Movie caused hearing loss.

Never have understood people's need to blow off rational conversation. Hearing loss is cumulative and hearing loss can't be fixed. Once gone, it's gone and the best one can do is the addition of hearing aids. It's your hearing so as I posted earlier, do with it what you will but beware when telling others, there's nothing to be concerned about as the jury's not out on this question.

There you go with the irrational questions again. If you have something specific to reference, do. It's your hearing, not mine. Do with it what you will but if one is responsible, then they're responsible for advice regarding >120dB sound reproduction and the harm it can/will cause.

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Edited by BeeMan458 - 2/14/13 at 8:48am

Side step I am presenting public scientific data that is quite pertinent to the discussion. You are pulling stuff out of your ... as well as trying to tell people on an audio forum that movies reproduced even remotely close to the level they were recorded for is damaging.

A db is not a db as far as our hearing is concerned audibly or concerning safe listening levels, it is frequency dependent.

No I'm not as I've posted supporting links.

It's your hearing. I've posted factual links to government sponsored and industry related sites. As I posted, it's just a heads up post and some people care about this stuff, and others don't and yes, a dB is a dB despite frequency differences. And if you're blasting the subs at >120dB, then you're more than likely you're trying blasting your speakers at >110dB.

Hearing loss is cumulative and can't be restored and if you want to trash the linked information I've posted, go for it. Again, it's your hearing and you're welcome to do with it, what you will. If anybody wants to trash my warning, they're welcome to as it too is their hearing, to do with, what they will.

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Edited by BeeMan458 - 2/14/13 at 9:05am

I don't believe this is correct. If the content you are measuring contains anything below 500hz, then the SPL values will be different using C and A weighting. For example, if you are measuring your sub(s) using the AVR internal test tone, the SPL reading will be different if using C weighting vs A weighting. Or take a movie scene with very strong content below 30hz. Listening to that scene hitting a peak of 100 dBA is going to be a lot louder overall then listening at a level peaking at 100 dBC. So 85 dBA and 85 dBC are not necessarily the same.

-Mike

Wait.... So "THX Reference Level" is too loud and can cause hearing loss? I thought THX standards were YOUR reference:

So, whenever it suits your purpose, you can refer to a higher authority, but then when it suits a different purpose, you can dismiss that same higher authority? And you think my posts are irrational?

Yes there will as for low level measurements, it's recommended to use "A" weighting. But at high levels, the difference is removed but if <250Hz, one should go to "C" weighting. I posted information regarding weighting curves.

It's your hearing, do with it what you will. I can't make this point any more abundantly clear.

Again with you making stuff up and not reading what I have to post. THX is reference level and has nothing to with me. Aliens abduct me and it's off to a parallel universe, THX reference will still be here as I have absolutely nothing to do with the THX reference standard and 120Hz has nothing to do with >120dB SPL and nowhere am I dismissing THX reference standards as yes, your posts to me are irrational.

Please, let it go.

In both cases, you "refer to", (i.e., you "reference"), THX standards. In one case you use them as the higher authority to support your argument about the LPF of LFE. In another case, you dismiss them as too loud and have the potential to cause hearing loss or damage. So, is THX the "boss" or not?

Notice how you intentionally leave out any context of every thing I post? Being boss of the LFE channel standards has absolutely nothing to do with advice regarding >120dB SPL

As one tries to parody my warning, the very funny movie, "Airplane," came out in 1980. In the the thirty years since the movie came out, as of 2010, there have been over 23,000 fatalities. Yes, things have gotten better and have because restrictive safety measures have been put in place. I'm not suggesting that safety measures be put in place but don't blow off rational warnings and then say you're being a rational person.

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Edited by BeeMan458 - 2/14/13 at 10:24am

I read all your posted links, even some of the google search.

I have researched hearing and understand, you should too. This topic like many you argue (and are wrong about I might add) about have been discussed here many times before. It seems you can do a google search, how about trying the search function here. A few good posts here.

http://www.avsforum.com/t/1445870/is-reference-level-loud-to-you

I guess you fall in the -15 or more category.

Is reference too loud? It depends on room (reflections yada, yada, yada) equipment (distortion/compression), personal preference....

Reference is an industry standard, preference is exactly that.

Trying to argue that -60 is acceptable for movie audio reproduction, pointless.

Especially since I never argued that it was. This is why I post that this isn't a rational interchange as I never posted what you're suggesting as that particular discussion revolved around someone telling me that I should only be able to, if that, bearly hear at -60 and if I can easily hear it, my settings are all FUBAR'd. Well, I and my wife can and there's nothing FUBAR'd about the settings and somebody doesn't want to let this point go.

Again, it's your hearing, you've only got one set of hairs inside your inner ear and you're welcome to do with them what you want as once gone, they're gone. Just saying.

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Edited by BeeMan458 - 2/14/13 at 10:57am

poor original poster...

Better start a new thread, this one has decended into madness.

"Beam me up, Scotty. There's no intelligent life down here."

Good for you. Unnecessarily, you and others make a fight out of a simple warning/concern and then blame me for the damage you guys cause. Reads to me like some here don't want the truth about their hobby getting out.

How about treating my original comment in the spirit it was intended, a comment of warning regarding >120dB and nothing more.

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Edited by BeeMan458 - 2/14/13 at 11:06am

You're close. The reason for the 'A' scale is that it resembles the inverse of an equal loudness chart. The threshold of damage to hearing is very much the same as an equal loudness chart. The damage done by a 1kHz tone at 100dB requires at least 120dB at 30Hz, 130dB at 20Hz. When you measure with 'A' weighting the scale automatically applies correction to determine if the source is exceeding standards or not, irrespective of the frequency bandwidth of the source. If you measured with 'C' weighting or no weighting you'd have no idea if the source was actually exceeding the damage threshold or not.
He may have read it, he certainly didn't understand it. At any rate, if you want to measure your subs to be sure you're not damaging your hearing with them then by all means do so with an a 'A' weighted meter. Your subs can be putting out 120dB or more and you'll be reading 100dB or less on your meter.

I have read your self determined setup guides. Its FUBAR'd. But thanks again for the warning, its the concerts and car stereo's that get me, not my home system. A deer farting in the woods 20ft away would drown out sound effects to a system at -60.

Here is a link as useful as yours.

http://www.google.com/#hl=en&tbo=d&output=search&sclient=psy-ab&q=deer+farting+in+woods&oq=deer+farting+in+woods&gs_l=hp.3...1045.4593.0.4855.21.21.0.0.0.0.231.3096.1j18j2.21.0.les%3B..0.0...1c.1.3.psy-ab.9zJf964gh90&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.&bvm=bv.42452523,d.b2U&fp=61c122104a8a681d&biw=1517&bih=741

It looks to me like the OP has many here that understand audio and can help out any further posts.

Again, we're not having a rational conversation as you're obviously posting as if you're not reading what I've posted. I've repeatedly posted that the -60 MVC setting is verified, based on sound meter readings, which are empirically verified, using a calibrated sound meter and the sound meter provided SPL measurements, corroborate that the system is set up correctly as the measured room reading, at main listening position, agrees with what is expected when the MVC is set to -60.

Those are the facts and no amount of lambasting or personal insults will change these facts.

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Edited by BeeMan458 - 2/14/13 at 12:24pm

Well you got that part right!

All I have to say on this:

Hey guys. Just want to let everyone know that the block feature is pointless when the person you block happens to be the most quoted person on the forum.

Think of those precious minutes you are never going to get back.

Just sayin...