On ships, for ear protection in areas with a >85dB(A) level.
(adoption of IMO resolution A468, code on noise levels on board ships)
I was thinking safety, as far as I can tell 140dB continuous at 100kHz is OK. I don't know the efficiency of those piezo resonators, but they are driven at resonance. At 20% efficiency one could estimate 50W/sq meter or so out of those audio spotlight panels that's 141 dB SPL (back of the envelope of course). The conversion efficiency was tiny when I heard them the resulting audio was iPod level, hopefully that has improved.
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For generation of impulse noise, or termination of long term bass???
For me, the bass is loud enough in the venue when I can no longer focus my eyes..
I understand the needs of the establishments playing the music, and would prefer to approach limits and noise ordinance enforcement in a reasonable fashion. As such, I would like to make recommendations to the local code writing authority which are not excessively restrictive, but are reasonable and yet protect the nearby residents who are being woken up at 3 in the morning with pounding bass.
It doesn't help that the offending establishment is a stick built building, the sheetrock and external siding isn't a good 20 to 50 hz block.
It may be that I'll have to recommend code take measurements using both A and C to get a handle on the magnitude of the problem and if using C would even be useful.
My word
Just the numbers scare me. I personally would be a tad more cautious than to subject humans to those levels of acoustic power, even more so since the target audience is unaware of exposure. I don't know if exposure to this is harmful to long term hearing, but I could see lawsuits resulting. The frivolity of the lawsuits would be very difficult for determine given the rampant use of earbuds at levels exceeding osha, and the lack of hard data in support of or against such levels of exposure.
jn
I was on a city Noise Abatement Commitee once. There are 2 issues for the city: Safety and annoyance levels. A very low level (spl) can be an annoyance to someone. So, that was the hardest to deal with as a law. But then crazy things are done -- like a hospital build beside the busiest street. (cheap land price for the city? Money always trumps everything else, it seems).
-RNM
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People's low tolerance levels can be amazing. I was on a managing board once and we had an owner that could not tolerate the sound of the hot water loop (we had central hot water for 41 units so it had to ciculate). You had to strain to hear anything, I don't think it would even register over quiet background.
Yeah, people's tolerances for different sounds is all over place. My girlfriend gets upset if I make lip smacking sounds when I eat. I can't say I'm even sure what sound it is that I make ... to me it doesn't even register but she'll turn to me and give me dirty looks or hit me when she hears it.
I know eating sounds can be a real problem for some people to the point they can't tolerate eating with family and friends. It requires some psychological work, like cognitive behavior therapy exercises to overcome it. Some people just won't do that.
I know eating sounds can be a real problem for some people to the point they can't tolerate eating with family and friends. It requires some psychological work, like cognitive behavior therapy exercises to overcome it. Some people just won't do that.
Why bother about all this discussion Here a real one for sale:
CTC Blowtorch A Masterpiece Preamp | Solid state | AudiogoN - The High-end Audio Community
Here a real one for sale:CTC Blowtorch A Masterpiece Preamp | Solid state | AudiogoN - The High-end Audio Community
I don't know, but doubt it since this was not high volume product. My question - what kind money does it take to get that UL stamp on a product? Or is free?
Bad memories for me, my father forbad hot soup at dinner because of the sounds people made trying to eat it.
I'm going to through out a number of let's say $20,000 for all the paperwork and testing to get a UL ratings and sticker for product by the time all is said and done. So if you only build 40 units you have to figure that is $500.00 cost per unit for that sticker. I guess you could say it is cheap insurance at the same time.
I know city of Los Angeles Electrical Testing Tab used to be just under $1k. That is almost as good a stamp as UL. The unit for sale at A-Gon is an EU voltage. Does it have CE cert? Oh yeah, and ROHS?
UL approval isn't very useful, hell hair dryers and toasters pass. CE and safety testing varies depending on how much you want done and if you want the papers. Ce is currently $5K and up safety is $12K and the cost of the destroyed products. You can self certify for CE but you better make sure it passes or you can be assured of big fines.
John I was doing some reading by the FAA on airplane electrical systems and they have a nice chart on approved contact materials after many years of study. They like Silver on Silver and Gold on Gold bifurcated for low level signal.
If it's good enough for peoples lives it might just work on the Blow Torch Mine currently uses corrosion on corrosion Soon to change!
If it's good enough for peoples lives it might just work on the Blow Torch
Mine currently uses corrosion on corrosion Soon to change!Hair dryers with proper creepage, clearances, and double insulated construction pass, yes.
There are a lot of questionable mains powered hi-fi products out there and I would not be surprised if some of them would fail and are possibly unsafe.
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