how can i copy a horn? i want to copy a specific horn. Dimensions: 12" W x 7" H x 7" D.
what materials should i use?
what materials should i use?
Standard calibration for a theater is to use a minus 20 pink noise signal ands set each channel to 85 from a seat 2/3 back in the audience. The sub also uses a bandlimited signal and should be set 10 dB louder (based on sine wave tests as pink noise would have a distinctly different bandwidth).
This means that the 5 main channels should be capible of 105 each and the sub of 115. Put them all together and....you do the math.
On the other hand....I have gone into a Simex theater that I had calibrated in such a manner and played back a loud sound track at the calibrated level (a loud section of Iron Man) and using a class 2 meter on "fast" and "C" not measuring any higher than 93. This was on a soundtrack that the mixer assured me frequently peaked to 0 on his workstation. This is primarily an indication of how a sound level meter will under read peaks.
So if you measured 110 (C) in a theater I would be very surprised. I also think the patrons would be complaining nearly as loudly to the management.
In my experience more theaters are set below the calibration level than at or above. The trailers are "loud" and patrons complain so they edge the levels down until the complaints stop.
David
This means that the 5 main channels should be capible of 105 each and the sub of 115. Put them all together and....you do the math.
On the other hand....I have gone into a Simex theater that I had calibrated in such a manner and played back a loud sound track at the calibrated level (a loud section of Iron Man) and using a class 2 meter on "fast" and "C" not measuring any higher than 93. This was on a soundtrack that the mixer assured me frequently peaked to 0 on his workstation. This is primarily an indication of how a sound level meter will under read peaks.
So if you measured 110 (C) in a theater I would be very surprised. I also think the patrons would be complaining nearly as loudly to the management.
In my experience more theaters are set below the calibration level than at or above. The trailers are "loud" and patrons complain so they edge the levels down until the complaints stop.
David
-20dB pink noise contains +6dB peaks.
If that is raised by 20dB, then will the peaks clip?
Why is the bass channel set to +10dB relative to the main channels?
If that is raised by 20dB, then will the peaks clip?
Why is the bass channel set to +10dB relative to the main channels?
Pink noise has a Gausian distribution with even larger peaks statistically possible. Using a -20 level keeps it well below clipping in practice. The pink noise is just used for calibration. The intention is that any signal of the digital recording recorded at -20 will play at 85 in the theater.
Plus 10 calibration for the sub allows it 10 dB more headroom (it can play to a theoretical 115 rather than 105). This is to allow a peak level frequency distribution with more potential at the low end, as would benefit action movies. This is written into the SMPTE and Dolby standards. Dubbing studios follow the same practice, so there should be good translation from soundstage to cinema.
David
Plus 10 calibration for the sub allows it 10 dB more headroom (it can play to a theoretical 115 rather than 105). This is to allow a peak level frequency distribution with more potential at the low end, as would benefit action movies. This is written into the SMPTE and Dolby standards. Dubbing studios follow the same practice, so there should be good translation from soundstage to cinema.
David
This is a very broad question as there are dozens of ways to do this, but all of them require a knowledge of manufacturing and prototyping techniques. For example, you could just do a 3D drawing and have them machined on a CNC machine, or a solids printer, except that method would cost you a whole lot of money. The cheaper you try to make them the more complex the process becomes. The most common materials are fiberglass and injection molding. I use polyurethane. You can cut them out of solid wood if you like, but again, that is very time consuming.
If you have a specific device you want to copy then make a mold from it.
Specifics
What driver will you be using with the horn you want to copy?
Is it the same as the one normally used with this particular horn?
Please provide manufacturer and model numbers for both.
Unless you will be making a lot of them, it probably would be less costly to just buy the horns you want.
Regards,
WHG
What driver will you be using with the horn you want to copy?
Is it the same as the one normally used with this particular horn?
Please provide manufacturer and model numbers for both.
Unless you will be making a lot of them, it probably would be less costly to just buy the horns you want.
Regards,
WHG
Yowza. I routinely listen to my Summas at levels that are 10-20dB louder than that.
Pat,
do your ears still work?
Routinely destroying hearing with 98dB to 108dB of average levels is banned in most industrial/commercial noisy environments.
do your ears still work?
Routinely destroying hearing with 98dB to 108dB of average levels is banned in most industrial/commercial noisy environments.
Damage potential depends on duration as well as level. 108 dB is not serious if it is for temporary peak levels. The OSHA standards refer to sustained noise levels, not music. Rock concerts regularly exceed these levels for hours. And yes, those are dangerous.
Pat, is comparing his routinely listening level to average levels of 88dB.
That is not peaks, nor short term transients.
It is averages.
That is not peaks, nor short term transients.
It is averages.
At a recent lecture by Floyd Toole he stated that the "85dB for 8 hours" OSHA standard was designated not for guaranteeing no hearing loss but rather for still being able to comprehend speech at retirement age.....
Not sure where that came from but it wouldn't be too surprising.
As Lidia often points out to me, there is no known relationship between levels and hearing loss. We know that higher levels have the potential for damage, but a one-to-one relationship between level and loss does not exist. So any specification is going to be a guess - at best.
And let's not forget about driving in a car with the windows or top down. (Or heaven forbid a motorcycle!) The levels can be upwards of 110 dB and that can be for hours. That's why I don't drive convertibles or with my windows down. If I am going to worsen my hearing I'd rather it be with music.
And let's not forget about driving in a car with the windows or top down. (Or heaven forbid a motorcycle!) The levels can be upwards of 110 dB and that can be for hours. That's why I don't drive convertibles or with my windows down. If I am going to worsen my hearing I'd rather it be with music.
Sounds like: smoking won't guarantee lung cancer but it ups the odds considerably.
I've heard that American males, as a group, have generally worse hearing in the left ears while British males exhibit the same in reverse. This was attributed to left had driver here and right hand drive over there.
Motorcyclists should, overall, be in better balance!
If you're driving down the road in the average midsize car, and you are listening to your music at an average of 20dB louder than the ambient noise, you are listening at about 92dB*
I listen to a lot of EDM, and I've noticed that due to the synthetic bass lines, you can have the bass bumped by as much as 30-40dB and it still sounds "tight."
So in that scenario, the midrange would be somewhere around 92dB, the highs would be around 82-87dB, and the bass would be a whopping 122-132dB
The reason that this works in EDM is the lack of harmonics. Real drums have harmonics, but EDM is mostly synthetic sounds, so monster bass drops are felt not heard.
* http://media.caranddriver.com/files/honda-civic-ex-coupe.pdf
^^ db ratings from car and driver
Pretty much identical situation. Some people will loose their hearing with no noise contribution, others don't ever see damage even in a loud environment. There is only the stats, nothing certain.
Hearing Loss
The story is perhaps apocryphal, but it is said that the venerable bandleader Buddy Rich could hear a potato chipped being crunched by a band member seated all the way at the back of the bus. This, despite drumming in incredibly loud 10-15 piece jazz bands for 40+ years. Other drummers I know have definitely not been so lucky.
The story is perhaps apocryphal, but it is said that the venerable bandleader Buddy Rich could hear a potato chipped being crunched by a band member seated all the way at the back of the bus. This, despite drumming in incredibly loud 10-15 piece jazz bands for 40+ years. Other drummers I know have definitely not been so lucky.
NIHL Exists
Recent studies have shown that exposure to harmful sounds triggers the formation of molecules (free radicals) inside the inner ear that damage or kill the sensory hair cells located there. These cells convert sound energy into electrical signals that are sent to the brain to facilitate hearing. While there are other causes of hearing loss, the debate continues over the intensity and duration required to trigger the onset of Noise Induced Hearing Loss (NIHL). Even though susceptibility to such damage varies between individuals, there should no doubt that this phenomenon does occur when the ear is acutely exposed to acoustic energy, irrespective of the source from where it comes.
For more information see:
Noise Induced Hearing Loss | American Hearing Research Foundation
Regards,
WHG
Recent studies have shown that exposure to harmful sounds triggers the formation of molecules (free radicals) inside the inner ear that damage or kill the sensory hair cells located there. These cells convert sound energy into electrical signals that are sent to the brain to facilitate hearing. While there are other causes of hearing loss, the debate continues over the intensity and duration required to trigger the onset of Noise Induced Hearing Loss (NIHL). Even though susceptibility to such damage varies between individuals, there should no doubt that this phenomenon does occur when the ear is acutely exposed to acoustic energy, irrespective of the source from where it comes.
For more information see:
Noise Induced Hearing Loss | American Hearing Research Foundation
Regards,
WHG
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According to Lidia, the PhD in this subject, hair damage (breakage, etc.) is far more prevalent than nerve damage in hearing loss.