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Blackdevil77
07-28-2011, 06:49 PM
What usually effects the sound of a report? Is it the containment? The flash powder or both? For example, what would make a deeper sound or louder sound? Does slower burning flash make a deeper sound or faster burning?

Also, I've read online and on here about dark salutes, and have read that they have an extremely deep sound that "penetrates the soul." What is in dark salutes? I'd love to see Dave make a video on them.

PyroJoeNEPA
07-29-2011, 10:16 AM
Sound is affected by many things--distance, humidity, etc. The farther away from the report you are the sound will change. High frequencies are very directional [like a beam of light] and travel greater distances than the lower frequencies which are much more wide spread. The amount of moisture in the air affects the transmission of higher frequencies, also. So, the same report on a clear night would not sound the same as on a humid night at 100 feet in the air.
The burst of a heavy loaded shell is louder than a soft break shell--velocity of air being displaced....similar to difference of different caliber bullets coming out of a gun barrel.

As for the actual dark salutes, the formula is not to be toyed with by the inexperienced--it is friction and shock sensitive. Basically it contains Potassium Chlorate, Antimony TriSulfide, & Sulfur. Sorry, but I am not posting any exact formula. It is dark because it does not contain any aluminum which produces a high light output when it burns.
If you look at Dave's videos on the "Rocket Master" you will see[actually hear--not see] several of his rocket headers with dark salutes. They do have a lower sounding "thud" to them than a traditional flash report.

Blackdevil77
07-29-2011, 11:51 AM
Sound is affected by many things--distance, humidity, etc. The farther away from the report you are the sound will change. High frequencies are very directional [like a beam of light] and travel greater distances than the lower frequencies which are much more wide spread. The amount of moisture in the air affects the transmission of higher frequencies, also. So, the same report on a clear night would not sound the same as on a humid night at 100 feet in the air.
The burst of a heavy loaded shell is louder than a soft break shell--velocity of air being displaced....similar to difference of different caliber bullets coming out of a gun barrel.

As for the actual dark salutes, the formula is not to be toyed with by the inexperienced--it is friction and shock sensitive. Basically it contains Potassium Chlorate, Antimony TriSulfide, & Sulfur. Sorry, but I am not posting any exact formula. It is dark because it does not contain any aluminum which produces a high light output when it burns.
If you look at Dave's videos on the "Rocket Master" you will see[actually hear--not see] several of his rocket headers with dark salutes. They do have a lower sounding "thud" to them than a traditional flash report.

Thanks for the reply. No need to apologize, wasn't looking to make dark salutes or any salutes for that matter. I was just curious what was used that makes it dark and what gives it that deep thud.

As for the sound, I'm familiar with acoustics working with audio equipment for a decent chunk of time and know that bass sounds are omi-directional, which would normally mean they can be heard at greater distances than many high pitched sounds. Like when a kid in a honda drives by with the music blasting, as he distances himself, all you hear is "bump bump bump." I was just curious because I know someone who makes salutes and came up with his own secret recipe and he said it makes a much deeper sound then the traditional 70/30 mixture. I witnessed this for myself and he was right. I was wondering what characteristic in the mixture made it this way. same casing, same conditions, deeper sound. Does it actually burn slower? faster?

I'm gonna go look for that video now :D

Chris H
07-29-2011, 01:24 PM
A deeper sound typically indicates a slower burning composition. This is fairly easy to observe when listening to a black powder maroon vs. a flash powder salute. I've noticed that some people who cut their typical flash powder with sulfur or other things typically produce lower pitched sounds.

Blackdevil77
07-29-2011, 03:19 PM
A deeper sound typically indicates a slower burning composition. This is fairly easy to observe when listening to a black powder maroon vs. a flash powder salute. I've noticed that some people who cut their typical flash powder with sulfur or other things typically produce lower pitched sounds.

So while the lower pitched sounding salutes have a deeper sound to them, their actual explosive "power" isn't as great as others with a not so deep sound because the composition in the not as deep sounding salutes burn faster. Interesting. Like with speakers, the faster the cone movement, the higher pitched the sound, the slower, the deeper or "more bassy" the sound. The deeper sounding salutes probably don't push everything out as fast due to not burning quite as fast.

As you can probably tell, I am a sound nut lol. Always have been, always will

PyroJoeNEPA
07-29-2011, 03:34 PM
So while the lower pitched sounding salutes have a deeper sound to them, their actual explosive "power" isn't as great as others with a not so deep sound because the composition in the not as deep sounding salutes burn faster.
That is partially true--you also have to take into account the size of the charge & amount of air in the tube--A flash salute with 80% powder is louder than the same tube with 70% powder--but fill it to 90% and it doesn't have room for the combustion to take place. Soooo many variables. Look how little flash is in a firecracker & the high pitch report it gives--no room in a 1/4" paper sleeve for compression & expansion> BTW-I'm an audio engineer by profession [have 8 21" subs in my rental system :)]

Blackdevil77
07-29-2011, 03:59 PM
That is partially true--you also have to take into account the size of the charge & amount of air in the tube--A flash salute with 80% powder is louder than the same tube with 70% powder--but fill it to 90% and it doesn't have room for the combustion to take place. Soooo many variables. Look how little flash is in a firecracker & the high pitch report it gives--no room in a 1/4" paper sleeve for compression & expansion> BTW-I'm an audio engineer by profession [have 8 21" subs in my rental system :)]

lol that means your my type of guy :D

hmmm.... So optimum total compostion is about 80 percent of the tube/casing? Or that just makes it the loudest and not necessarily the deepest?

Chris H
07-29-2011, 05:23 PM
"Power" is a funny term when it comes to explosives, and it somewhat loses it's meaning. A lower pitched sound does not always mean less powerful, less energetic, or less damaging/destructive/forceful.

Optimal fill definitely depends on what you're doing. If you show up with an 80% full traditional bottom shot, I'm clearing the area and watching for flying steel.

pyro70_30
07-29-2011, 07:30 PM
The good DR. may not agree with with the 80% thing. Rumor has it that those are filled full and packed tight. If you've heard them they rock!

Blackdevil77
07-29-2011, 10:15 PM
The salutes the guy I know made where completely filled with his secret recipe mix. One thing I noticed is as his salutes age, they are not nearly as powerful or as loud. Why would this be?

whitepyro
07-30-2011, 07:11 PM
the powder may have settled over time and no longer will the powder reach the top, so his desired effect will not work. Just my opinion

Blackdevil77
07-30-2011, 08:49 PM
the powder may have settled over time and no longer will the powder reach the top, so his desired effect will not work. Just my opinion

Any way to safely fluff up the powder without opening it? Key word, SAFELY lol