Page 1 of 1
Audacity and a wireless mic
Posted: Sun Aug 30, 2009 2:22 pm
by boyntonstu
We have a Sennheisser Digital 1000 wireless microphone system.
Instead of using my MP3 watch recorder, I set up the wireless mic and I was able to use my PC sound card to record all sounds transmitted from the garage.
If I get a time break, i will compare the MP3 recording to the sound board recording.
MP3 compression vs none.
BoyntonStu
Posted: Sun Aug 30, 2009 2:47 pm
by jrrdw
Would this be the sounds of your cannon firing? And ammo hitting it's target?
Posted: Sun Aug 30, 2009 3:10 pm
by cannon monkey
if like ur tring to find out fps put ur wireless mic middle of the targe range 10 feet from barrel 10 feet from targe or what ever ur hitting
find the time from exploding sound of the cannon then hitting target
divid by 20 there ur fps
Posted: Sun Aug 30, 2009 3:51 pm
by jimmy101
cannon monkey wrote:if like ur tring to find out fps put ur wireless mic middle of the targe range 10 feet from barrel 10 feet from targe or what ever ur hitting
find the time from exploding sound of the cannon then hitting target
divid by 20 there ur fps
That positioning isn't correct. Your mike is now splattered with spud since it is in the line of fire.
I suspect boyntonstu knows more than enough to figure out how to correct for the mic placement and how to calculate the average velocity from the two sounds. Personally, I would lean towards putting the mic much closer to the target than to the muzzle, heck I would probably tape the mic
to the target. The muzzle blast is probably going to be much louder than the sound of the ammo hitting the target. Correcting for the different source to mic distances is pretty trivial.
-----
It'll be interesting to see what the MP3 compression software does to the signal fidelity.
If this was used on a combustion gun there is a chance that you would also get a discernable signal from the RF noise created by the ignition spark.
Posted: Sun Aug 30, 2009 3:55 pm
by Technician1002
jimmy101 wrote:That positioning isn't correct. Your mike is now splattered with spud since it is in the line of fire.
I suspect boyntonstu knows more than enough to figure out how to correct for the mic placement and how to calculate the average velocity from the two sounds. Personally, I would lean towards putting the mic much closer to the target than to the muzzle, heck I would probably tape the mic to the target. The muzzle blast is probably going to be much louder than the sound of the ammo hitting the target. Correcting for the different source to mic distances is pretty trivial.
-----
It'll be interesting to see what the MP3 compression software does to the signal fidelity.
If this was used on a combustion gun there is a chance that you would also get a discernable signal from the RF noise created by the ignition spark.
This calls for a stereo recording with two microphones.. If using two, use two of the same kind. The digital has an encoding and decoding delay. If compared to an analog directly wired mic, it will skew the time by this delay.