How Loud is Your Cobra ?

[Mdman352]

Weakest sound heard 0dB
Whisper Quiet Library at 6' 30dB
Normal conversation at 3' 60-65dB
Telephone dial tone 80dB
City Traffic (inside car) 85dB
Train whistle at 500', Truck Traffic 90dB
Jackhammer at 50' 95dB
Subway train at 200' 95dB
Level at which sustained exposure may result in hearing loss 90 - 95dB
Hand Drill 98dB
Power mower at 3' 107dB
Snowmobile, Motorcycle 100dB
Power saw at 3' 110dB
Sandblasting, Loud Rock Concert 115dB
Pain begins 125dB
Pneumatic riveter at 4' 125dB
Even short term exposure can cause permanent damage - Loudest recommended exposure WITH hearing protection 140dB
Jet engine at 100' 140dB
12 Gauge Shotgun Blast 165dB
Death of hearing tissue 180dB
Loudest sound possible 194dB

OSHA Daily Permissible Noise Level Exposure
Hours per day Sound level
8 90dB
6 92dB
4 95dB
3 97dB
2 100dB
1.5 102dB
1 105dB
.5 110dB
.25 or less 115dB




NIOSH Daily Permissible Noise Level Exposure
Hours per day Sound level
8 85dBA
6 86dBA
4 88dBA
3 89dBA
2 90dBA
1.5 92dBA
1 94dBA
.5 97dBA
.25 or less 100dBA
0 112dBA

Perceptions of Increases in Decibel Level
Imperceptible Change 1dB
Barely Perceptible Change 3dB
Clearly Noticeable Change 5dB
About Twice as Loud 10dB
About Four Times as Loud 20dB


Sound Levels of Music
Normal piano practice 60 -70dB
Fortissimo Singer, 3' 70dB
Chamber music, small auditorium 75 - 85dB
Piano Fortissimo 84 - 103dB
Violin 82 - 92dB
Cello 85 -111dB
Oboe 95-112dB
Flute 92 -103dB
Piccolo 90 -106dB
Clarinet 85 - 114dB
French horn 90 - 106dB
Trombone 85 - 114dB
Tympani & bass drum 106dB
Walkman on 5/10 94dB
Symphonic music peak 120 - 137dB
Amplifier, rock, 4-6' 120dB
Rock music peak 150dB


NOTES:

One-third of the total power of a 75-piece orchestra comes from the bass drum.
High frequency sounds of 2-4,000 Hz are the most damaging. The uppermost octave of the piccolo is 2,048-4,096 Hz.
Aging causes gradual hearing loss, mostly in the high frequencies.
Speech reception is not seriously impaired until there is about 30 dB loss; by that time severe damage may have occurred.
Hypertension and various psychological difficulties can be related to noise exposure.
The incidence of hearing loss in classical musicians has been estimated at 4-43%, in rock musicians 13-30%.
Recent NIOSH studies of sound levels from weapons fires have shown that they may range from a low of 144 dB SPL for small caliber weapons such as a 0.22 caliber rifle to as high as a 172 dB SPL for a 0.357 caliber revolver. Double ear protection is recommended for shooters, combining soft, insertable ear plugs and external ear muffs.
Statistics for the Decibel (Loudness) Comparison Chart were taken from a study by Marshall Chasin , M.Sc., Aud(C), FAAA, Centre for Human Performance & Health, Ontario, Canada. There were some conflicting readings and, in many cases, authors did not specify at what distance the readings were taken or what the musician was actually playing. In general, when there were several readings, the higher one was chosen.

[AL427SBF]

Originally Posted by Mdman352

Weakest sound heard 0dB
Whisper Quiet Library at 6' 30dB
Normal conversation at 3' 60-65dB
Telephone dial tone 80dB
City Traffic (inside car) 85dB
Train whistle at 500', Truck Traffic 90dB
Jackhammer at 50' 95dB
Subway train at 200' 95dB
Level at which sustained exposure may result in hearing loss 90 - 95dB
Hand Drill 98dB
Power mower at 3' 107dB
Snowmobile, Motorcycle 100dB
Power saw at 3' 110dB
Sandblasting, Loud Rock Concert 115dB
Pain begins 125dB
Pneumatic riveter at 4' 125dB
Even short term exposure can cause permanent damage - Loudest recommended exposure WITH hearing protection 140dB
Jet engine at 100' 140dB
12 Gauge Shotgun Blast 165dB
Death of hearing tissue 180dB
Loudest sound possible 194dB

OSHA Daily Permissible Noise Level Exposure
Hours per day Sound level
8 90dB
6 92dB
4 95dB
3 97dB
2 100dB
1.5 102dB
1 105dB
.5 110dB
.25 or less 115dB




NIOSH Daily Permissible Noise Level Exposure
Hours per day Sound level
8 85dBA
6 86dBA
4 88dBA
3 89dBA
2 90dBA
1.5 92dBA
1 94dBA
.5 97dBA
.25 or less 100dBA
0 112dBA

Perceptions of Increases in Decibel Level
Imperceptible Change 1dB
Barely Perceptible Change 3dB
Clearly Noticeable Change 5dB
About Twice as Loud 10dB
About Four Times as Loud 20dB


Sound Levels of Music
Normal piano practice 60 -70dB
Fortissimo Singer, 3' 70dB
Chamber music, small auditorium 75 - 85dB
Piano Fortissimo 84 - 103dB
Violin 82 - 92dB
Cello 85 -111dB
Oboe 95-112dB
Flute 92 -103dB
Piccolo 90 -106dB
Clarinet 85 - 114dB
French horn 90 - 106dB
Trombone 85 - 114dB
Tympani & bass drum 106dB
Walkman on 5/10 94dB
Symphonic music peak 120 - 137dB
Amplifier, rock, 4-6' 120dB
Rock music peak 150dB


NOTES:

One-third of the total power of a 75-piece orchestra comes from the bass drum.
High frequency sounds of 2-4,000 Hz are the most damaging. The uppermost octave of the piccolo is 2,048-4,096 Hz.
Aging causes gradual hearing loss, mostly in the high frequencies.
Speech reception is not seriously impaired until there is about 30 dB loss; by that time severe damage may have occurred.
Hypertension and various psychological difficulties can be related to noise exposure.
The incidence of hearing loss in classical musicians has been estimated at 4-43%, in rock musicians 13-30%.
Recent NIOSH studies of sound levels from weapons fires have shown that they may range from a low of 144 dB SPL for small caliber weapons such as a 0.22 caliber rifle to as high as a 172 dB SPL for a 0.357 caliber revolver. Double ear protection is recommended for shooters, combining soft, insertable ear plugs and external ear muffs.
Statistics for the Decibel (Loudness) Comparison Chart were taken from a study by Marshall Chasin , M.Sc., Aud(C), FAAA, Centre for Human Performance & Health, Ontario, Canada. There were some conflicting readings and, in many cases, authors did not specify at what distance the readings were taken or what the musician was actually playing. In general, when there were several readings, the higher one was chosen.

"Weakest sound heard 0dB"
With that as the opener, no need to read the rest lol

[RET_COP]

I took an industry standard reading at .5m or about 20” away from the tip of the exhaust on the same plane at a 45 degree angle, (A) setting on asphalt. I have louvered mufflers installed backwards.

idle 95dB
3000rpm 110dB
At 10ft away idle same plane and angle 85dB
At 20ft away idle same plane and idle 80dB