Anyone know a place to measure exhaust dB w/ out a citation?
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Anyone know a place to measure exhaust dB w/ out a citation?
Just like the subject says. I am looking for a place in the Bay Area that can measure the sound output of the exhaust and provide a report.
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is it because you got a ticket for exhaust? if so, theres no way around it even if you get a report of how many dbs your car puts out 
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iphone mic works up to 110db:
http://iphone.iusethis.com/app/decibelmeter
http://iphone.iusethis.com/app/decibelmeter
"*Decibel Meter should be used for entertainment purposes; the iPhone’s built in mic is not sensitive enough for professional level sound metering."
That also doesn't state the required testing conditions that is normally used when verifying how many dB's an exhaust will output. Example - The mic must be X distance away from the object being measured. The surrounding area must be Y.
If you measure how many dB's an exhaust sounds in an open outdoor area vs inside a parking garage you should get a different number. So you really need to know proper testing criteria in order to develop an accurate test of sound.
That also doesn't state the required testing conditions that is normally used when verifying how many dB's an exhaust will output. Example - The mic must be X distance away from the object being measured. The surrounding area must be Y.
If you measure how many dB's an exhaust sounds in an open outdoor area vs inside a parking garage you should get a different number. So you really need to know proper testing criteria in order to develop an accurate test of sound.
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Jacob, are you trying to get the report for preemptive purposes? Also, WTF, did you put glasspacks on the Pilot or something?
The Sheriff's office can do sound readings, but if you're concerned that you're over the legal limit then you might not want to go that route.
The Sheriff's office can do sound readings, but if you're concerned that you're over the legal limit then you might not want to go that route.
Last edited by VRT MBasile; Nov 4, 2010 at 04:48 PM.
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iphone mic works up to 110db:
http://iphone.iusethis.com/app/decibelmeter
http://iphone.iusethis.com/app/decibelmeter
But for getting a rough idea of how you are in terms of legal limit, it tell you if you're in the ballpark- ('cause if it's louder than 105 it isn't legal)
If you're doing this to check for your own information go out to Treasure Island on the northeast/east side where there's nothing or any remote area late at night and measure it with an Iphone or anything really.
Otherwise you need to do this:
http://www.autorepair.ca.gov/80_BARR...evel_Cert.html
I thought about this and if you're trying to carry official documentation that your exhaust is within the legal limits, you can still go to the state ref and ask to have it tested to the best of my knowledge.
Otherwise you need to do this:
http://www.autorepair.ca.gov/80_BARR...evel_Cert.html
I thought about this and if you're trying to carry official documentation that your exhaust is within the legal limits, you can still go to the state ref and ask to have it tested to the best of my knowledge.
STEP 1
If you feel your vehicle's exhaust system has been modified or has deteriorated so that the noise level exceeds current standards, you should have the exhaust system repaired before proceeding to step 2.
OR
If you have reason to believe that your vehicle's exhaust noise level meets the current standards, proceed directly to step 2.
Note that citations have a court appearance date.]
[Timely action can help you avoid additional fines and penalties.]
STEP 2
Have your vehicle tested at a state Referee Center. To make an appointment, call the Referee Scheduling Center at (800) 622-7733. Have the citation and vehicle registration with you when you call. The Center will tell you any fees that will need to be paid for the test.
STEP 3
The Referee will conduct an exhaust noise level test in accordance with the Society of Automotive Engineers (SAE) standard J1169, May 1998, to determine if your vehicle's exhaust noise level exceeds the noise standard (95db).
If your vehicle meets the standard, the Referee will give you a "Certificate of Compliance." Take the certificate to the court (See Step 5).
If your vehicle does not meet the standard, the Referee will give you a report that lists the recorded decibel readings. Your vehicle must be repaired to meet the standard of not more than 95 decibels (See Step 4).
STEP 4
If your vehicle does not meet the standard, additional repairs must be made before you can make a second appointment with the Referee Scheduling Center.
STEP 5
Once your vehicle receives a "Certificate of Compliance" from a Referee Center, present the certificate to the court as proof that your vehicle is in compliance with California law.
NOTE: Inspection fees and any necessary repairs are your responsibility. You may also be required to pay a fine and other legal costs when reporting to the court. Also, note that most citations have a deadline. Timely repairs can help you avoid additional fines and penalties.
If you feel your vehicle's exhaust system has been modified or has deteriorated so that the noise level exceeds current standards, you should have the exhaust system repaired before proceeding to step 2.
OR
If you have reason to believe that your vehicle's exhaust noise level meets the current standards, proceed directly to step 2.
Note that citations have a court appearance date.]
[Timely action can help you avoid additional fines and penalties.]
STEP 2
Have your vehicle tested at a state Referee Center. To make an appointment, call the Referee Scheduling Center at (800) 622-7733. Have the citation and vehicle registration with you when you call. The Center will tell you any fees that will need to be paid for the test.
STEP 3
The Referee will conduct an exhaust noise level test in accordance with the Society of Automotive Engineers (SAE) standard J1169, May 1998, to determine if your vehicle's exhaust noise level exceeds the noise standard (95db).
If your vehicle meets the standard, the Referee will give you a "Certificate of Compliance." Take the certificate to the court (See Step 5).
If your vehicle does not meet the standard, the Referee will give you a report that lists the recorded decibel readings. Your vehicle must be repaired to meet the standard of not more than 95 decibels (See Step 4).
STEP 4
If your vehicle does not meet the standard, additional repairs must be made before you can make a second appointment with the Referee Scheduling Center.
STEP 5
Once your vehicle receives a "Certificate of Compliance" from a Referee Center, present the certificate to the court as proof that your vehicle is in compliance with California law.
NOTE: Inspection fees and any necessary repairs are your responsibility. You may also be required to pay a fine and other legal costs when reporting to the court. Also, note that most citations have a deadline. Timely repairs can help you avoid additional fines and penalties.
Last edited by manhands; Nov 4, 2010 at 05:58 PM.
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Whoa - this thread needs a "Jump to Conclusions Mat!" Haha..
Thanks for all the suggestions! I have an investigator in my family who is building a case and asked me about this. The question was along the lines of what one would do in order to LEGALLY prove that their exhaust were compliant.
So far, the Ref or Sherriffs will not test unless there is an associated citation. There is no citation in this case.
No, I am not planning on getting cited for exhaust - all my cars that are running have stock exhaust (which is probably a first for me). This question has nothing to do with me - just that when this person comes across any car related questions or situations, I usually get a call.
I also thought this would be a good "general interest" topic that a few people would be interested in.
Thanks!!
Thanks for all the suggestions! I have an investigator in my family who is building a case and asked me about this. The question was along the lines of what one would do in order to LEGALLY prove that their exhaust were compliant.
So far, the Ref or Sherriffs will not test unless there is an associated citation. There is no citation in this case.
No, I am not planning on getting cited for exhaust - all my cars that are running have stock exhaust (which is probably a first for me). This question has nothing to do with me - just that when this person comes across any car related questions or situations, I usually get a call.
I also thought this would be a good "general interest" topic that a few people would be interested in.
Thanks!!
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Whoa - this thread needs a "Jump to Conclusions Mat!" Haha..
Thanks for all the suggestions! I have an investigator in my family who is building a case and asked me about this. The question was along the lines of what one would do in order to LEGALLY prove that their exhaust were compliant.
So far, the Ref or Sherriffs will not test unless there is an associated citation. There is no citation in this case.
No, I am not planning on getting cited for exhaust - all my cars that are running have stock exhaust (which is probably a first for me). This question has nothing to do with me - just that when this person comes across any car related questions or situations, I usually get a call.
I also thought this would be a good "general interest" topic that a few people would be interested in.
Thanks!!
Thanks for all the suggestions! I have an investigator in my family who is building a case and asked me about this. The question was along the lines of what one would do in order to LEGALLY prove that their exhaust were compliant.
So far, the Ref or Sherriffs will not test unless there is an associated citation. There is no citation in this case.
No, I am not planning on getting cited for exhaust - all my cars that are running have stock exhaust (which is probably a first for me). This question has nothing to do with me - just that when this person comes across any car related questions or situations, I usually get a call.
I also thought this would be a good "general interest" topic that a few people would be interested in.
Thanks!!
Thread Starter
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Joined: Dec 2002
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From: Stockholm
Car Info: 2018 Golf R Variant
If you're doing this to check for your own information go out to Treasure Island on the northeast/east side where there's nothing or any remote area late at night and measure it with an Iphone or anything really.
Otherwise you need to do this:
http://www.autorepair.ca.gov/80_BARR...evel_Cert.html
I thought about this and if you're trying to carry official documentation that your exhaust is within the legal limits, you can still go to the state ref and ask to have it tested to the best of my knowledge.
Otherwise you need to do this:
http://www.autorepair.ca.gov/80_BARR...evel_Cert.html
I thought about this and if you're trying to carry official documentation that your exhaust is within the legal limits, you can still go to the state ref and ask to have it tested to the best of my knowledge.
Good to know. Thanks!
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What I was told is that domestic noise should not go over 50 dB, however, anything can constitute "noise pollution."
i wrote the author of one of the db meters for the iphone that pSOPER recommended.
i asked them if how they would rate the mic on the 3G (which is what i have). they replied that it is actually good.
so, if you wanna pretest your car, J1169 says that the mic of the SPL meter is to my at a 45 degress from the tip of the exhaust, at 20 inches away. it must be 8" off the ground.
they will test at 2 diff revs. i forget the percentage. one is like 55% of your max HP.
when a fellow i clubber bought some rims from me, i tested his aftermarket exhaust with my then radio shack spl meter. his exhaust failed, IIRC. he was like a 98 dBs. actually that was at his idle, not when revving to the specific value.
i asked them if how they would rate the mic on the 3G (which is what i have). they replied that it is actually good.
so, if you wanna pretest your car, J1169 says that the mic of the SPL meter is to my at a 45 degress from the tip of the exhaust, at 20 inches away. it must be 8" off the ground.
they will test at 2 diff revs. i forget the percentage. one is like 55% of your max HP.
when a fellow i clubber bought some rims from me, i tested his aftermarket exhaust with my then radio shack spl meter. his exhaust failed, IIRC. he was like a 98 dBs. actually that was at his idle, not when revving to the specific value.
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Sound check
The best way I know to test is sign up for a track day at Laguna Seca. They will tell you exactly what you are putting out. And you get a track day at Laguna Seca thrown in also. You can't beat that. The only problem is if you are over 92db you are done for the day unless you do something to quiet it up.
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I found this:
about a year ago, and I have used it to measure the output on my car & bikes just for my information. It's nice, because it provides a min/max, and I did use the method/measurements described in the BAR documents I found online at the time.
about a year ago, and I have used it to measure the output on my car & bikes just for my information. It's nice, because it provides a min/max, and I did use the method/measurements described in the BAR documents I found online at the time.