Noise Limit

Magila · Forum Addict

Noise Limit

simpson · Rehab Dropout...

How does it work i go to National event my car's to loud, I go to a State run event no problem,at the MMC we took our own noise testing equipment guess what even at the rev cut it was under 95 db.
Rules say 30 mts from the car and test should be at 3000 rpm. At Nationals your checked in prologue so in my case after that i go back to the pits put in a spare wheel all my tools,jack, put 140 litres of fuel in which should add about 250 kgs and don't drive it like a madman then do about 450 kms without wringing its neck (Does anyone see my point). So should we all take up sailing or lawn bowls no noise there. A sport run by too many old people i guess.

tine · Rehab Dropout...

i dont understand it,maybe at a stadium in the middle of suburbia you dont want to upset the neighbour's,but where we race in the boonies,people are there because of the noise,why would you take that away,stupid.

heyu · Patron, 2013 AORC CHAMPION TIPSTER

This year the cars at Milbrodale seemed to be a lot quieter than they usually are. I thought it was great, you could still hear horsepower but not the shrill earpiecing stuff.
We already supply the guys on the starting line and surrounds with earplugs,but it is still sometimes painfull. yeah! I know, I'm old and this means I'm just about deaf anyway, but I would like to keep a little of what I have left of it.
I know, maybe we'll get some more younger folk trained up to take over these positions , cause they'll be able to stand the noise. Now , that's a thought!

Oh! sorry about being old.

-- Edited by heyu on Thursday 30th of August 2012 12:29:45 AM

LittleOttey112 · Powerhouse Poster

Why don't they have noise limits on V8 supercars?? Dad went to Townsville, a street circuit (through the streets of the city) for the V8s and ear plug sales went through the roof! We're racing in the middle of no where! Who goes to a freaking Off Road Event and complains about the noise. If it offends you that much, WHY THE HELL ARE YOU THERE!!!!!

simpson · Rehab Dropout...

Well said Lauren, the officials that are trying to enforce this wouldn't last five seconds in V8S and what would CAMS say. NOT a THING they know were there bread is buttered but some are intent on driving people out of our sport look at ORB with this noise thing a couple of years ago. ill pay for the earplugs if the can't afford some. Get rid of the wowsers.

jones off road · Rehab Dropout...

simpson wrote:
How does it work i go to National event my car's to loud, I go to a State run event no problem,at the MMC we took our own noise testing equipment guess what even at the rev cut it was under 95 db.
Rules say 30 mts from the car and test should be at 3000 rpm. At Nationals your checked in prologue so in my case after that i go back to the pits put in a spare wheel all my tools,jack, put 140 litres of fuel in which should add about 250 kgs and don't drive it like a madman then do about 450 kms without wringing its neck (Does anyone see my point). So should we all take up sailing or lawn bowls no noise there. A sport run by too many old people i guess.

Funny you say that....my workshop is approx 300mtrs from the bowling club, and the clinks of the bowls hitting the jack is soooo annoying! I have approached the EPA about the subject and they are looking into it. They have suggested also that the beer glasses should be plastic so while they 'cheer' each other I can still talk on the phone. Noise testing has shown that the fuller the beer glass the quieter they are, but as they empty I have found that the sandwich ladies voices seem to get louder.

As soon as I finish grinding and cutting, I take of my ear protection and all I can hear is the sprinklers still running on the greens.....something needs to be done!

Dont start me on sailing, we go waterskiing on a lake, when we stop for lunch, all you can hear is those sails flapping in the wind!

spoiltone · Rehab Dropout...

i kinda agree there ian, they dont need to be that loud . you can still get great power out of a well designed exhaust. that is quite.

simpson · Rehab Dropout...

My dyno guy might not agree, But the point i am trying to make is why the double standards. Remember when we had to stop useing Avgas and everyone else run it for a couple of years after we had to stop.

F1 or V8s in this country run events in city's so why can they get away with F1s around 120 db V8s around 112 db we on the other hand are mostly out in the middle of nowhere for National events and from what i can gather half a db won't be tolerated from now on, all three are sanctioned by Cams.

Nothing wrong with being old Ian as long as you don't start saying your bumb then you might have gone too far !

tumbleweed · Forum Junkie

Few other things that need attention before noise I think.

simpson · Rehab Dropout...

Jeremy why not put up your list of whats wrong with the sport it's just a friendly little forum after all ,nothing we say here could possibly change anything could it ?

Patrol842 · Forum Addict

I know a thing or two about noise testing, If someone tries to ping you for half a dB let me know. Also the meter has to be calibrated for the current weather conditions, real meters come with a calibration source so you can account for barometric pressure, humidity and temperature. If they start waving some junk from Jaycar about politely ask them to get appropriate equipment and training on how to use it. Errors of greater than 5dB are the norm when you compare cheap junk to a real meter.
It's akin to measuring spark plug gaps with those plastic verniers - and you have no idea how to read verniers.

I have offered them some advice on the testing methodology but they haven't taken it on board.

simpson · Rehab Dropout...

Mate you have my vote to be the new tech adviser to Cams, i wouldn't mind seeing the names of the cars they ping for noise published this might stop some of the BS thats going on, how would you know that your not being singled out by some officials because they have a problem with you ?

jones off road · Rehab Dropout...

Because Simpson, they do have a problem with you.......plus your car is really loud., and it's orange!

simpson · Rehab Dropout...

Don't go picking on the colour of my car Jones and did you sell your loud piece of junk yet ?

toby · Forum Addict

Up ya Gary! How was ya trip!

simpson · Rehab Dropout...

Hay Toby,yeah good we had a race home with Gerald in his Isuzu, no match for my Nissan UD we had some laughs,got home Mon arvo.

toby · Forum Addict

Haha sound like fun! We got home yesty arv was good! Lots of kms!

Patrol842 · Forum Addict

Cheers Simpson, I wouldn't be good at it though, I tend to rub people the wrong way without meaning to and I have no formal engineering qualifications. I have WAY too much to learn still. Besides, I'd increase the diesel engine capacity limit to 8.3 litres forced induction if I was in that job just to level the playing field.

The trick with noise testing is to continually sound your 146dB-A train horn to drown the engine noise out, problem solved. :)

for the record I do appreciate their intent, but the testing methodology is too prone to error and misinterpretation. Then there's the anti-lag on the Kittle cars which would otherwise easily pass, now you cant go and ban anti-lag or penalise someone for backfiring so the simplest way to shut cars up is a specific muddler type for non-turbo vehicles. Then again the induction noise from a multi throttle v8 would just about beat their noise limit.

-- Edited by Patrol842 on Thursday 13th of September 2012 04:32:21 PM

tumbleweed · Forum Junkie

simpson wrote:
I beleive i too rub people the wrong way without trying too hard, there is a problem with there process my car and another were tested at Sealake and Gundy both cars got 5 db louder from Sealake to Gundy with both of us not making any changes, the next event for me was MMC we took our own test meter and its under 95 db,even though it was told it was tested with a reading of 99db at Gundy someone is playing games i think,

That is the exact issue right there.

To start with a change in decibel rating of 3db is approximately doubling the 'strength' of the sound (decibels are a logarithmic scale) So your 5db louder is at least 3 times the sound pressure of Gundy.

How do you now go back to the workshop and spend time and money 'fixing' the problem so the ..........(insert whoever is unhappy with the noise here)................ are happy. Some new exhaust systems and the resultant Dyno tune will cost big $ and you cannot test it to the seemingly fluctuating meter that they are using.

I beleive we need to sort the methodology out before we go anywhere near penalising anyone otherwise the shtfite wll be massive.

We had a Noise monitoring organisation monitor the noise at a short course track a few years back. we had two car starts and the meter (I am talking proper meter here) mounted 15m from centre of the track. We had a couple of loud cars that night and the meter was 25m ahead of the start line (read full accelaration). The highest readings we were getting were 102db peak. Now the noise consultant told me that at that proximity a 10m distance difference would translate to around 3db (half) of the noise. The track is about 12-15m wide so the meter was approx 8m from the edge of the track. Take it to 30m and you are looking at around 6db less = 96db with TWO CARS accellerating off the line. We also had a hayabusa powered mini buggy run on its own and it only registered 100db and we all know how piercing a biek engine at 12000rpm can be.

If the limit is 95db fine but in my opinion we need to test it properly against what happens at a given race. gather the data, compare it against the meter we are trying to use, test at the exact same time how loud it is for the start marshall, the spectators and even the cows in the paddock 200m away. Then we have real information to base our decisions on and move forward. Our testing included two monitoring stations - one at the track and one 300m away at a residents house (incidently they had peaks of 74db) and Cost us $1500 for them to travel to the track set up the devices, return after the event and pick them up and write a report.

-- Edited by tumbleweed on Thursday 13th of September 2012 10:55:45 PM

simpson · Rehab Dropout...

I beleive i too rub people the wrong way without trying too hard, there is a problem with there process my car and another were tested at Sealake and Gundy both cars got 5 db louder from Sealake to Gundy with both of us not making any changes, the next event for me was MMC we took our own test meter and its under 95 db,even though it was told it was tested with a reading of 99db at Gundy someone is playing games i think,

Wolf · Rehab Dropout...

How does it get louder? Ahhh... probably the nav screaming....

jones off road · Rehab Dropout...

simpson wrote:
I beleive i too rub people the wrong way without trying too hard, there is a problem with there process my car and another were tested at Sealake and Gundy both cars got 5 db louder from Sealake to Gundy with both of us not making any changes, the next event for me was MMC we took our own test meter and its under 95 db,even though it was told it was tested with a reading of 99db at Gundy someone is playing games i think,

rubbing people the wrong way is always a problem, but I will always support you Simpson!

Do you think a Trophy kart will be too noisey?

Patrol842 · Forum Addict

So there you go.. now if your track is 6m wide, some cars have the exhaust on the left, some on the right and some out the back If you measure 20m from the centreline of the track the exhaust outlet can be anywhere between 17m and 23m from the microphone which is greater than 25% variation in distance. I believe their initial idea was 15 metres from the track so the error would have been larger.
If you've ever lived near an airport or a 24 hour freight yard you'll know that long range propagation of the sound is very variable with weather.

The human ear is logarithmic in its sensitivity, it takes 10db which is 10 times the energy to "appear" to be twice as loud. The real difference in your different readings of 95 and 99 is actually bugger all in apparent loudness.
general rule of thumb - every 3dB is doubled and every 10db = 10x. so 6dB = 4x and 20dB = 100x and 13dB = 20x of the actual pressure increase in the sound waves in PSI or whatever units you prefer.

The only fair way to measure is from both sides of the track at a probable spectator distance and average the reading. this will account for exhaust outlet direction and position in relation to the microphones.
Now if their basis for this rule is hearing protection then there are weightings for time, their argument is in fairly shaky ground.
http://www.worksafe.vic.gov.au/safety-and-prevention/health-and-safety-topics/noise/how-to-comply/find
"The noise level in a workplace is considered harmful to health if it exceeds the exposure standard, which refers to an average noise level of 85 decibels (A-weighted) over an eight-hour period, "
AVERAGE.... over EIGHT HOURS!
I've had to work on towers which had sirens so loud it would regularly kill parrots it was 20dB louder than a jet engine (that 20dB is 10x10 =100 times the pressure level). Because it was an evacuation siren we could not isolate it when working nearby, so the safety boffins calculated that we could wear earplugs and earmuffs and even if it sounded right next to us we were still within worksafe limits for our 8 hour day because we would only be exposed for the 30 seconds it took to climb down off the tower and the resultant level from the double hearing protection was below the damage threshold.
Even the flag marshall on the line wouldnt get close to their occupational limit with 80 cars and 30 second start intervals.

So they need to lift the limit to the damage threshold and ensure the people who spend any considerable time inside the spectator distance of many cars all day (the officials on the start line) wear hearing protection.

What I want to know is if they are so big on noise why are exhaust outlets only allowed to face rearward or sideways? An upward facing exhaust would be a pain in the ass with rain but would guarantee the exhaust is facing away from people.

Buggy924 · Powerhouse Poster

There was noise testing at the Yea 150 on the week end. Alas I have been log booked for excessive noise. My motor is a Nissan SR20 turbo with a 12 inch exhaust pipe (same exhaust system as most others are running). Out of the 20 buggies, I think half were pinged. They tested us during prologue and I was short shifting through the gears as I was having break issues. I did not compete in any of the heats as I withdrew after the prologue. I was handed my Log book back and then asked to hand it back the next day so they could write the noise reading into it after signing it off previously.

I now have to try and rectify the noise issue for the next event.

simpson · Rehab Dropout...

A couple of questions who conducted the testing , were the cars that loud for half to be reported for excessive noise because you must have been a spectator for the rest of the event so what's your opinion.

Buggy924 · Powerhouse Poster

Morrie Williams (CAMS Chief Scruiteneer)conducted the test with a hand held device. There were some of the buggies that were way too loud when they hit their rev limiter but I do not actually know where he stood for the testing as I was not watching out for him. They informed us at the driver's breifing to check our log book when we received them back. Morrie went around the pits and informed every one of their reading he detected even if you passed which was good as those people who just made it below the 95db level could also look at addressing the level to ensure that they did not get pinged next time. I beleive that some of the buggies that were loud but might have passed due to the pitch of the sound ( a drone not a high pitch). There was about four plus class 8 vehicles there and I think they all passed.

Magila · Forum Addict

I helped with recovery on the weekend at the Highlands 150 , we could see a shed in the distance on the property next door maybe 40 or 50 metres away, the farmer/property owner was working on his shed all day not once did he take any notice of the action on our side of the fence.

Now some of you may find this hard to believe, but, I don't think this guy likes off road racing at all, what if he decides he's had enough of the dust and noise on the other side of the fence and complains to the council, Do you really think they are going to care about the logarithmic sensitivity of a European swallow, all they are going to care about is if we have something in place to regulate our noise and we meet some sort of guide lines.

Don't get me wrong guy's I love the sound of a twin turboed V6 with anti lag as much as the next motorsports fan, But after the weekend I can see where they are going with this one, we are all racing in somebody's back yard and no matter how big the property there's usually a neighbour.

Rather than can the idea of noise testing and the whole process involved in taking the readings why not push to increase the limit ?
who came up with 95db anyway.

just my thoughts I'm probably going to cop it from both sides now

spoiltone · Rehab Dropout...

why not run the limits with a certain critera?

like a car reading
say 95db at 10mtr on a 45degree angle at approx 4000rpm. and leave it like that.

consitent then for all cars etc etc

and no confusion.
not saying use them numbers but something like that.
if it good enought o be used in the street, and citys etc surely we can adopt something similar with a set critera for checking.

RedMist · Forum Junkie

Wild. I hope that this type of regulation never approaches NZ shores. Aren't we trying to put on a show? The most extreme motorsport there is? If so then shouldn't we sound extreme?