2008 IMPBA INTERNATS
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Grimracer
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Hi mikey,
What a month so far..
As fate would have some of the players in making this happen have some how all set there vacations or out of town work schedules at the same time.
I was in Las Vegas
Garrett in CA
Russ in FL
Ron in GA
Whew... the good news is most of that is over and with the spring nats under our belts its time to get back to work..
OK..
We also have a meeting this week to talk about any last minuet art work for shirts and what not.. we have a race next weekend in WI that most of us are attending to get some of the last details underway.
We have entries coming in and we are making good head way on signage as well as banners and sponsors (WE ALWAYS NEED MORE..) Would any of the districts like to sponsor a class? That would be cool..
As soon as we have more info we will update the website
Thanks guys and LETS GET THOSE ENTRIES IN
Grim
What a month so far..
As fate would have some of the players in making this happen have some how all set there vacations or out of town work schedules at the same time.
I was in Las Vegas
Garrett in CA
Russ in FL
Ron in GA
Whew... the good news is most of that is over and with the spring nats under our belts its time to get back to work..
OK..
We also have a meeting this week to talk about any last minuet art work for shirts and what not.. we have a race next weekend in WI that most of us are attending to get some of the last details underway.
We have entries coming in and we are making good head way on signage as well as banners and sponsors (WE ALWAYS NEED MORE..) Would any of the districts like to sponsor a class? That would be cool..
As soon as we have more info we will update the website
Thanks guys and LETS GET THOSE ENTRIES IN
Grim
Grimracer
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- Joined
- Dec 27, 2001
- Messages
- 9,518
2008 Interants Racers,
Things are shaping up quite well for this years event.
We have secured a safe radio impound trailer
We have the food for the banquette selected
We have a great sponsor for the hot pits, give Wesley’s Custom Graphics a huge attaboy!
O yea.. Al’s has also jumped in to help out.. thanks Cindy and the gang at Al’s
We are still looking for more sponsorship for some of the classes.. thanks to those of you that have already done so.
Make sure you check back here for more info. Also make sure you keep checking www.internats08.com for any updates or information.
I have been getting a few questions about how we are going to handle 2.4 radio systems.. Well we aren’t… O I don’t mean at all, but we REALY have no need to worry about this type of modulation in the least.. and to take a TRUE step forward in our hobby we are NOT going to impound the 2.4 radios. You will however be required to have a bight orange clip (supplied by dist 4) on your radio to avoid causing any confusion to our long antenna counterparts. Its time to start taking advantage of what 2.4 has to offer not just the racer but the race organizers / club as well.. (less radios in the impound the eraser it is going to be to keep track of the ones we do have to care for).. also.. I like this because it take a lot of the (oops we dropped a radio or you forgot your radio in the trailer and it locked up for the night scenario).. 2.4 ENDS ALL OF THAT.. its your radio.. its your event..
Remember you can register on line or by downloading the hard copy and sending it in off the IMPBA website www.impba.net
I will have the after hours activities up and posted in the next week or so.. also for those of you that might like a warm up on the internts race water remember this coming weekend the river city club is hosting there spring race..
See ya this weekend in EVILLE
Grimracer
Things are shaping up quite well for this years event.
We have secured a safe radio impound trailer
We have the food for the banquette selected
We have a great sponsor for the hot pits, give Wesley’s Custom Graphics a huge attaboy!
O yea.. Al’s has also jumped in to help out.. thanks Cindy and the gang at Al’s
We are still looking for more sponsorship for some of the classes.. thanks to those of you that have already done so.
Make sure you check back here for more info. Also make sure you keep checking www.internats08.com for any updates or information.
I have been getting a few questions about how we are going to handle 2.4 radio systems.. Well we aren’t… O I don’t mean at all, but we REALY have no need to worry about this type of modulation in the least.. and to take a TRUE step forward in our hobby we are NOT going to impound the 2.4 radios. You will however be required to have a bight orange clip (supplied by dist 4) on your radio to avoid causing any confusion to our long antenna counterparts. Its time to start taking advantage of what 2.4 has to offer not just the racer but the race organizers / club as well.. (less radios in the impound the eraser it is going to be to keep track of the ones we do have to care for).. also.. I like this because it take a lot of the (oops we dropped a radio or you forgot your radio in the trailer and it locked up for the night scenario).. 2.4 ENDS ALL OF THAT.. its your radio.. its your event..
Remember you can register on line or by downloading the hard copy and sending it in off the IMPBA website www.impba.net
I will have the after hours activities up and posted in the next week or so.. also for those of you that might like a warm up on the internts race water remember this coming weekend the river city club is hosting there spring race..
See ya this weekend in EVILLE
Grimracer
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Grimracer
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- Dec 27, 2001
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IMPBA racers,
I have been getting a few PMs from IMPBA racers concerned about how we are going to handle the noise rule at the 2008 internats. Its simple we are going to follow the rule book.
We do however have some testing to do to better understand what happed in 06. From what I have been told, boats (not sure they were the same boats) were not over the DB limit at the race just weeks before the interants and then, “boats” , again not sure they were the same boats were over the limit just a few weeks later. I did not see this myself as I was not at the race that was just a few weeks before. Some people are (rumor has it) not going to attend (or might not attend) the race because of this issue.
I will be at the internats pond this weekend trying to gain a better understanding of what might be going on or might have happened in 06.
If you are on the fence about attending the race because of this issuer I will “should” be able to report on my findings mid next week.
Mike Z
I have been getting a few PMs from IMPBA racers concerned about how we are going to handle the noise rule at the 2008 internats. Its simple we are going to follow the rule book.
We do however have some testing to do to better understand what happed in 06. From what I have been told, boats (not sure they were the same boats) were not over the DB limit at the race just weeks before the interants and then, “boats” , again not sure they were the same boats were over the limit just a few weeks later. I did not see this myself as I was not at the race that was just a few weeks before. Some people are (rumor has it) not going to attend (or might not attend) the race because of this issue.
I will be at the internats pond this weekend trying to gain a better understanding of what might be going on or might have happened in 06.
If you are on the fence about attending the race because of this issuer I will “should” be able to report on my findings mid next week.
Mike Z
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Darin Jordan
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- 1,821
Mike,
When I was racing with the SCCA (sportscar racing), we used to have varying sound readings from race to race... placement of the meter and weather conditions REALLY play a big factor in how the meter reads... Cloudy and cooler days use to result in a higher meter reading. Also, larger bore motors, which were actually "quieter" to the ear, would spike the meter more than high-winding "loud" motors that would otherwise bother the human ear... For example, our 1977 Trans-Am SuperProduction car, running a 455 Pontiac motor, would push the meter over 104... but a Mazda rotary spinning 10,000 RPM would be under 100... even though you'd need earplugs around the rotary...
Around water, you may also have differing effects on the readings as the sound bounces off the surface and any waves that exist... or concrete sides, rocks, etc...
I think special attention to the details of meter placement are going to be really important to maintain a consistant read...
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- Jul 24, 2002
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- 7,133
Might want to look at not putting the meter on the side walk, AMA has different rules when testing on grass or pavement.
ps: Thanks for all the hard work!
Grimracer
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- Dec 27, 2001
- Messages
- 9,518
Darin
I will be taking note of the surrounding conditions and hopefully coming to some kind of a tolerance for the reading. Im sure I can repeat the location distance from buoy 6, height and what not to a T. If we have variables will likely be the weather, thanks for your input. I have two test sessions at the pond before the big show. Im confident we are going to be able to draw some conclusions. I can just imagine air density taking its toll on my readings.
Jerry.. The F mono GONE.. we were looking forward to the entertainment. O well we will have to wait until the I waters party for that. See ya soon bud.
Grimracer
I will be taking note of the surrounding conditions and hopefully coming to some kind of a tolerance for the reading. Im sure I can repeat the location distance from buoy 6, height and what not to a T. If we have variables will likely be the weather, thanks for your input. I have two test sessions at the pond before the big show. Im confident we are going to be able to draw some conclusions. I can just imagine air density taking its toll on my readings.
Jerry.. The F mono GONE.. we were looking forward to the entertainment. O well we will have to wait until the I waters party for that. See ya soon bud.
Grimracer
Grimracer
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- Dec 27, 2001
- Messages
- 9,518
UPDATE.. Check it out racers
2008 Internats Club Shirt Day
Rally together and wear your club shirt proudly.
July 20 and 21st are CLUB SHIRT DAYS. Wear your club shirt proudly; the points you win in your heats count towards winning cool prizes.
Rules
Clubs need to be Registered IMPBA clubs
If you belong to more then one club you can only collect points for one club.
You must wear your screen printed or embroidered club shirt to participate (no permanent marker or home made shirts allowed)
All points acquired from your racing classes will count towards your club total regardless of how many classes you are running on that day
Club with the most racing points is declared the winner.
Award presented at the banquet
HAVE FUN
Grimracer
2008 Internats Club Shirt Day
Rally together and wear your club shirt proudly.
July 20 and 21st are CLUB SHIRT DAYS. Wear your club shirt proudly; the points you win in your heats count towards winning cool prizes.
Rules
Clubs need to be Registered IMPBA clubs
If you belong to more then one club you can only collect points for one club.
You must wear your screen printed or embroidered club shirt to participate (no permanent marker or home made shirts allowed)
All points acquired from your racing classes will count towards your club total regardless of how many classes you are running on that day
Club with the most racing points is declared the winner.
Award presented at the banquet
HAVE FUN
Grimracer
Grimracer
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- Joined
- Dec 27, 2001
- Messages
- 9,518
Here we go...
Sound test results for the 2008 Internats
I did a bunch of DB testing at Eagle Crest Lake this last weekend during the Evansville Spring Shootout. I think it is important to note that both small motor classes as well as large motor classes were running at this event.
The reason for this test was to verify if or if not Eagle Crest Lake and its surrounding is to blame for high sound levels regarding RC boating activities. It was also to determine if any type of left side shielding would aid in controlling sound.
The meter I used is made an Extech 407735, link to the meter. http://www.extech.com/instrument/products/...450/407735.html
I could not find my tripod (true) and had to go to plan B as far as setup. Plan B is the same system we use here at work for our sound testing and so it made sense to me to follow that. We place the meter towards the end of the table to aid in controlling any reflective sound from the water. It also allows us to adjust the sound level in relation to the boats position on the pond. Read on.
Some Details of the setup:
Settings:
Range HI
Response F
Funct A
Meter was set 25’ from the shore line and 5’ feet to the left alignment of buoys 4 and 6.
The meter was set 32” from the ground on a 4’ long card table 2’ wide. The meter was set to the full aft end of the table on a length of dense foam rubber. The table was positioned such that when sighting down the meter one would start to see water about 20’ before buoy 6 came into view (lane 8 or so). Having the meter to the rear of the table allows us to help cancel any reflective sound from the water as well as helping to reduce the capture pressure from a boat that has made a very close pass.
I had no tent near me and or other obstruction. There was a small tree to my left about 15’ away but no other hard or sound capturing media in the area.
I also (per recommendation) brought along a sound shield. My sound shield was a 2” thick 4’X6’ chunk of blue foam board. I did not have a “sound box” and so I did not test with that system.
I tested all three days I was at the pond and we had a variety of wind conditions.
Results from Friday
70deg
N/W winds 12 to 15
Typical surrounding sound was 65db av
During testing on Friday the highest DB recorded was 87db. It was scale boat. Typical db readings throughout the day were in the 83-85db range. To start to gain some info on what shielding might or might not do I placed a note pad in front of the meter to gain some idea of how much drop I might see. Typical was a drop of 3db (one would expect to see a drop) with the shield in front of the meter. Placing the note book to the side, left or right made no difference in the sound levels the meter was seeing. With the boats on the water the same thing was witnessed. Having the note book shield in front of the meter did drop the db but having it to either side did noting to dampen the sound levels.
Results from Sat
68deg
S/W winds at 20 some swirling
Typical surrounding sound was 62db av
The highest db recorded on Saturday as a 91. The 91 was in “open class” mono. Typical db reading throughout the day were in the 84-87db range. During Saturdays testing I placed the large sound shield to the left of the meter. I was told that part of the issue with recording sound at a RC boat race is the way the exhaust points at the location of the meter as the boat passes down the front straightaway. The assumption was that the exit of the exhaust pointing the direction of the location of the meter could be causing higher DB readings then as if the boat was passing perpendicular to the meter. Placing the sound shield to the left of the meter had NO effect on the readinngs.. This was tried numerous times with no change in the readings.
Sundays Testing
73deg
W/N/W winds 15 to 20
Typical surrounding sound was 63db av
The highest db recorded on this day was 93. It was done with an open (F) class hydro. Typical readings were in the 84-87 range.
More notes:
I did place the protective foam material from the meter box to keep the wind off the pickup.
If two or more boats were side by side passing the meter no notes were made regarding that pass.
Conclusion;
After spending 3 days doing sound testing at Eagle Crest Lake in Evansville IN I feel if a boat is over the 92db limit the boat is at fault and not the position or placement of the meter. Any attempt at shielding the meter from the left is not effective enough to make ANY difference in the reading from the boat to the meter. (This was witnessed by more then just me)
Note: It was interesting to observe that boats with different pitches were seemingly louder then others. The meter itself tells a different story.
I will try to post some pictures of this setup as soon as I can to this post.
Grimracer
Please let me know if you see any issues with this report.. thanks.
Sound test results for the 2008 Internats
I did a bunch of DB testing at Eagle Crest Lake this last weekend during the Evansville Spring Shootout. I think it is important to note that both small motor classes as well as large motor classes were running at this event.
The reason for this test was to verify if or if not Eagle Crest Lake and its surrounding is to blame for high sound levels regarding RC boating activities. It was also to determine if any type of left side shielding would aid in controlling sound.
The meter I used is made an Extech 407735, link to the meter. http://www.extech.com/instrument/products/...450/407735.html
I could not find my tripod (true) and had to go to plan B as far as setup. Plan B is the same system we use here at work for our sound testing and so it made sense to me to follow that. We place the meter towards the end of the table to aid in controlling any reflective sound from the water. It also allows us to adjust the sound level in relation to the boats position on the pond. Read on.
Some Details of the setup:
Settings:
Range HI
Response F
Funct A
Meter was set 25’ from the shore line and 5’ feet to the left alignment of buoys 4 and 6.
The meter was set 32” from the ground on a 4’ long card table 2’ wide. The meter was set to the full aft end of the table on a length of dense foam rubber. The table was positioned such that when sighting down the meter one would start to see water about 20’ before buoy 6 came into view (lane 8 or so). Having the meter to the rear of the table allows us to help cancel any reflective sound from the water as well as helping to reduce the capture pressure from a boat that has made a very close pass.
I had no tent near me and or other obstruction. There was a small tree to my left about 15’ away but no other hard or sound capturing media in the area.
I also (per recommendation) brought along a sound shield. My sound shield was a 2” thick 4’X6’ chunk of blue foam board. I did not have a “sound box” and so I did not test with that system.
I tested all three days I was at the pond and we had a variety of wind conditions.
Results from Friday
70deg
N/W winds 12 to 15
Typical surrounding sound was 65db av
During testing on Friday the highest DB recorded was 87db. It was scale boat. Typical db readings throughout the day were in the 83-85db range. To start to gain some info on what shielding might or might not do I placed a note pad in front of the meter to gain some idea of how much drop I might see. Typical was a drop of 3db (one would expect to see a drop) with the shield in front of the meter. Placing the note book to the side, left or right made no difference in the sound levels the meter was seeing. With the boats on the water the same thing was witnessed. Having the note book shield in front of the meter did drop the db but having it to either side did noting to dampen the sound levels.
Results from Sat
68deg
S/W winds at 20 some swirling
Typical surrounding sound was 62db av
The highest db recorded on Saturday as a 91. The 91 was in “open class” mono. Typical db reading throughout the day were in the 84-87db range. During Saturdays testing I placed the large sound shield to the left of the meter. I was told that part of the issue with recording sound at a RC boat race is the way the exhaust points at the location of the meter as the boat passes down the front straightaway. The assumption was that the exit of the exhaust pointing the direction of the location of the meter could be causing higher DB readings then as if the boat was passing perpendicular to the meter. Placing the sound shield to the left of the meter had NO effect on the readinngs.. This was tried numerous times with no change in the readings.
Sundays Testing
73deg
W/N/W winds 15 to 20
Typical surrounding sound was 63db av
The highest db recorded on this day was 93. It was done with an open (F) class hydro. Typical readings were in the 84-87 range.
More notes:
I did place the protective foam material from the meter box to keep the wind off the pickup.
If two or more boats were side by side passing the meter no notes were made regarding that pass.
Conclusion;
After spending 3 days doing sound testing at Eagle Crest Lake in Evansville IN I feel if a boat is over the 92db limit the boat is at fault and not the position or placement of the meter. Any attempt at shielding the meter from the left is not effective enough to make ANY difference in the reading from the boat to the meter. (This was witnessed by more then just me)
Note: It was interesting to observe that boats with different pitches were seemingly louder then others. The meter itself tells a different story.
I will try to post some pictures of this setup as soon as I can to this post.
Grimracer
Please let me know if you see any issues with this report.. thanks.
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Tony Jacuzzi
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- Jun 26, 2002
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- 1,789
Great info Mike . Your study is really going to be a "Mythbuster" for sure... Way to go .. Tony J
SayMikey
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- Feb 23, 2003
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2. All boats over the 92db limit shall be advised of being over. A boat found in violation ofthe 92db limit by at least 1 (one) db or more will be issued a technical warning for that
heat. If upon subsequent heats the boat continues to exceed the db limit by at least 1
(one) db or more it will be awarded last (9 th) place points (40 points) regardless of it's
finish if said boat completes the heat or heats in question. A DNF will still result in 25
point score and a DNS remains 0 points. At all IMPBA timed events including the
International Regatta Straightaway and Oval Trophy Trials any boat exceeding the 92
dB limit by 1 (one) dB or more will not receive a time for any pass attempt that the boat
was found over the limit, all other passes at or under the limit will count.
Brian Schymik
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- Nov 24, 2002
- Messages
- 773
If two or more boats were side by side passing the meter no notes were made regarding that pass.
Quoted by Grimracer.....
This is important. Two boats in front of a meter at a time. The meter does NOT show the loudest reading... it DOES show an additive reading that is a pure mathematical formula, that is in all of the science books. Boats have to be the only one in front of the meter.
Brian
Quoted by Grimracer.....
This is important. Two boats in front of a meter at a time. The meter does NOT show the loudest reading... it DOES show an additive reading that is a pure mathematical formula, that is in all of the science books. Boats have to be the only one in front of the meter.
Brian
Mark Bullard
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- Jan 26, 2004
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- 1,781
Ok Grim, that sounds like you did some homework. Question, did you say the the meter was placed in the middle of a 4' long 2'wide table with the placement being to the rear part of the table? Was the table set long ways to the lake or the other? You also said that you did not check or note I should say two boats together. What will be the out come of Multi-Engine class in this event. Ambient levels will go up all over the lake with this class. With the average being 12 instead of 6 engines.
Mark
Mark
Grimracer
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- Dec 27, 2001
- Messages
- 9,518
Mark,
First and foremost we are looking forward to having you make the trip to the race this year. Thanks for your questions.
The meter was mounted towards the back of the table with the tables length parallel with the meter. So.. that being said there was about 3' of table below and in front of the meter.
I hope to get some pics on here of the way it was setup.
No twins were at the race. I hope to gain some information at the June race regarding twins. Twins are way cool to watch.
Brute power
Pure Speed
And that awesome twin sound
We look forward to having them put on a great show in 08.
Grimracer
First and foremost we are looking forward to having you make the trip to the race this year. Thanks for your questions.
The meter was mounted towards the back of the table with the tables length parallel with the meter. So.. that being said there was about 3' of table below and in front of the meter.
I hope to get some pics on here of the way it was setup.
No twins were at the race. I hope to gain some information at the June race regarding twins. Twins are way cool to watch.
Brute power
Pure Speed
And that awesome twin sound
We look forward to having them put on a great show in 08.
Grimracer
Mark Bullard
Well-Known Member
- Joined
- Jan 26, 2004
- Messages
- 1,781
Grim,
Based on your readings that there was a 20% failure rate on the big boats (80's and above). That is if I did my math right and also if the 19 boats that ran in open mono, hydro, and twin were all big motor boats. If not then the percentage failure rate would be higher. The db readings overall are higher compared to other lakes in IMPBA by about 5 to 10 db. Also this site has gotten worst since the last Internats with the new Cheese Burger place that has been completed. But this site is still one of the best sites we have in IMPBA.
Now Brian made a statement about additive reading of multi engines passing the meter being a pure mathematical formula, that is in all of the science books. He is right on that one. A boat that is at about 90db will be about 93db with two engines. The problem that I am seeing is all of the big motor classes. The 80 and above motors are the biggest air pumps that we run nitro thru and create the biggest pressure or sound wave.
The db meter is more of a pressure meter than a frequency meter. And sound is a pressure wave but there is also frequency to think about also. This is why the boats that sounded louder than other boats were not making as much of a pressure wave as other boats. But the boat sounded louder because of the frequency of the pressure wave or sound. Therefore the db reading was lower.
Now with all of this said the db meters have a +/-2 db tolerance based on ANSA standards. The human ear is only tested with 5db increments because only a real good ear can make the differance between a 3db change and it would be hard to make that out every time.
You have a lot of good information on this lake. It will be very hard for a good running big block motor to pass at this lake. Some motors will be worst than others with different pipes and boats. And to tell the truth I do not know what my boat does right now. Different motors and pipes from what I ran at the last Internats there. I will be there in June along with a lot of other mutli engine boats and big block boats. I guess we will see what we can see then.
Mark
Based on your readings that there was a 20% failure rate on the big boats (80's and above). That is if I did my math right and also if the 19 boats that ran in open mono, hydro, and twin were all big motor boats. If not then the percentage failure rate would be higher. The db readings overall are higher compared to other lakes in IMPBA by about 5 to 10 db. Also this site has gotten worst since the last Internats with the new Cheese Burger place that has been completed. But this site is still one of the best sites we have in IMPBA.
Now Brian made a statement about additive reading of multi engines passing the meter being a pure mathematical formula, that is in all of the science books. He is right on that one. A boat that is at about 90db will be about 93db with two engines. The problem that I am seeing is all of the big motor classes. The 80 and above motors are the biggest air pumps that we run nitro thru and create the biggest pressure or sound wave.
The db meter is more of a pressure meter than a frequency meter. And sound is a pressure wave but there is also frequency to think about also. This is why the boats that sounded louder than other boats were not making as much of a pressure wave as other boats. But the boat sounded louder because of the frequency of the pressure wave or sound. Therefore the db reading was lower.
Now with all of this said the db meters have a +/-2 db tolerance based on ANSA standards. The human ear is only tested with 5db increments because only a real good ear can make the differance between a 3db change and it would be hard to make that out every time.
You have a lot of good information on this lake. It will be very hard for a good running big block motor to pass at this lake. Some motors will be worst than others with different pipes and boats. And to tell the truth I do not know what my boat does right now. Different motors and pipes from what I ran at the last Internats there. I will be there in June along with a lot of other mutli engine boats and big block boats. I guess we will see what we can see then.
Mark
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