Don Pisto Posted January 23, 2007 Share Posted January 23, 2007 I'll be goin to my first car audio competition this Saturday. I have an '01 Accord sedan and I have no clue as to what frequency to play, although just by ear I'll probably start off with a 50 Hz tone. I know more than likely that first shot is usually the loudest so I was wondering if anyone knows the resonant frequency (approx) for an '01 Accord sedan. Or even one for similar generation vehicles would be great, or even if someone knows where I can find out that info. I would greatly appreciate any help. Thanks in advance Link to comment Share on other sites More sharing options...
xer0 Posted January 23, 2007 Share Posted January 23, 2007 i don't kno about for the entire car but i thought only one malarial ( ie. aluminum, steel, plastic,glass) can resonate at a time Link to comment Share on other sites More sharing options...
Don Pisto Posted January 24, 2007 Author Share Posted January 24, 2007 The cab itself has a frequency at which it peaks at. I know it would have been better to find this out before building my enclosure so I can fine tune it to that. But finding the res. freq. of the cab will help to determine what frequency will get the loudest on a dB meter. I've done some searching on caraudio.com and finding the RF involves tools that are expensive and what not. It's not really important or crucial to find the RF, I was really just curious and it would help slightly instead of goin in completely blind just doing trial and error runs. Link to comment Share on other sites More sharing options...
xer0 Posted January 24, 2007 Share Posted January 24, 2007 but only one material in the cab would resonate at a frequency. i have used some of that equipment at my test lab job:-p edit: so find out what the cable si mostly made of and find the residence frequency of that material. that is my educated ges Link to comment Share on other sites More sharing options...
cranny Posted January 24, 2007 Share Posted January 24, 2007 for competition , we used to use a bass drop. it started at like 125hz , and ended on 45hz i beleve. bzzzzzzzzzzzz , lol. once it got down to its lowest note , like i said 45hz approx , it would stay there and pop every 2 seconds. i entered 3 competitions , and won 3 first places with it. wish i still had it id give it to you. we all used it with success. best i hit was 141.0 db even. 2 12" JLaudios(W1's this was like 10 years ago almost and W1's were new) , alpine mrv100 amp. its 400 nominal amp , i was running half it , subs hooked to amp stereo. so i was running half the amps capabilities , 100 nominal a sub. the reason being is i got a smokin deal on them , but they were 4 ohm subs not 8 ohm , meaning i couldnt bridge my amp and run it 2 ohms mono back than. still hit hard though. Link to comment Share on other sites More sharing options...
xer0 Posted January 24, 2007 Share Posted January 24, 2007 how do competition work, like they mark the peak DBs or what? Link to comment Share on other sites More sharing options...
cranny Posted January 24, 2007 Share Posted January 24, 2007 exactly , if its a db drag. theres also sound quality contests too. they put a SPL(sound pressure level) mic in the car , close to the windshield as they can get it , therefore as far away from the subs as possiblle , and you try and peak your highest db's. db drags consist of 2 cars going at once , sitting usually in front of what resembles a drag track xmas tree. a row of lights vertically , and the louder you are , the more lights light up. whoever , after a minute , has the most lights lit , wins. Link to comment Share on other sites More sharing options...
Don Pisto Posted January 24, 2007 Author Share Posted January 24, 2007 for competition , we used to use a bass drop. it started at like 125hz , and ended on 45hz i beleve. bzzzzzzzzzzzz , lol. once it got down to its lowest note , like i said 45hz approx , it would stay there and pop every 2 seconds. i entered 3 competitions , and won 3 first places with it. wish i still had it id give it to you. we all used it with success. best i hit was 141.0 db even. 2 12" JLaudios(W1's this was like 10 years ago almost and W1's were new) , alpine mrv100 amp. its 400 nominal amp , i was running half it , subs hooked to amp stereo. so i was running half the amps capabilities , 100 nominal a sub. the reason being is i got a smokin deal on them , but they were 4 ohm subs not 8 ohm , meaning i couldnt bridge my amp and run it 2 ohms mono back than. still hit hard though. Yeah I read somewhere partly about what you're talkin about...using a sweep. I'm hoping to hit at least a 142. I'm running a DD 9515 in 5 cu. ft. ported enclosure tuned to approx 35 Hz running off an RF Punch 500a2. Its only gettin 500w but its hitting damn nice. My other amp can't handle my pre-out voltage unfortunately and depending on how I wired that, i could either get 750w or 3000w. My goal is to break 150 dB once I get a powerful enough amp. Link to comment Share on other sites More sharing options...
Don Pisto Posted January 24, 2007 Author Share Posted January 24, 2007 exactly , if its a db drag. theres also sound quality contests too. they put a SPL(sound pressure level) mic in the car , close to the windshield as they can get it , therefore as far away from the subs as possiblle , and you try and peak your highest db's. db drags consist of 2 cars going at once , sitting usually in front of what resembles a drag track xmas tree. a row of lights vertically , and the louder you are , the more lights light up. whoever , after a minute , has the most lights lit , wins. Is it a minute? I checked the Term Pro website a few days ago and the dB Drag rules and it stated 30 seconds. xer0, if you would like more info on audio competitions visit www.termpro.com. There are several different mics you can get metered on, however the one's people accept as "legal" numbers, are from the new Term Lab. Other mic's are the Audiocontrol and previous versions of it. Basically, the Term Pro is more accurate while the others are off a few decibels. Mathematically speaking 3 dB = twice as loud. Link to comment Share on other sites More sharing options...
xer0 Posted January 24, 2007 Share Posted January 24, 2007 so that "bass drop" tries to hit all the frequencyies that would make the car resonate to gain more DBs? right xer0, if you would like more info on audio competitions visit www.termpro.com. i am to lazy to research right now from tryen to research for ppl more noobish then me Is it a minute? I checked the Term Pro website a few days ago and the dB Drag rules and it stated 30 seconds. dotn want to answer for cranny but didn't he say he was doing it 10 years ago? so might of changed Link to comment Share on other sites More sharing options...
Don Pisto Posted January 24, 2007 Author Share Posted January 24, 2007 so that "bass drop" tries to hit all the frequencyies that would make the car resonate to gain more DBs? righti am to lazy to research right now from tryen to research for ppl more noobish then me dotn want to answer for cranny but didn't he say he was doing it 10 years ago? so might of changed The bass drop or frequency sweep plays a frequencies that will help to find the resonant frequency that will help you to tune your enclosure to that RF. The better tuned the enclosure is to the vehicle, the louder in dB's it will be when you play the peak frequency. Its still something i'm tryin to grasp a concept of so what i said may be unclear. yeah I realized after my post he said 10 years ago so it would make sense that they changed it. Also they used a different mic then so if the same system was metered on the new TL it would have different results. THeres different classes and rules. The one I'll be goin into is Street B, which you are only allowed in the vehicle if you have ear protection, provided you hit higher than 140, otherwise you will be disqualified. Also in this class the vehicle must be turned off, so you lose about a couple volts give or take. Here is the actual rules to dB Drag. Its quite long so it'll take about 30 mins to read through all of it. Link to comment Share on other sites More sharing options...
xer0 Posted January 24, 2007 Share Posted January 24, 2007 it not the volts u worry about it the amps Link to comment Share on other sites More sharing options...
Don Pisto Posted January 24, 2007 Author Share Posted January 24, 2007 it not the volts u worry about it the amps I'd say its a bit of both. An amp will produce more power at higher voltages. For example: Orion 2500d does approx 3000w @ .5 ohms @ 13.8V I believe. At the same impedence and at 16V it will put out approx 4700w, and these are rms figures. But if you don't have the amperage then you're getting less of that power. I'll be fine since I have a 90A stock alt and I'm pulling no more than 55 amps with the amp I'm running, but if I were to use my 3k watt amp, then it's more like 300 amps and I definitely wont see 3000w. Link to comment Share on other sites More sharing options...
Unpredictableacts Posted January 24, 2007 Share Posted January 24, 2007 I did not read but the first couple of post...A BAS DROP or a "sweep" is a bad and easy way to use up your battery on useless notes you also need to have a ported tuned box and have a rough idea where it is tuned to.....then get a rough idea to where to sart you tones at. My box was tuned to 46 Hz but my sweet spot was 48-49Hz on the bass CD. I used a single battery set up and if you are doing the same it is VERY important to get an idea of your sweet spot before you .... embarass your self and discharge your battery and at the same time be out of $40 for entry fees. Link to comment Share on other sites More sharing options...
Don Pisto Posted January 24, 2007 Author Share Posted January 24, 2007 I did not read but the first couple of post...A BAS DROP or a "sweep" is a bad and easy way to use up your battery on useless notes you also need to have a ported tuned box and have a rough idea where it is tuned to.....then get a rough idea to where to sart you tones at. My box was tuned to 46 Hz but my sweet spot was 48-49Hz on the bass CD. I used a single battery set up and if you are doing the same it is VERY important to get an idea of your sweet spot before you ....embarass your self and discharge your battery and at the same time be out of $40 for entry fees. My enclosure is tuned to approx 35 Hz and luckily the comp is only $25. But how would I find a good estimate for the "sweet spot"? I know what may sound loud to the ear may not exactly be as loud on the mic. I just have a feeling I'm somewhere between 40 and 55 Hz, but I dont know exactly how to pin point it. I got some windshield flex already goin. If I were somehow to find which frequency gives me the most flex, would that help me determine the better frequency? Also, say if i'm doing trial and error playing with a few frequencies, would I do it in the same 30 second run or in another run? Link to comment Share on other sites More sharing options...
Unpredictableacts Posted January 24, 2007 Share Posted January 24, 2007 My enclosure is tuned to approx 35 Hz and luckily the comp is only $25. But how would I find a good estimate for the "sweet spot"? I know what may sound loud to the ear may not exactly be as loud on the mic. I just have a feeling I'm somewhere between 40 and 55 Hz, but I dont know exactly how to pin point it. I got some windshield flex already goin. If I were somehow to find which frequency gives me the most flex, would that help me determine the better frequency? Also, say if i'm doing trial and error playing with a few frequencies, would I do it in the same 30 second run or in another run? 35hz is more so a good everyday driving tune that is not something I would feel comfortable doing a comp with...if that is a case you need a box with interchanglable ports so you can be good listening at one point and competition ready with the other port....in your case and you box being tuned to 35hz all I can say is good luck......it is like you dragging a stock 4 banger 95 ford turaus against a top fueler, you are beat befor eht e green light even goes off. You will be running against guys that are 100% serious about this and now there system in and out and now how to gewt that extra .02 DB out of it.......I have done several big points events and it is a waste(but funny) to see a guy with a sealed box pull up case he thinks his bass is loud compared to kids at his school.......this is awhole other level of school and you need to be other competitiors questions if you are dead serious about this. Link to comment Share on other sites More sharing options...
Unpredictableacts Posted January 24, 2007 Share Posted January 24, 2007 USE the BURP method to conserve your battery it is like GOLD and you need to save it...30 secs it actually to long to give a person because most people will use the entire 30 secs to do nothing benefital except to drian their battery........start it at about 38 and work up the guy controlling the computer will be able to then tell you your sweet FREQ......then stop....and then rev the crap out of your engine until the second try and then go right to that number worse case......pay for a re run and before the re run drive around a bit to recharge the battery or get a trickeler. Link to comment Share on other sites More sharing options...
Don Pisto Posted January 24, 2007 Author Share Posted January 24, 2007 The system was built for a daily driver, I just want to see how loud I am. My enclosure is damn huge and I know DD subs get loud. At this comp I highly doubt there were will be that many serious competitors. I'm sure there will be some, but I'm goin for kicks, not to earn point and go to nationals or WF. I just want to do as best as I can. I'll be in Street B, and you mentioned revving the engine, but in street b, the vehicle must be off, so i can't do that at all. I have a few bass CD's, but none of them really have the frequencies I'm looking for, I'm hoping to pick some Bass Mekanik up before Saturday or hopefully they'll have a CD either to use or purchase at the comp. Would it be wise to burp say 38 Hz, then 40, then 45, then 50, then 55, or whatever it may be, basically several different frequencies in a single run? Link to comment Share on other sites More sharing options...
Unpredictableacts Posted January 24, 2007 Share Posted January 24, 2007 The system was built for a daily driver, I just want to see how loud I am. My enclosure is damn huge and I know DD subs get loud. At this comp I highly doubt there were will be that many serious competitors. I'm sure there will be some, but I'm goin for kicks, not to earn point and go to nationals or WF. I just want to do as best as I can. I'll be in Street B, and you mentioned revving the engine, but in street b, the vehicle must be off, so i can't do that at all. I have a few bass CD's, but none of them really have the frequencies I'm looking for, I'm hoping to pick some Bass Mekanik up before Saturday or hopefully they'll have a CD either to use or purchase at the comp. Would it be wise to burp say 38 Hz, then 40, then 45, then 50, then 55, or whatever it may be, basically several different frequencies in a single run? They will provide a cd for the competitiors.....I would start at about 35 and work my way up one at a time. Link to comment Share on other sites More sharing options...
Pballer2005 Posted February 8, 2007 Share Posted February 8, 2007 i know this is a slightly old thread but i got the latest bass mekanic cd (called reload) and it has a bass sweep on the second cd. starts out at 120hz and gets so low the speaker just kinda pokes in and out a few time a second, something like 20hz. Link to comment Share on other sites More sharing options...
Don Pisto Posted February 8, 2007 Author Share Posted February 8, 2007 About a week ago I bought DB Jamz vol. 2, i know vol. 7 is comin out but all I needed was test tones. This cd is perfect. has frequencies from 45-60 hz, both bursts and regular sine wavs and its got a few sweeps. Only 3 bucks shipped on amazon.com too, well worth it. Link to comment Share on other sites More sharing options...
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