# How to Calculate Resonante Frequency



## danielp (Jan 6, 2010)

Hi,

Any 1 knows what the formula is to calculate Resonant Frequency in a vehicle?


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## britdevine (Jan 21, 2010)

*Re: Ho to Calculate Resonante Frequency*

I would like to know as well


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## ChrisB (Jul 3, 2008)

*Re: Ho to Calculate Resonante Frequency*

finding car resonance frequency


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## Nitin (May 28, 2008)

*Re: Ho to Calculate Resonante Frequency*

Hi Daniel - as you know that we guys in South Africa are as high as any other part of the world with our SPL numbers and hold a few world records - so in June 2005 we had a visit from Moe Sabourin who was at that time the president of IASCA - he did a workshop/seminar type of lecture here during his visit and the attendees were given notes. Obviously the attendees got to discuss SPL (and after the seminar a bit of SQ as well) with Moe

now the original pages i have lost ages ago but before i lost those i managed to scan them - and this was early on in my experience with computers - so they were not saved in a perfect manner - but i have got a PDF version which is readable - its around 2mb big which isnt a huge file for 13 pages but which probably accounts for the poor quality of the file so apologies for that 

but here you go - its an interesting read as a summary of what we all discussed in that workshop - obviously a lot more went on there than these printed notes but before that and subsequently SA did have very strong competitors in the SPL arena so that seminar did help a bit 

one of the huge sections discussed was how to get the resonant frequency of the vehicle and why each of those methods described works well - one thing they dont mention is that after determining your resonant frequency you tune your subwoofer enclosure to peak at that resonant frequency - how well this is achieved is dependent on the software that you use (termlab is terrific and bassbox pro is also okay but winisd is a decent freebie and can give you workable usable framework to work on) and how far or close you get to your calculated figures also depends on having a specific temperature in the vehicle as mentioned in that thread above also ie the effects of the speed of the sound due to changes in temperature 

either way heres those workshop notes - hope that they are readable for whoever downloads them - i do have the original hardcopy somewhere at home - if i do find those i will rescan them in a better quality and re-upload but to be honest i have so much stuff all over the place i cant make a promise on that cos i have no idea if i will find it or not 

View attachment iasca SPL workshop.pdf


remember also that this is all from 2005 and technology and knowledge have advanced slightly but most of the basics do remain the same so most of what is said there remains valid to today - good luck in your box building efforts


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## RyanM923 (May 12, 2007)

^^^nice read.


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## danielp (Jan 6, 2010)

Nice Read indeed.
Thanks Nitin.


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