true?

Hey guys, i was on my honda civic website, and i saw a new forum called car audio. I was reading a few things on there, and ran across this statement.

"For example...let's use the JL Audio W7 series for arguements sake. The 10W7 has an efficiency of 84.3 SPL @ 1W/1M and the 8W7 has a efficiency of 82.7 SPL @ 1W/1M. The 10W7 has a power rating of 500watts continuous which is the recommended power rating for the woofer by JL. The 8W7 has a continuous power handling of 300watts but they recommend their 250/1 to power it. OK, if you take that single 10" and put 1watt of power in it, it will play 84.3db but everytime you double the power that rating will go up 3db so basically with 500watts of power it will play 108.3db. Now do the same with the 8W7, but before you start you add 3db because you will be running 2 8's, so instead of starting with a 82.7 SPL you will be starting with 85.7. Now that number with 500watts of power it will play 112.7db. Doesn't seem like alot but believe me that's a big deal and is very noticeable."

I was just wondering how true that was/is. it makes sense, but i dont think its that easy.

What's the website?

Here is a basic scale based on these numbers

84.3 = 1

87.3 = 2

90.3 = 4

93.3 = 8

96.3 = 16

99.3 = 32

102.3 = the square root of an the capacity of your dogs stomach

105.3 = 128

108.3 = 256

111.3 = 512

So either my math is out or their math is out. Maybe they did not factor in the dogs stomach? The principle that they list is correct but it seems the numbers are a little off.

Plus due to losses and inefficiencies, it is not always a stricly accurate algorithm. 

And you have to use a schnauzer to get the most accurate dog stomach offset numbers.  If you use the standard golden retriever factor the math comes out closer to the results in the original message.  I think Bose and Sony use a wiener dog as their baseline, which is how they can advertise fake power ratings.

lmao. u guys are awesome. to rob, the website is www.clubhonda.com 

this is a link to the thread. its about the 4th or 5th post down.

http://www.clubhonda.com/forums/showthread.php?s=&threadid=13442

check it out.

And that's just the subs side of things.  This isn't taking into account the environment the sub is used in (room transfer functions) or the impact the enclosure will have on efficiency.  For subs, efficiency ratings are thrown out the window as soon as you place the sub in an enclosure.  Also, what frequency are we talking about?  If I can find the impedance peak I can get the sub to be REALLY loud off of one watt.

From what I understand, one company rates their subs at half a meter and in vehicle.  So their numbers are extremely inflated.

Steven Kephart

Adire Audio

Not at all.  A bunch of chrome and flame designs actually adds efficiency to the driver.  Honest.

Steven Kephart

Adire Audio