actually, some of Alpine's new line including the 9855 have "OEM Steering Remote Ready" which has a PAC module that is compatable with the S. I've never done it, but i know a few members on this board have installed thier new Alpines and retained the dash controls without a DCI.

however, Modifry's DCI adds extra features such as speed controlled volume, a must for any convertable.


As far as wattage to volume, here's a little writeup on the subject: loudness vs. wattage

what's interesting here is the db measurement, and this article points out that 3db does not qualify as being twice as loud, only "noticeably" louder.

by all means, show me your research. the volume to wattage relationship is something that many take for granted. i'm curious to seperate fact from fiction.

 

Yeah I goofed, I was thinking of something else. 10 db is twice as loud but up to a given point. As far as the SPL business, let me visit Termpro and Elite, and pull up the old articles. I'm not claiming anything, don't get it twisted.

 

for SPL terms, i always thought double the power and adding another sub gives you a 3db difference.

non im confused. so which is it?

 

i would have to agree with you.

the pros of a pilliar tweets is good stage height and great imaging.

tonally, it is pretty bad on my standards. your 16k-20hkz response will drop to pretty much nothing from the cancellation of the reflections and a great amount of simbilance.

 

+10 dB is always 2 times as loud. that's how it's mathematically defined, there's no 'given point.'

and 10x's the power is required to get +10 dB (2 times as loud)


double power = 3 dB. i'm not sure about the 'adding another sub' rule of thumb.


http://www.bcae1.com/decibel.htm

 

PJK3 agrees! thanks for getting my back brotha!

here's some more info and here's one that's perfect for fifth graders (yeah right)

 

Double the cone area is theoretically a 3db increase is from what I remembered.

Thanks for the links, that clears things up.

 

np, glad to help clear things up. log based stuff (ie decibels) is usually not very clear unless you're pretty familiar w/ the math behind it.


most of these rules of thumb make a ton of assumptions (ie double the power, but the same speakers, source material, ignoring inefficiencies, etc.)

assuming nothing else changes, and that you add another speaker w/ equivalent power -- i could see how 2x's the cone area might equal a 3 dB increase.
i'm still not sure, but it doesn't seem far fetched by any means.


Willie -- bro, i've got your back. anytime....

 

Double your power =+3db
Triple your cone area =+3db (if each additional speaker gets the same powers as the original.
To gain 1dB there would need to be a 26% increase in acoustical power or the pressure generated on the human ear.
Do not confuse acoustic power with electrical power they are different animals.

Examples would be
Electrical power examples
100dB at 100watts
103dB at 200 watts with same number of subs as before
106dB at 400 watts with same number of subs as before

Effective piston area examples
1 sub with 100watts =100dB
3 subs each with 100wats=103dB
6 subs each with 100 watts=106dB

To the human ear +10db is double the perceived loudness of the original dB level.
On an average a 3db differenced is the minimum change that the human ear can perceive.

Another example if you have a db meter and it is reading 0dB (meter is calibrated to read 0db based on ambient noise in the area). You turn up the volume to make the db meter read +10db that is double the perceived loudness or 260%increase in acoustical pressure.
Now if we go from +10 db up to +20db again that is double the perceived loudness and another 260% increase in acoustical pressure from the +10db reading
However it is now 100times more pressure than the original acoustic pressure at 0dB.

I hope that this helped.

 

that's the best answer yet. nicely done.

can we include this in the FAQs?