cabin gain,, and octaves - diyAudio
Go Back   Home > Forums > General Interest > Car Audio

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 11th April 2005, 02:01 AM   #1
diyAudio Member
 
Join Date: Jan 2005
Location: New Brunswick
Default cabin gain,, and octaves

ok,, winisd predicts that 2 kicker comp vr 18 inchers will produce a max spl of 120 db at 30 hertz,,,

what would the cabin gain be,, considering your in a honda element. which is a relugar sized suv

i've been reading about cabin gain,,,, one question

whats an octave? and if its 12 db per octave gain below 40 hertz, when does it reach its first 12 db of gain,, 30 hertz??
__________________
My 100$ (final cost) line arrays will blow you away
  Reply With Quote
Old 11th April 2005, 07:20 PM   #2
diyAudio Member
 
Join Date: Nov 2004
Location: sk
Send a message via AIM to ocool_15 Send a message via Yahoo to ocool_15
Default octave

one octave is a doubling or a half of frequency ie
20 40center 80Hz. 2 octaves im not sure but i think it goes like this: 40center 80 160 320 640 1280Hz
  Reply With Quote
Old 11th April 2005, 07:40 PM   #3
Mark Kravchenko --- www.kravchenko-audio.com
diyAudio Member
 
mwmkravchenko's Avatar
 
Join Date: Jan 2002
Location: Perth Canada
Default ROugh Musical octaves

Here's how it works

16-32hz
32-64hz
64-128hz
128-256hz
256-512hz
512-1024hz
1024-2048hz
2048-4096hz
4096-8192hz
80192-16384hz

These are rough numbers

Different instruments and such tune slightly higher or lower and the octaves shown are therefore not exact. But the concept is pretty damn close.

A pipe organ and a synth are about the only things that plumb the lowest octave.

Kick drum is around 100 hz

The highest note on a violin is in the 4000 hz range.

Heres a freaky one. THe harmonics of cymbals are up and above 40,000 hz dog and bat zone.

Cabin gain works like this. Say it starts off at 60 hz. Down one octave or down to 30hz you will get a natural boost of 12db or a little more than twice as loud. The next lowest octave will get another 12 db on top of what you allready have. THis again is theoretical. In a car the interior dimensions are short. SOme lower frequencies will naturally collapse because of the produce air pressure wave being swamped out by its own reflection. These are calling standing waves.

MArk
__________________
Mark
  Reply With Quote
Old 12th April 2005, 02:32 AM   #4
Bose(o) is offline Bose(o)  Canada
diyAudio Member
 
Join Date: Dec 2001
Location: Ottawa, Ontario, Canada
To get an idea of the loudness your subs will create (theoretical MAX) while pushing drivers to maximum linear excursion you can use this equation:
=(197+20*LOG(Sd*(Xmax/10)/1000000))-20*LOG(Vroom)

Sd (cm^2), Xmax (mm), Vroom (m^3)

Lucky for you I've got a spreadsheet that spits out information quickly.

Should hit a max of about 138dB.
__________________
ERTW 4 life!
"the day has 24hours. If that is not enough take the night."-Roemhild
  Reply With Quote
Old 12th April 2005, 02:35 AM   #5
Bose(o) is offline Bose(o)  Canada
diyAudio Member
 
Join Date: Dec 2001
Location: Ottawa, Ontario, Canada
Oh yeah, Canada represent...eh!
__________________
ERTW 4 life!
"the day has 24hours. If that is not enough take the night."-Roemhild
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Converting between Hz and octaves? Javachip Multi-Way 4 6th April 2006 07:43 AM
Zero mH Drivers, Clarity and Time Differences Between Octaves kelticwizard Multi-Way 0 17th December 2005 02:15 PM
cabin gain in a ford explorer Chris8sirhC Car Audio 5 17th May 2005 05:12 PM
car cabin room sma Car Audio 2 4th February 2005 05:00 AM
Cabin Gain BassAwdyO Car Audio 0 7th January 2005 02:16 AM


New To Site? Need Help?

All times are GMT. The time now is 07:10 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2