[Shotimes] subwoofer replacement

[sho2go]

Yes, the driver has to be subtracted out from the box volume.  The truly
anal among us wrap the driver in plastic and dip it into a bucket of water
(full) and then measure the volume of water displaced.  But its easy enough
to estimate with a ruler and a little arithmetic.  I design speakers in my
spare time (for home use), and the truth is unless you're after every last
dB for competitions, a little slop just isn't audible.  I am not an expert
on auto installations, but I understand that most pros make the box a little
smaller than would ordinarily be optimum in order to complement cabin gain,
which is substantial.  I have lots of box-optimizing software, and can help,
but it requires either the specs for the driver, or measurement equipment.
Mike

----- Original Message ----- 
From: "Kevin & Cheryl Airth" <clubairth@peoplepc.com>
To: "Bill Murray" <fordsho@cloud9grafx.com>; "SHOTimes"
<shotimes@autox.team.net>
Sent: Thursday, June 05, 2003 8:29 AM
Subject: Re: [Shotimes] subwoofer replacement


> Bill:
>  I could not get a 8" with the correct dimension for the box. They were
all
> too deep. I wanted to avoid modifying the stock box if possible at that
> time. In fact the JL unit is pretty tight for depth as it is. I must have
my
> dimension wrong on the JBL box? I will double check!
> .
> .
> I think I misspoke-I calculate the JBL box around .25 ft3? This brings up
a
> question I never got a good answer on. When calculating box volume does
the
> volume of the driver need to be subtracted from the total? How do you get
> the driver volume? Estimate from the dimensions?
> .