Too much polyfill??

[Robert Easton]

I recently built a sealed box for three jl audio 12w6v2's with each in its
own cabinet. I put polyfill in the box and it seems to not hit the lows like
I like. I was wondering if the polyfill might be a problem. or it needs some
time to break in or I need more space. Anyone have any comments. I just dont
want to be too hasty pulling out the fill. I was always told that about a
pound of fill to a cubic foot.

[Scott Gardner]

One pound per cubic foot is in the right ballpark. How big is the
enclosure volume for each sub? Polyfill will mimic the effects of a
larger box, but it will only get you so much.

Scott Gardner

On Sat, 24 Apr 2004 23:04:46 -0500, "Robert Easton"
> wrote:

>I recently built a sealed box for three jl audio 12w6v2's with each in its
>own cabinet. I put polyfill in the box and it seems to not hit the lows like
>I like. I was wondering if the polyfill might be a problem. or it needs some
>time to break in or I need more space. Anyone have any comments. I just dont
>want to be too hasty pulling out the fill. I was always told that about a
>pound of fill to a cubic foot.
>

[Robert Easton]

The chamber for each sub is around 1.1 gross cubic feet.
"Scott Gardner" > wrote in message
...
> One pound per cubic foot is in the right ballpark. How big is the
> enclosure volume for each sub? Polyfill will mimic the effects of a
> larger box, but it will only get you so much.
>
> Scott Gardner
>
> On Sat, 24 Apr 2004 23:04:46 -0500, "Robert Easton"
> > wrote:
>
> >I recently built a sealed box for three jl audio 12w6v2's with each in
its
> >own cabinet. I put polyfill in the box and it seems to not hit the lows
like
> >I like. I was wondering if the polyfill might be a problem. or it needs
some
> >time to break in or I need more space. Anyone have any comments. I just
dont
> >want to be too hasty pulling out the fill. I was always told that about a
> >pound of fill to a cubic foot.
> >
>

[Scott Gardner]

Well, you're on the small side there, so that might be part of the
problem. Considering the driver displacement, you've only got about 1
cubic foot per driver, and the recommended size is 1.25 cubic feet per
speakers.

What's the overall impedance of your subwoofer setup, and how much
power are you providing to them?

Scott Gardner



On Sun, 25 Apr 2004 08:00:32 -0500, "Robert Easton"
> wrote:

>The chamber for each sub is around 1.1 gross cubic feet.


>"Scott Gardner" > wrote in message
...
>> One pound per cubic foot is in the right ballpark. How big is the
>> enclosure volume for each sub? Polyfill will mimic the effects of a
>> larger box, but it will only get you so much.
>>
>> Scott Gardner
>>
>> On Sat, 24 Apr 2004 23:04:46 -0500, "Robert Easton"
>> > wrote:
>>
>> >I recently built a sealed box for three jl audio 12w6v2's with each in
>its
>> >own cabinet. I put polyfill in the box and it seems to not hit the lows
>like
>> >I like. I was wondering if the polyfill might be a problem. or it needs
>some
>> >time to break in or I need more space. Anyone have any comments. I just
>dont
>> >want to be too hasty pulling out the fill. I was always told that about a
>> >pound of fill to a cubic foot.
>> >
>>
>

[Robert Easton]

I put them in a 1 cubic foot to try and get agood tight beat but it seams to
be losing the low end which I didnt think should happen. The space req. is
between .90 and 1.5 cubic feet. I have the three running at about 2.67 ohms
with about 1100 good watts going to it (Rockford fosgate 1050S, 4 ohm stable
bridged but does 2 ohms just fine.)
"Scott Gardner" > wrote in message
...
> Well, you're on the small side there, so that might be part of the
> problem. Considering the driver displacement, you've only got about 1
> cubic foot per driver, and the recommended size is 1.25 cubic feet per
> speakers.
>
> What's the overall impedance of your subwoofer setup, and how much
> power are you providing to them?
>
> Scott Gardner
>
>
>
> On Sun, 25 Apr 2004 08:00:32 -0500, "Robert Easton"
> > wrote:
>
> >The chamber for each sub is around 1.1 gross cubic feet.
>
>
> >"Scott Gardner" > wrote in message
> ...
> >> One pound per cubic foot is in the right ballpark. How big is the
> >> enclosure volume for each sub? Polyfill will mimic the effects of a
> >> larger box, but it will only get you so much.
> >>
> >> Scott Gardner
> >>
> >> On Sat, 24 Apr 2004 23:04:46 -0500, "Robert Easton"
> >> > wrote:
> >>
> >> >I recently built a sealed box for three jl audio 12w6v2's with each in
> >its
> >> >own cabinet. I put polyfill in the box and it seems to not hit the
lows
> >like
> >> >I like. I was wondering if the polyfill might be a problem. or it
needs
> >some
> >> >time to break in or I need more space. Anyone have any comments. I
just
> >dont
> >> >want to be too hasty pulling out the fill. I was always told that
about a
> >> >pound of fill to a cubic foot.
> >> >
> >>
> >
>

[Scott Gardner]

Yep, you're right that the allowable range goes all the way down to .9
cubic feet net per driver, I was just going off of the recommended
enclosure size from the data sheet that suggests 1.25 cubic feet.
You will lose some of the low-frequency extension as your box gets too
small, but it's hard to say exactly how much. Have you tried modeling
your speakers in one of the software programs and seeing what kind of
a diffference the extra 25% volume would make?

Scott Gardner

On Sun, 25 Apr 2004 16:41:06 -0500, "Robert Easton"
> wrote:

>I put them in a 1 cubic foot to try and get agood tight beat but it seams to
>be losing the low end which I didnt think should happen. The space req. is
>between .90 and 1.5 cubic feet. I have the three running at about 2.67 ohms
>with about 1100 good watts going to it (Rockford fosgate 1050S, 4 ohm stable
>bridged but does 2 ohms just fine.)
>"Scott Gardner" > wrote in message
...
>> Well, you're on the small side there, so that might be part of the
>> problem. Considering the driver displacement, you've only got about 1
>> cubic foot per driver, and the recommended size is 1.25 cubic feet per
>> speakers.
>>
>> What's the overall impedance of your subwoofer setup, and how much
>> power are you providing to them?
>>
>> Scott Gardner
>>
>>
>>
>> On Sun, 25 Apr 2004 08:00:32 -0500, "Robert Easton"
>> > wrote:
>>
>> >The chamber for each sub is around 1.1 gross cubic feet.
>>
>>
>> >"Scott Gardner" > wrote in message
>> ...
>> >> One pound per cubic foot is in the right ballpark. How big is the
>> >> enclosure volume for each sub? Polyfill will mimic the effects of a
>> >> larger box, but it will only get you so much.
>> >>
>> >> Scott Gardner
>> >>
>> >> On Sat, 24 Apr 2004 23:04:46 -0500, "Robert Easton"
>> >> > wrote:
>> >>
>> >> >I recently built a sealed box for three jl audio 12w6v2's with each in
>> >its
>> >> >own cabinet. I put polyfill in the box and it seems to not hit the
>lows
>> >like
>> >> >I like. I was wondering if the polyfill might be a problem. or it
>needs
>> >some
>> >> >time to break in or I need more space. Anyone have any comments. I
>just
>> >dont
>> >> >want to be too hasty pulling out the fill. I was always told that
>about a
>> >> >pound of fill to a cubic foot.
>> >> >
>> >>
>> >
>>
>

[Robert Easton]

I plugged in the new numbers and there was not a significant change. There
was a little in the lower end though. I guess I will just take out the fill
and see what the change is.
"Scott Gardner" > wrote in message
...
> Yep, you're right that the allowable range goes all the way down to .9
> cubic feet net per driver, I was just going off of the recommended
> enclosure size from the data sheet that suggests 1.25 cubic feet.
> You will lose some of the low-frequency extension as your box gets too
> small, but it's hard to say exactly how much. Have you tried modeling
> your speakers in one of the software programs and seeing what kind of
> a diffference the extra 25% volume would make?
>
> Scott Gardner
>
> On Sun, 25 Apr 2004 16:41:06 -0500, "Robert Easton"
> > wrote:
>
> >I put them in a 1 cubic foot to try and get agood tight beat but it seams
to
> >be losing the low end which I didnt think should happen. The space req.
is
> >between .90 and 1.5 cubic feet. I have the three running at about 2.67
ohms
> >with about 1100 good watts going to it (Rockford fosgate 1050S, 4 ohm
stable
> >bridged but does 2 ohms just fine.)
> >"Scott Gardner" > wrote in message
> ...
> >> Well, you're on the small side there, so that might be part of the
> >> problem. Considering the driver displacement, you've only got about 1
> >> cubic foot per driver, and the recommended size is 1.25 cubic feet per
> >> speakers.
> >>
> >> What's the overall impedance of your subwoofer setup, and how much
> >> power are you providing to them?
> >>
> >> Scott Gardner
> >>
> >>
> >>
> >> On Sun, 25 Apr 2004 08:00:32 -0500, "Robert Easton"
> >> > wrote:
> >>
> >> >The chamber for each sub is around 1.1 gross cubic feet.
> >>
> >>
> >> >"Scott Gardner" > wrote in message
> >> ...
> >> >> One pound per cubic foot is in the right ballpark. How big is the
> >> >> enclosure volume for each sub? Polyfill will mimic the effects of a
> >> >> larger box, but it will only get you so much.
> >> >>
> >> >> Scott Gardner
> >> >>
> >> >> On Sat, 24 Apr 2004 23:04:46 -0500, "Robert Easton"
> >> >> > wrote:
> >> >>
> >> >> >I recently built a sealed box for three jl audio 12w6v2's with each
in
> >> >its
> >> >> >own cabinet. I put polyfill in the box and it seems to not hit the
> >lows
> >> >like
> >> >> >I like. I was wondering if the polyfill might be a problem. or it
> >needs
> >> >some
> >> >> >time to break in or I need more space. Anyone have any comments. I
> >just
> >> >dont
> >> >> >want to be too hasty pulling out the fill. I was always told that
> >about a
> >> >> >pound of fill to a cubic foot.
> >> >> >
> >> >>
> >> >
> >>
> >
>

[Daniel Snooks]

Robert Easton wrote
> I plugged in the new numbers and there was not a significant change. There
> was a little in the lower end though. I guess I will just take out the
fill
> and see what the change is.

Taking out the fill is not the solution. The fill is helping to give the
subs the illusion of more space. Is it possible for you to invert the subs?
That will gain you the displacement and should help you decide if another
0.1 - 0.15 cuft helps the low end you are looking for. Also, what frequency
are you crossing the subs at?

[FHLH002]

good suggestion....
Another question for Robert?
where and how are the subs installed? what kinda car/truck?

FHLH


"Daniel Snooks" > wrote in message
.. .
> Robert Easton wrote
> > I plugged in the new numbers and there was not a significant change.
There
> > was a little in the lower end though. I guess I will just take out the
> fill
> > and see what the change is.
>
> Taking out the fill is not the solution. The fill is helping to give the
> subs the illusion of more space. Is it possible for you to invert the
subs?
> That will gain you the displacement and should help you decide if another
> 0.1 - 0.15 cuft helps the low end you are looking for. Also, what
frequency
> are you crossing the subs at?
>
>

[Robert Easton]

They ate in a sealed box each in its own chamber. A little less than 1 cubic
foot for each. The vehicle is a 2001 nissan pathfinder. Powered with a
rockford fosgate 1050s at 2.67 ohms
"FHLH002" > wrote in message
...
> good suggestion....
> Another question for Robert?
> where and how are the subs installed? what kinda car/truck?
>
> FHLH
>
>
> "Daniel Snooks" > wrote in message
> .. .
> > Robert Easton wrote
> > > I plugged in the new numbers and there was not a significant change.
> There
> > > was a little in the lower end though. I guess I will just take out the
> > fill
> > > and see what the change is.
> >
> > Taking out the fill is not the solution. The fill is helping to give the
> > subs the illusion of more space. Is it possible for you to invert the
> subs?
> > That will gain you the displacement and should help you decide if
another
> > 0.1 - 0.15 cuft helps the low end you are looking for. Also, what
> frequency
> > are you crossing the subs at?
> >
> >
>
>