I'm preparing to build an enclosure for the Adire Tempest driver using
Adire's plans called the "Adire Alignment". This will be a 7.56 cu
ft box with two 3" diameter ports. The sub is downfiring.

I have all the plans and needed wood measurements, however, I have
concern about how to stuff the recommended 4 lbs of polyfill. By
filling the entire encolsure evenly with 4 lbs of polyfill, I'm
concerned that there is some risk that the polyfill will settle around
the back of the driver or into the port tubes.

Any suggestions about how to prevent this? Could I use some type of
screen material or perhaps an additional brace (with numberous holes)
placed above the subwoofer?

Thanks,

bsguidry

On 19 Dec 2003 08:56:18 -0800, (bsguidry) wrote:

I'm preparing to build an enclosure for the Adire Tempest driver using
Adire's plans called the "Adire Alignment". This will be a 7.56 cu
ft box with two 3" diameter ports. The sub is downfiring.

I have all the plans and needed wood measurements, however, I have
concern about how to stuff the recommended 4 lbs of polyfill. By
filling the entire encolsure evenly with 4 lbs of polyfill, I'm
concerned that there is some risk that the polyfill will settle around
the back of the driver or into the port tubes.

Any suggestions about how to prevent this? Could I use some type of
screen material or perhaps an additional brace (with numberous holes)
placed above the subwoofer?

Thanks,

bsguidry

Stretch cords across the inside of the cabinet and weave the polyfill
through them.

d

_____________________________

http://www.pearce.uk.com

In article , (bsguidry) wrote:
I'm preparing to build an enclosure for the Adire Tempest driver using
Adire's plans called the "Adire Alignment". This will be a 7.56 cu
ft box with two 3" diameter ports. The sub is downfiring.

I have all the plans and needed wood measurements, however, I have
concern about how to stuff the recommended 4 lbs of polyfill. By
filling the entire encolsure evenly with 4 lbs of polyfill, I'm
concerned that there is some risk that the polyfill will settle around
the back of the driver or into the port tubes.

Any suggestions about how to prevent this? Could I use some type of
screen material or perhaps an additional brace (with numberous holes)
placed above the subwoofer?

Allthough it will settle some, the stuff holds itself somewhat. You can keep it back
by simple stapling some strands to the sides. I often use black polypropylene
gutter guard, which comes in rolls. Cut it and it can be stapled or tacked to the sides,
holding back the stuffing. Its possible to also glue or tie it around the driver basket.
There are many other things and methods to do the trick. I would not generally
recommend even stuffing a cabnet with ports. I usually just use 2-3 inches of
foam tacked to the sides of the box. By all means, keep the stuffing
away from the ports and drivers unless you want its effects.

greg

bsguidry wrote:

I'm preparing to build an enclosure for the Adire Tempest driver using
Adire's plans called the "Adire Alignment". This will be a 7.56 cu
ft box with two 3" diameter ports. The sub is downfiring.

Redesign the box for vertical placement of the loudspeaker. You will
like having done this in 10 years. Just my opinion, ymmv.

I have all the plans and needed wood measurements, however, I have
concern about how to stuff the recommended 4 lbs of polyfill. By
filling the entire encolsure evenly with 4 lbs of polyfill, I'm
concerned that there is some risk that the polyfill will settle around
the back of the driver or into the port tubes.

Any suggestions about how to prevent this? Could I use some type of
screen material or perhaps an additional brace (with numberous holes)
placed above the subwoofer?

Gregs suggestion on how to keep the polyfill in place will still apply.

bsguidry


Kind regards

Peter Larsen

--
************************************************** ***********
* My site is at: http://www.muyiovatki.dk *
************************************************** ***********

Peter Larsen wrote in message ...
bsguidry wrote:

I'm preparing to build an enclosure for the Adire Tempest driver using
Adire's plans called the "Adire Alignment". This will be a 7.56 cu
ft box with two 3" diameter ports. The sub is downfiring.

Redesign the box for vertical placement of the loudspeaker. You will
like having done this in 10 years. Just my opinion, ymmv.

I have all the plans and needed wood measurements, however, I have
concern about how to stuff the recommended 4 lbs of polyfill. By
filling the entire encolsure evenly with 4 lbs of polyfill, I'm
concerned that there is some risk that the polyfill will settle around
the back of the driver or into the port tubes.

Any suggestions about how to prevent this? Could I use some type of
screen material or perhaps an additional brace (with numberous holes)
placed above the subwoofer?

Gregs suggestion on how to keep the polyfill in place will still apply.

bsguidry


Kind regards

Peter Larsen

Thanks to all who have responded. I believe I will use a combination
of sticking the polyfill to the sides and perhaps using cords or twine
as a net above the driver and ports.

As far as mounting the driver for a vertical alignment, I'd like to
know more why I'd appreciate this design in 10 years. Unfortunately,
I have two toddlers who haven't learned to keep out of my
electronics. Having the sub mounted underneath would offer a bit more
protection than if it were side mounted.

bsguidry

bsguidry wrote:

As far as mounting the driver for a vertical alignment,
I'd like to know more why I'd appreciate this design in
10 years.

Gravity will eventually cause the loudspeaker unit to leave its correct
rest position. This is not something that happens fast, but eventually
it will happen.

Unfortunately, I have two toddlers who haven't learned
to keep out of my electronics.

Aha ...

Having the sub mounted underneath would offer a bit more
protection than if it were side mounted.

Indeed. Design sure never is simple .... and even if a metal screen is
used, then the spilled beverage and icecream risk remains. I would try
to find a solution with a hidden loudspeaker unit, but then it becomes a
total redesign. One way of getting the loudspeaker unit hidden is to go
for a bandpass reflex box with a front chamber instead. But you already
appear to have a lock on the target ... or do you?

http://www.tachyon.co.jp may be an interesting passtime if you want to
look for possible solutions that may be somewhat beyond your initial
aim. The also have a subsite for WE555 Replacement Diaphragm ... just as
an a pro pos to a thread in this forum some weeks ago.

bsguidry


Kind regards

Peter Larsen

--
************************************************** ***********
* \\\\\\\ Quality Ascii handcrafted by Peter Larsen /////// *
* \\\\\\\ My site is at: http://www.muyiovatki.dk /////// *
************************************************** ***********

On 22 Dec 2003 11:34:29 -0800, (bsguidry) wrote:

As far as mounting the driver for a vertical alignment, I'd like to
know more why I'd appreciate this design in 10 years. Unfortunately,
I have two toddlers who haven't learned to keep out of my
electronics. Having the sub mounted underneath would offer a bit more
protection than if it were side mounted.

The Tempest, as with most sub drivers, is designed to be used
vertically. If you mount it horizontally, it will over time sag on its
suspension, introducing non-linearity. Even with vertical mounting,
it's advisable to rotate the driver by 180 degrees every few years, to
avoid the cone eventually rubbing in the gap.

As it happens, I'm about to build a 'killer' sub using a pair of
Tempests and a 500 watt amp in a 200 litre sealed cabinet. The drivers
will be vertically mounted, for the reason given. It should be X-Max
limited to less than 20Hz, and provide in-room levels of 120dB from
20Hz up with corner mounting, with a low-Q alignment using Linkwitz
Transform equalisation.

Hopefully, this will be 'adequate', for somewhat less than the cost of
a REL Q201. :-)
--

Stewart Pinkerton | Music is Art - Audio is Engineering

This is off topic but you might want to consider an infinite
baffle arrangement. It's inexpensive and easy to construct
arrangement that yields incredibly clean, low distortion, very
deep bass at unbelievable SPL. Certainly the cleanest and
loudest bass I've ever heard.

With multiple (hidden) drivers you can literally achieve house
damaging levels with a flat response from below 10Hz to well
above 100Hz...at a fraction of the cost of a comparable box sub.
All this without a monster amplifier and no big ugly box in the
corner (and no polyfill concerns). I usually recommend four high
excursion 15" drivers (Stryke AV15 is the current
performance/dollar leader but the older Adire Tempest and Dayton
15" drivers compete well). For $1k total (drivers, amp,
construction materials) you can blow windows out of their frames
without the drivers breaking a sweat (i.e. still within linear
Xmax).

IB maximizes Hoffman's Iron Law. Hoffman's Iron Law states that
the efficiency of a woofer system is directly proportional to its
cabinet volume and the cube of its cutoff frequency (the lowest
frequency it can usefully reproduce). With any box sub there is a
tradeoff between efficiency, volume, and low frequency response.
With IB the volume is 'infinite' which maximizes the efficiency
and cutoff to simply the properties of the bare driver. It
doesn't get any better. Power compression/distortion isn't an
issue like a box sub and you only need a relatively tiny amp.

FAQ:
https://home.comcast.net/~ttriff/

Gallery pictures pages 1 and 2 with construction links
https://home.comcast.net/~ttriff//page2IB-Gallery.html
https://home.comcast.net/~ttriff//page3IB-Gallery2.html

Forum
http://f20.parsimony.net/forum36475/

IB: no box, no box-like sound

"Rusty Boudreaux" wrote in message ...
This is off topic but you might want to consider an infinite
baffle arrangement. It's inexpensive and easy to construct
arrangement that yields incredibly clean, low distortion, very
deep bass at unbelievable SPL. Certainly the cleanest and
loudest bass I've ever heard.

With multiple (hidden) drivers you can literally achieve house
damaging levels with a flat response from below 10Hz to well
above 100Hz...at a fraction of the cost of a comparable box sub.
All this without a monster amplifier and no big ugly box in the
corner (and no polyfill concerns). I usually recommend four high
excursion 15" drivers (Stryke AV15 is the current
performance/dollar leader but the older Adire Tempest and Dayton
15" drivers compete well). For $1k total (drivers, amp,
construction materials) you can blow windows out of their frames
without the drivers breaking a sweat (i.e. still within linear
Xmax).

IB maximizes Hoffman's Iron Law. Hoffman's Iron Law states that
the efficiency of a woofer system is directly proportional to its
cabinet volume and the cube of its cutoff frequency (the lowest
frequency it can usefully reproduce). With any box sub there is a
tradeoff between efficiency, volume, and low frequency response.
With IB the volume is 'infinite' which maximizes the efficiency
and cutoff to simply the properties of the bare driver. It
doesn't get any better. Power compression/distortion isn't an
issue like a box sub and you only need a relatively tiny amp.

FAQ:
https://home.comcast.net/~ttriff/

Gallery pictures pages 1 and 2 with construction links
https://home.comcast.net/~ttriff//page2IB-Gallery.html
https://home.comcast.net/~ttriff//page3IB-Gallery2.html

Forum
http://f20.parsimony.net/forum36475/

IB: no box, no box-like sound

I wish I had investigated Infinite Baffles further prior to beginning.
I hadn't envisioned doing an infinite baffle in what appears to be
the standard approach on the websites above. It definitely would lead
to simpler carpentry and no huge boxes in the room. I may move to
this in the near future.

I've already begun work on the 214L box for the Tempest. The wood is
all cut and much of it assembled. I'll go from there.

One question about port tubes. When using flared port kits,
measurements are given for the center tube length. In the case of the
Tempest plans it indicates a center tube length of 11". I'm assuming
this is the actual length of the center tube piece before the flared
ends are attached. The flared ends slip over the center tube so
measuring it afterwards would be about 10.5".

bsguidry

On Tue, 23 Dec 2003 04:39:04 -0600, "Rusty Boudreaux"
wrote:

With any box sub there is a
tradeoff between efficiency, volume, and low frequency response.
With IB the volume is 'infinite' which maximizes the efficiency
and cutoff to simply the properties of the bare driver. It
doesn't get any better. Power compression/distortion isn't an
issue like a box sub and you only need a relatively tiny amp.

FAQ:
https://home.comcast.net/~ttriff/

Gallery pictures pages 1 and 2 with construction links
https://home.comcast.net/~ttriff//page2IB-Gallery.html
https://home.comcast.net/~ttriff//page3IB-Gallery2.html

Forum
http://f20.parsimony.net/forum36475/

IB: no box, no box-like sound

OTOH, your ceiling will rattle like crazy..........

BTW, if using an open baffle, watch out that you don't rip the
suspension loose at low frequencies, when you can easily drive *way*
beyond Xmax! Note that most of the ultra-long throw drivers are
intended for use in a relatively small sealed boxes, with heavy EQ and
big amps. Go to the Linkwitz Lab website, and run the numbers through
for large box volumes - you get Xmax limiting at low frequencies with
very low power.

BTW, I'm in a similar situation to you, I have a large loft space
above my listening room, but I'm going with a pair of Tempests in a
200 litre sealed box, driven by a 500 watt amp. This works pretty
well, Xmax limited from 30 Hz down so achieving maximum possible SPL,
but without much spare power to overload the driver. Should give a
clean 120 dB in-room from 20 Hz up.
--

Stewart Pinkerton | Music is Art - Audio is Engineering