so I've been working and going to school for the past (many) months so i thought I'd get on and post what i did over the last two days to pass time. this time between semesters is killing me!
first box was for a friend, nothing special and was done to alpine specs for his Type R (My 1/2 blown infinity is in the pic)
My initial plan-
http://i40.photobucket.com/albums/e216/saxwonder05/audio/DavidsBox.jpg
When i was done-
http://i40.photobucket.com/albums/e216/saxwonder05/audio/Davidbox2.jpg
That project was two days ago. Yesterday i read this web page which pretty much took all my present knowledge and made sense of it all
( http://www.diysubwoofers.org/prt/dual_chamber.htm )
then came up with this concept to fit my friends Tracer
http://i40.photobucket.com/albums/e216/saxwonder05/audio/ABC3.jpg
as soon as i drew it up on Sketchup i started building with the extra wood from the first build
http://i40.photobucket.com/albums/e216/saxwonder05/2-1.jpg
http://i40.photobucket.com/albums/e216/saxwonder05/audio/_.jpg
Those were build pix RIGHT after, here is one in car-
http://i40.photobucket.com/albums/e216/saxwonder05/audio/ABC7.jpg
(as you can tell i moved the ports last minute, i liked the look of them in the center)
i LOVE the sound from the Dual Chamber Tri Tune Setup- i placed tthe ports along the center wall, slightly dropping the tuning frequency, in the end it came out something like this...
Bigger Chamber-1.6cuft-tuned to 28hz
Smaller Chamber-.8cuft-tuned to 41hz
its way to early in the life of this box to tell anything specific, soon i'll run it through genre tests and see how it handles.
enjoy
-Drew
Replies (9)
newB on 01/18/2008 21:59:36
i just realized the sketchup drawing doesn't have specs-
http://i40.photobucket.com/albums/e216/saxwonder05/audio/ABC4.jpg
there is a slight typo- it shows 1.7cuft when really its 1.6
-Drew
Ash on 01/19/2008 04:29:04
You better watch that creativity! I hear Bose is a nasty mutha to deal with...... LOL!
How about a good description of the tonal quality, advantages, and drawbacks so far....
newB on 01/19/2008 04:43:34
Tonal Quality in general is deep, "fat" the kind of sound that makes you feel like your swimming. just by listening to music, as far as response curve (by ear) it seems similar to a 6th order bandpass curve, VERY strong and present from 50 or so down with a steep roll off around 25hz (by ear) i was getting a small amount of port noise when the box was in my car, directly behind the drivers seat, possibly due to the arrangement of the ports or maybe because I'm using 3inch ports, but when the box was placed in the customers trunk it was impossible to hear.(port noise that is)
quite frankly it sounds like it has two tuning frequencies. we were getting trunk, roof, and steering wheel rattle from a single 10 in this box (just below 30hz) i might try and pull off some some Pete style response vids of people realizing its only a single ten (i had a hilarious one on the first day)
MORE tests, and a video or two tomorrow!!
-Drew
swez on 01/19/2008 10:56:10
Interesting plan here Drew. This is similar to a 6th order BP with the benefit of more direct cone radiation in the upper bass region. (60-100 Hz.)
Another neat feature is the dual chambers and porting nodes in each segment of the box. The larger ported section reinforces the deep, low bass and the smaller chamber gives a bit more bump at 40-60 Hz. Here, I would expect two bumps in a frequency sweep tone and SPL measurments where the ports are tuned in each chamber. (Not very musical, but lots of deep bump and some punch too)
Lastly, be mindful of the power fed to any woofer used in this design. There is little cone back pressure, (which meas) minimal excursion of the cone. That could easily fry a coil when using low power handling subs that are not able to cool themselves well under these conditions. It would be wise to use a very robust sub with above average heat dissapation characteristics.
Swez
newB on 01/19/2008 20:41:54
Right now its an Ascendant Audio Assassin 10inch woofer, which is a strong woofer but actually doesn't cool itself as well as i had hoped when buying it.
we're having no problems with excursion here- the single 10 doing 28hz is at full excursion, and stays moving a good deal throughout the range. i'm actually looking for a woofer with stiffer suspension right now, and better voice coil vents.
vids coming soon!!
-Drew
newB on 01/20/2008 02:34:07
OH NO!!!!!!!!!!!!!!!!!!!!
>_<
http://i40.photobucket.com/albums/e216/saxwonder05/DCTT3.jpg
http://i40.photobucket.com/albums/e216/saxwonder05/DCTT5.jpg
looks like now i gotta build THIS!!!
-Drew
swez on 01/20/2008 14:41:36
Interesting idea here too! (A dual tuned venting system)
One thing I don't get here, is the longer vent alignment. It's odd to see that overhanging panel lip at the right rear corner of the drawing??? It would seem like an obstruction or perhaps a wave guide that would cancel out unwanted bass nodes? Other than that, the longer vent will act like an acoustical wave guide or labyrinth type vent.
Like the rounded corners on each vent panel joint as this allows a smooth transition of bass as it passes through the venting system. This seems to be a nice variation of a 3 in 1, subwoofer enclosure.
1. Front cone bass radiation
2. Short port for lower midbass punch (What frequency is hard to say?)
3. Long port for deep bass tuning (Tuned well below 40 Hz. looks likely)
Neat and a very good challenge to any skilled enclosure builder. Lots of router work here too. (Use a carbide type half round bit on this one so you don't burn the wood or mangle a cheap bit.
Swez
newB on 01/20/2008 15:25:44
oh yeah i have a nice router with a good round bit that just destroys MDF corners.
this is how ive been designing these- how i was just taught its simple and easy to setup and sounds amazing so far.
"first start by selecting a standard ported alignment for the driver in question. Then, select two ports of equivalent length and diameter to tune the system to the required frequency. Split the required volume for the alignment into two, placing one port in the smaller chamber (1/3 total volume), and the other port and driver in the larger chamber (2/3 total volume). Finally, join the two chambers together with a port that's the same size and length as the ports used to vent the chambers to the outside."
All three ports, (1:out large chamber 2:connecting chambers 3:out small chamber) are ALL the same lengthxwidth what changes the tuning frequency is the size of the chamber they are comming from.
-Drew
newB on 01/20/2008 15:28:19
oh and on the second Slot Vent Style, if i remember correctly the high port is ~44hz and the low tuned is ~30hz its the same box that i have already built but in a slot vent with ~15sqin of port instead of the aero port style 7sqin.
-Drew
first box was for a friend, nothing special and was done to alpine specs for his Type R (My 1/2 blown infinity is in the pic)
My initial plan-
http://i40.photobucket.com/albums/e216/saxwonder05/audio/DavidsBox.jpg
When i was done-
http://i40.photobucket.com/albums/e216/saxwonder05/audio/Davidbox2.jpg
That project was two days ago. Yesterday i read this web page which pretty much took all my present knowledge and made sense of it all
( http://www.diysubwoofers.org/prt/dual_chamber.htm )
then came up with this concept to fit my friends Tracer
http://i40.photobucket.com/albums/e216/saxwonder05/audio/ABC3.jpg
as soon as i drew it up on Sketchup i started building with the extra wood from the first build
http://i40.photobucket.com/albums/e216/saxwonder05/2-1.jpg
http://i40.photobucket.com/albums/e216/saxwonder05/audio/_.jpg
Those were build pix RIGHT after, here is one in car-
http://i40.photobucket.com/albums/e216/saxwonder05/audio/ABC7.jpg
(as you can tell i moved the ports last minute, i liked the look of them in the center)
i LOVE the sound from the Dual Chamber Tri Tune Setup- i placed tthe ports along the center wall, slightly dropping the tuning frequency, in the end it came out something like this...
Bigger Chamber-1.6cuft-tuned to 28hz
Smaller Chamber-.8cuft-tuned to 41hz
its way to early in the life of this box to tell anything specific, soon i'll run it through genre tests and see how it handles.
enjoy
-Drew
Replies (9)
newB on 01/18/2008 21:59:36
i just realized the sketchup drawing doesn't have specs-
http://i40.photobucket.com/albums/e216/saxwonder05/audio/ABC4.jpg
there is a slight typo- it shows 1.7cuft when really its 1.6
-Drew
Ash on 01/19/2008 04:29:04
You better watch that creativity! I hear Bose is a nasty mutha to deal with...... LOL!
How about a good description of the tonal quality, advantages, and drawbacks so far....
newB on 01/19/2008 04:43:34
Tonal Quality in general is deep, "fat" the kind of sound that makes you feel like your swimming. just by listening to music, as far as response curve (by ear) it seems similar to a 6th order bandpass curve, VERY strong and present from 50 or so down with a steep roll off around 25hz (by ear) i was getting a small amount of port noise when the box was in my car, directly behind the drivers seat, possibly due to the arrangement of the ports or maybe because I'm using 3inch ports, but when the box was placed in the customers trunk it was impossible to hear.(port noise that is)
quite frankly it sounds like it has two tuning frequencies. we were getting trunk, roof, and steering wheel rattle from a single 10 in this box (just below 30hz) i might try and pull off some some Pete style response vids of people realizing its only a single ten (i had a hilarious one on the first day)
MORE tests, and a video or two tomorrow!!
-Drew
swez on 01/19/2008 10:56:10
Interesting plan here Drew. This is similar to a 6th order BP with the benefit of more direct cone radiation in the upper bass region. (60-100 Hz.)
Another neat feature is the dual chambers and porting nodes in each segment of the box. The larger ported section reinforces the deep, low bass and the smaller chamber gives a bit more bump at 40-60 Hz. Here, I would expect two bumps in a frequency sweep tone and SPL measurments where the ports are tuned in each chamber. (Not very musical, but lots of deep bump and some punch too)
Lastly, be mindful of the power fed to any woofer used in this design. There is little cone back pressure, (which meas) minimal excursion of the cone. That could easily fry a coil when using low power handling subs that are not able to cool themselves well under these conditions. It would be wise to use a very robust sub with above average heat dissapation characteristics.
Swez
newB on 01/19/2008 20:41:54
Right now its an Ascendant Audio Assassin 10inch woofer, which is a strong woofer but actually doesn't cool itself as well as i had hoped when buying it.
we're having no problems with excursion here- the single 10 doing 28hz is at full excursion, and stays moving a good deal throughout the range. i'm actually looking for a woofer with stiffer suspension right now, and better voice coil vents.
vids coming soon!!
-Drew
newB on 01/20/2008 02:34:07
OH NO!!!!!!!!!!!!!!!!!!!!
>_<
http://i40.photobucket.com/albums/e216/saxwonder05/DCTT3.jpg
http://i40.photobucket.com/albums/e216/saxwonder05/DCTT5.jpg
looks like now i gotta build THIS!!!
-Drew
swez on 01/20/2008 14:41:36
Interesting idea here too! (A dual tuned venting system)
One thing I don't get here, is the longer vent alignment. It's odd to see that overhanging panel lip at the right rear corner of the drawing??? It would seem like an obstruction or perhaps a wave guide that would cancel out unwanted bass nodes? Other than that, the longer vent will act like an acoustical wave guide or labyrinth type vent.
Like the rounded corners on each vent panel joint as this allows a smooth transition of bass as it passes through the venting system. This seems to be a nice variation of a 3 in 1, subwoofer enclosure.
1. Front cone bass radiation
2. Short port for lower midbass punch (What frequency is hard to say?)
3. Long port for deep bass tuning (Tuned well below 40 Hz. looks likely)
Neat and a very good challenge to any skilled enclosure builder. Lots of router work here too. (Use a carbide type half round bit on this one so you don't burn the wood or mangle a cheap bit.
Swez
newB on 01/20/2008 15:25:44
oh yeah i have a nice router with a good round bit that just destroys MDF corners.
this is how ive been designing these- how i was just taught its simple and easy to setup and sounds amazing so far.
"first start by selecting a standard ported alignment for the driver in question. Then, select two ports of equivalent length and diameter to tune the system to the required frequency. Split the required volume for the alignment into two, placing one port in the smaller chamber (1/3 total volume), and the other port and driver in the larger chamber (2/3 total volume). Finally, join the two chambers together with a port that's the same size and length as the ports used to vent the chambers to the outside."
All three ports, (1:out large chamber 2:connecting chambers 3:out small chamber) are ALL the same lengthxwidth what changes the tuning frequency is the size of the chamber they are comming from.
-Drew
newB on 01/20/2008 15:28:19
oh and on the second Slot Vent Style, if i remember correctly the high port is ~44hz and the low tuned is ~30hz its the same box that i have already built but in a slot vent with ~15sqin of port instead of the aero port style 7sqin.
-Drew
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