box size info IM NEW AND MUST HAVE MADE MISTAKE

[crlpsu610]

i bought some close out subs the dual 4 ohm 10" for 25$ each... i am new to speaker building but have a decent construction background and loads of wood tools ! my problem is when i typed in the info for the sub it comes back with a 9 cu ft enclosure..... is there any way to shrink that down and have it still work well ? I can't see a 10" sub needing that big of a box lol Im new so i must have messed up something lol here are the specs! Fs:27 Vas:3.15 cu ft QMS 9.83 Qes: 0.65 Qts:0.61 was thinking more like 1.5 -2 cu ft box i duno please help me lol thanks in advance, Clint

added details I have 4 of them i would like to use in my HT room the room is 10.5x23 ft x8 i have fully covered the ceiling and walls with fabric wrapped 2" fiberglass panels I plan on wireing them as a pair to gat 4 ohms each side placing them under my screen on top my stage witch is why im trying to keep size down ty again

PS not sure if it matters but the room is solid concrete construction 10" thick poured walls 8" thick concrete ceiling all sound treated with the listed above details i call it the bunker lol it was a rain cistern i had it cut open to use it it the whole under side of my garage 800$ for 220 sq ft ;)

http://www.parts-express.com/pe/show...number=299-106 link to the speakers!

[rogoll]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

i bought some close out subs the dual 4 ohm 10" for 25$ each... i am new to speaker building but have a decent construction background and loads of wood tools ! my problem is when i typed in the info for the sub it comes back with a 9 cu ft enclosure..... is there any way to shrink that down and have it still work well ? I can't see a 10" sub needing that big of a box lol Im new so i must have messed up something lol here are the specs! Fs:27 Vas:3.15 cu ft QMS 9.83 Qes: 0.65 Qts:0.61 was thinking more like 1.5 -2 cu ft box i duno please help me lol thanks in advance, Clint

Since these are dual voice coil (DVC) I need to know how you're going to wire them; series, parallel, only one coil, or o?e coil per channel.

[charlielaub]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

i bought some close out subs the dual 8 ohm 10" for 25$ each... i am new to speaker building but have a decent construction background and loads of wood tools ! my problem is when i typed in the info for the sub it comes back with a 9 cu ft enclosure..... is there any way to shrink that down and have it still work well ? I can't see a 10" sub needing that big of a box lol Im new so i must have messed up something lol here are the specs! Fs:27 Vas:3.15 cu ft QMS 9.83 Qes: 0.65 Qts:0.61 was thinking more like 1.5 -2 cu ft box i duno please help me lol thanks in advance, Clint

No worries!

Depending on the type of music you listen to and the room that you put it in, it could still sound just fine. Your program is following the rule that the system Q should be equal to 0.707 and assumes an empty box. But having Q > 0.707 is fine - up to about 0.9 is OK although I would not recommend anything higher. With a sealed box you can reduce the Q somewhat by adding about 1 lb of polyester stuffing (like "acousta stuff") per cubic foot. PE sells this or try pillow stuffing from a local craft shop. Adding stuffing has the added advantage of reducing the internal resonances of the box. Just make sure to keep the stuffing away from the cone - it should not be touching or rubbing on it.

Although you didn't really give enough specs to do proper modeling of the driver, I guesstimated the missing info based on the specs of another 10" driver. I think that a closed, stuffed box of 2 cubic feet would still result in nice performance. It should give you a Q of between 0.85 and 0.9 with Fb=43Hz and F3=36Hz. There is a slight hump in the upper bass of 1 dB and, combined with the highish Q, this will probably make it sound "warm" but that is not a bad thing. If you are careful where you place this in the room and the room isn't too large, you should get nice bass extension when you include the "room gain" that happens below about 30-40 Hz.

Good luck!

-Charlie

[crlpsu610]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

series to get 8ohm each and then wired together parallel to get 4 ohm i have four of them want to group in 2's

[rogoll]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

series to get 8ohm each and then wired together parallel to get 4 ohm i have four of them want to group in 2's

O.K., BassBox Lite gives me a closed box volume of 1.366 cubic feet, and a vented box volume of 1.313 cubic feet with a 3inch vent 8.105 long, although there are many, many different combinations that would work.

[charlielaub]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

Why don't you post the link to the product on PEs web site, or where ever you bought them. There is really some discrepancy between what I posted and what rogoll just posted. I'd like to see the full specs, especially whether they were for series of parallel connection of the voice coils.

-Charlie

[Chris Roemer]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

i bought some close out subs the dual 4 ohm 10" for 25$ each... i am new to speaker building but have a decent construction background and loads of wood tools ! my problem is when i typed in the info for the sub it comes back with a 9 cu ft enclosure..... is there any way to shrink that down and have it still work well ? I can't see a 10" sub needing that big of a box lol Im new so i must have messed up something lol here are the specs! Fs:27 Vas:3.15 cu ft QMS 9.83 Qes: 0.65 Qts:0.61 was thinking more like 1.5 -2 cu ft box i duno please help me lol thanks in advance, Clint

added details I have 4 of them i would like to use in my HT room the room is 10.5x23 ft x8 i have fully covered the ceiling and walls with fabric wrapped 2" fiberglass panels I plan on wireing them as a pair to gat 4 ohms each side placing them under my screen on top my stage witch is why im trying to keep size down ty again

With a Q of 0.61, these are meant to go sealed, not vented.

[rogoll]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

Why don't you post the link to the product on PEs web site, or where ever you bought them. There is really some discrepancy between what I posted and what rogoll just posted. I'd like to see the full specs, especially whether they were for series of parallel connection of the voice coils.

-Charlie

BTW, I guesstimated 9.25 for the diameter. Hopefully, some other members will chime in...however, I'd probably go with Charlie's suggestions over my own. I'm still relatively new myself.

[Guest]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

Personally, I wouldn't go under 3.-4.cf with this driver... it has a Qts of .61, but the Qms is really stiff!! It's real easy to end up with either "boomy" bass (box too large), or bass that lacks any detail (box too small) with woofers that have small/weak magnets; and are designed with _overly stiff Qms_ to compensate.
:D

[crlpsu610]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

ty for the help so far guys ! i wish i would have know half of this before i ordered these... i would have picked something that used a smaller box lol but now that i have them any creative ideas on boxes ? need to stay at 13" tall or less and 16" wide and no more then 24" deep ..... would a L shape work lol 24" deep then go up the wall alil ? not sure how that would affect sound.... at 13X16X24 out side dia .75 wood i have 2.1 cu ft ... if i need at least 3 or 4 i neee to get creative lol or sell these and get different one ... uggg lol 20/20 hind sight is such a ... ;)

[charlielaub]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

No worries!

Depending on the type of music you listen to and the room that you put it in, it could still sound just fine. Your program is following the rule that the system Q should be equal to 0.707 and assumes an empty box. But having Q > 0.707 is fine - up to about 0.9 is OK although I would not recommend anything higher. With a sealed box you can reduce the Q somewhat by adding about 1 lb of polyester stuffing (like "acousta stuff") per cubic foot. PE sells this or try pillow stuffing from a local craft shop. Adding stuffing has the added advantage of reducing the internal resonances of the box. Just make sure to keep the stuffing away from the cone - it should not be touching or rubbing on it.

Although you didn't really give enough specs to do proper modeling of the driver, I guesstimated the missing info based on the specs of another 10" driver. I think that a closed, stuffed box of 2 cubic feet would still result in nice performance. It should give you a Q of between 0.85 and 0.9 with Fb=43Hz and F3=36Hz. There is a slight hump in the upper bass of 1 dB and, combined with the highish Q, this will probably make it sound "warm" but that is not a bad thing. If you are careful where you place this in the room and the room isn't too large, you should get nice bass extension when you include the "room gain" that happens below about 30-40 Hz.

Good luck!

-Charlie

Thanks for posting the link to the driver info. I think that my approach above will still work fine, assuming the driver specs are accurate. 2 cubic feet stuffed with 2 pounds of polyester acoustic stuffing is about as small as I would try. If you want to err on the side of caution, just make it larger to lower the Q keeping the stuffing at 1 pound per cubic foot.

-Charlie

[Guest]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

ty for the help so far guys ! i wish i would have know half of this before i ordered these... i would have picked something that used a smaller box lol but now that i have them any creative ideas on boxes ? need to stay at 13" tall or less and 16" wide and no more then 24" deep ..... would a L shape work lol 24" deep then go up the wall alil ? not sure how that would affect sound.... at 13X16X24 out side dia .75 wood i have 2.1 cu ft ... if i need at least 3 or 4 i neee to get creative lol or sell these and get different one ... uggg lol 20/20 hind sight is such a ... ;)

If they were mine, I'd try an Aperiodic vent, especially with the smaller boxes. I don't have modeling software, but to me, your 2.1cf with Aperiodic vents would create a fair balance between response and tone/sound quality.

[crlpsu610]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

Aperiodic Closed Box ..... interesting ......... anyone else have info on this ? i read a bit about it sounded simple ..... but to be honest theses speakers take alot of box and may just save them for a better space.... and use them to play around Then buy some decent speakers that ill use less space thanks for everything you guys are a good bunch!

[Guest]

Re: box size info IM NEW AND MUST HAVE MADE MISTAKE

Aperiodic Closed Box ..... interesting ......... anyone else have info on this ? i read a bit about it sounded simple ..... but to be honest theses speakers take alot of box and may just save them for a better space.... and use them to play around Then buy some decent speakers that ill use less space thanks for everything you guys are a good bunch!

http://www.troelsgravesen.dk/cyclop.htm

Here's an interesting system using aperiodic vents... there are many more... but it's not a common form of bass loading.
Once I stop changing my mind on which drivers to use, I intend to build one... and learn more about it's design.
Sorry I can't offer any help.
:o