I currently am running a sealed 12w6v2 for my SQ setup but im really curious to try 2 12w6v2's for a SQL setup.
What do you guys think about this box i ran across online ?
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=3638
It doesnt mention what the box is tuned to.
Im thinking about going 34-35hz 4" inner diamater port but im not sure if that is what its tuned to.
I see its 2 cuft per chamber which sounds right for a 12" subwoofer these days.
Now keep in mind that i plan to use my JL 500/1 to power this with which is why i thought of ported for efficiancy etc..
I think this will be fun. Your thoughts ?
Replies (13)
MO on 01/13/2007 00:41:32
I believe it whould be better at 4" ID ports per sub. Doesnt look like it in the picture.
swez on 01/13/2007 02:07:43
Tough call on this box MO. It seems to have a 4-5" port, shared between 2 chambers. That cuts the port diameter by half to each chamber.
Ran this through a port calculator just to see what it might be tuned for. It looks like this one is tuned between 20-27 Hz.
2.0" ID port, 9.0" long, Fb = 2.0 cf: About 20 Hz.
4.0" ID port, 9.0" long, Fb = 4.0 cf: About 26.5 Hz.
Interesting way of porting here,
Swez
MO on 01/13/2007 11:59:51
Yeah ill pass on that box swez. What do you suggest here.
Im thinking 2.0 cuft per sub and 4 inch diameter ports per sub.
Should i use seperate chambers ?
To get 35hz i whould need about 9" or so im sure of port length.
Let me know your thoughts and suggestions on this sql setup.
swez on 01/13/2007 13:58:25
Frankly, since we are talking JL woofers, who better to know the optimal parameters for their woofers and amps? Read this and print a copy for references:
http://mobile.jlaudio.com/pdfs/7876.pdf
Page 2 lists the specs of a ported box recommendation for their 12W6 series subs. They chose a slot vent type port to allow a sub to breath and minimize port noise issues and such.
Note: The 1.5 cf is Vb, (internal airspace, subtracting vent and speaker displacements) is what Vb means. Not sure what the tuning freaquency for this alignment is, but you can contact JL for that spec.
Have a look at the box dimensions they give and see if this will fit into your vehicle. With a ported design,we can expect about +3dB more bass at and slightly above PTF. (Port Tuning Frequency) That is the same as doubling the input wattage for a single 12W6. (sealed)
IMHO, I would hold off on purchasing a 2nd woofer and just build a ported box for your present sub. You'll note a good bump in SPL near PTF, the sub will be more efficient and saves you a notable expense.
If you find later that you want even more bass, then consider adding an identical sub kit and move up to the 1000/1, (Or a second 500/1) to power them both to full potential.
Tech Tip: Since you have a very large trunk in this car, you may want to consider fabricating an air vent to pass more bass energy from the trunk, to the interior cabin. To test this, just remove the rear deck speakers and note the bass presents you'll get inside the cabin. In this case, it should be very noticable how much more bass presents comes into the cabin. Based on that, then you can decide what to do next.
Comments?
Swez
MO on 01/13/2007 14:08:39
Here is what a friend said :
"mo I have one 10w6v2 with 500/1 on it and its about perfect, if you get a 12w7 I suggest a 1000/1 to push it, same with those 12w6v2's more power, jl always underrate their stuff, also iI built three boxes for this 10w6v2, one sealed to spec (ok but not great, one ported to spec (much better but to high hz) then I built one 10% oversized with 5" less on the port (tuned to about 35hz) and whoa it slams.
I plan to listen to mostly RAP and Dance and a bit of ROCK music.
What tuning do you recommend for me ?
I understand JL recommends 1.5 cuft net @ ?
swez on 01/13/2007 15:39:50
"What tuning do you recommend for me" ?
Here, 30-35 Hz., tuning is very good. You'll get lots of deep lows for Rap here. Dance and Rock generally don't go much below 40 Hz. So, that tuning point should be very solid as well.
"I understand JL recommends 1.5 cuft net @" ?
Jargon clarified:
Vb = usable airspace inside an enclosure, after we subtract the "air displacement" of the subwoofer and port. JL recommends a Vb of 1.5 cf of usable airspace when one subtracts woofer displacement, (0.09 cf/woofer) and port displacement. (~0.47 cf)
If we look at the JL recommendations, the overall internal air space of the recommended box is 2.06 cf. (internally) Pretty close to your original target of 2.0 cf yes? YES
Then we subtract sub and port displacements to get the actual internal airspace that remains for the sub to work within:
2.06 cf - 0.09 cf (sub disp) - 0.47 cf (port displacement) = Vb = 1.5 cf.
Got all that now?
Swez
MO on 01/13/2007 17:17:31
I understand the enlcosure size but whould i be better of tuning this enclosure to 35hz since i listen to alot of dance and rap and rock ? Perhaps 1.75-2.0 @ 35hz whould be what im after ?
Or should i tune a bit higher or lower ?
cplkittle on 01/13/2007 20:41:45
It is all about preference. A sealed box gives you tight bass, we all know that, and a ported gives you low bass at the expence of accuracy. Well, there is also a tight bass and a low bass ported box. The bigger the box the thicker and boomier bass, the smaller the box, the tighter the bass, but the bass loses body or fullness.
I had a customer in an expedition that wanted the thunder in the song by Garth Brooks 'The thunder rolls' to sound like real thunder. I put 2 12s in a 4 cuft. box tuned to 33, and he got exactly what he wanted and then some.
Some call these extended bass shelf boxes, by definition they aren't quite, but by style I guess they could be considered that.
Anyway, what I am getting at is that there are alot of variables that can change the sound. What exactly are you looking for in your bass?
thick heavy bass = bigger box
deeper bass = lower tuned frequency
louder, but accurate = smaller box, higher tuned frequency
pure spl = smaller box, very high frequency (~46 Hz)
swez on 01/13/2007 20:51:44
For car audio applications, most tune between 30-35 Hz. Since your taste in music is a bit broader than some, 35 Hz is a good target. You'll get a nice bump in SPL at 35 to about 45 Hz. From there, the cone takes over and the boost from porting drops away and output is similar to a sealed box up to your crossover point.
Swez
MO on 01/13/2007 23:00:03
Im looking for louder but accurate. I dont like sloppy bass that misses notes. I whould like to feel the kick drums in rock and the rap bass notes with authority and feel the punch in my chest. Im not so crazy about deep bass such as 30hz and lower.
Again i listen to mostly rap and dance and rock.
What do you think cplkittle or swez ?
cplkittle on 01/14/2007 00:47:37
You can go a little bigger, not double like the example I gave before. If the recommended specs are 1.75-2.0 You could go up to 2.25 maybe even 2.5. I would not go below 33Hz. It is going to be difficult to hear much if this is going in the crown vic. They are aggravating cars for bass. The back seat and back deck seem to muffle out alot of bass.
You could change any factor (tuning, box size) by 10% and I don't think I could tell the difference by ear, so precision is not as much of a necessity as you might think.
MO on 01/14/2007 02:19:04
Here is what is recommended exactly :
http://mobile.jlaudio.com/products_subs_enclusure.php?series_id=4
1.5 net @ 32hz
swez on 01/14/2007 09:42:28
Yep, that spec will give very good deep lows as specified.
As Kit mentioned, this car will muffle the punchy bass w/o some form of pass through vent (opening) into the cabin of this car. A fully sealed trunk in any large sedan, acts like a sound dampening cave. This meaning we hear low thumps, but clarity and crispness of bass is lost in the trunk as well as several dB of SPL.
FYI: One of my former clients had a 92 Lumina and dual 10's Alpine (sealed) SWR's, powered by a Alpine 600 RMS amp. Once he cut a pass through vent in the rear deck, he noted a very nice change in punch, very good deep lows and SPL was increased by almost +5 dB.
Several guys here scoffed at the plan, but he did it anyway. The results netted him some fine kuddos from the local "Snobshop" he had been nosing around at. For what that's worth...
Swez
What do you guys think about this box i ran across online ?
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=3638
It doesnt mention what the box is tuned to.
Im thinking about going 34-35hz 4" inner diamater port but im not sure if that is what its tuned to.
I see its 2 cuft per chamber which sounds right for a 12" subwoofer these days.
Now keep in mind that i plan to use my JL 500/1 to power this with which is why i thought of ported for efficiancy etc..
I think this will be fun. Your thoughts ?
Replies (13)
MO on 01/13/2007 00:41:32
I believe it whould be better at 4" ID ports per sub. Doesnt look like it in the picture.
swez on 01/13/2007 02:07:43
Tough call on this box MO. It seems to have a 4-5" port, shared between 2 chambers. That cuts the port diameter by half to each chamber.
Ran this through a port calculator just to see what it might be tuned for. It looks like this one is tuned between 20-27 Hz.
2.0" ID port, 9.0" long, Fb = 2.0 cf: About 20 Hz.
4.0" ID port, 9.0" long, Fb = 4.0 cf: About 26.5 Hz.
Interesting way of porting here,
Swez
MO on 01/13/2007 11:59:51
Yeah ill pass on that box swez. What do you suggest here.
Im thinking 2.0 cuft per sub and 4 inch diameter ports per sub.
Should i use seperate chambers ?
To get 35hz i whould need about 9" or so im sure of port length.
Let me know your thoughts and suggestions on this sql setup.
swez on 01/13/2007 13:58:25
Frankly, since we are talking JL woofers, who better to know the optimal parameters for their woofers and amps? Read this and print a copy for references:
http://mobile.jlaudio.com/pdfs/7876.pdf
Page 2 lists the specs of a ported box recommendation for their 12W6 series subs. They chose a slot vent type port to allow a sub to breath and minimize port noise issues and such.
Note: The 1.5 cf is Vb, (internal airspace, subtracting vent and speaker displacements) is what Vb means. Not sure what the tuning freaquency for this alignment is, but you can contact JL for that spec.
Have a look at the box dimensions they give and see if this will fit into your vehicle. With a ported design,we can expect about +3dB more bass at and slightly above PTF. (Port Tuning Frequency) That is the same as doubling the input wattage for a single 12W6. (sealed)
IMHO, I would hold off on purchasing a 2nd woofer and just build a ported box for your present sub. You'll note a good bump in SPL near PTF, the sub will be more efficient and saves you a notable expense.
If you find later that you want even more bass, then consider adding an identical sub kit and move up to the 1000/1, (Or a second 500/1) to power them both to full potential.
Tech Tip: Since you have a very large trunk in this car, you may want to consider fabricating an air vent to pass more bass energy from the trunk, to the interior cabin. To test this, just remove the rear deck speakers and note the bass presents you'll get inside the cabin. In this case, it should be very noticable how much more bass presents comes into the cabin. Based on that, then you can decide what to do next.
Comments?
Swez
MO on 01/13/2007 14:08:39
Here is what a friend said :
"mo I have one 10w6v2 with 500/1 on it and its about perfect, if you get a 12w7 I suggest a 1000/1 to push it, same with those 12w6v2's more power, jl always underrate their stuff, also iI built three boxes for this 10w6v2, one sealed to spec (ok but not great, one ported to spec (much better but to high hz) then I built one 10% oversized with 5" less on the port (tuned to about 35hz) and whoa it slams.
I plan to listen to mostly RAP and Dance and a bit of ROCK music.
What tuning do you recommend for me ?
I understand JL recommends 1.5 cuft net @ ?
swez on 01/13/2007 15:39:50
"What tuning do you recommend for me" ?
Here, 30-35 Hz., tuning is very good. You'll get lots of deep lows for Rap here. Dance and Rock generally don't go much below 40 Hz. So, that tuning point should be very solid as well.
"I understand JL recommends 1.5 cuft net @" ?
Jargon clarified:
Vb = usable airspace inside an enclosure, after we subtract the "air displacement" of the subwoofer and port. JL recommends a Vb of 1.5 cf of usable airspace when one subtracts woofer displacement, (0.09 cf/woofer) and port displacement. (~0.47 cf)
If we look at the JL recommendations, the overall internal air space of the recommended box is 2.06 cf. (internally) Pretty close to your original target of 2.0 cf yes? YES
Then we subtract sub and port displacements to get the actual internal airspace that remains for the sub to work within:
2.06 cf - 0.09 cf (sub disp) - 0.47 cf (port displacement) = Vb = 1.5 cf.
Got all that now?
Swez
MO on 01/13/2007 17:17:31
I understand the enlcosure size but whould i be better of tuning this enclosure to 35hz since i listen to alot of dance and rap and rock ? Perhaps 1.75-2.0 @ 35hz whould be what im after ?
Or should i tune a bit higher or lower ?
cplkittle on 01/13/2007 20:41:45
It is all about preference. A sealed box gives you tight bass, we all know that, and a ported gives you low bass at the expence of accuracy. Well, there is also a tight bass and a low bass ported box. The bigger the box the thicker and boomier bass, the smaller the box, the tighter the bass, but the bass loses body or fullness.
I had a customer in an expedition that wanted the thunder in the song by Garth Brooks 'The thunder rolls' to sound like real thunder. I put 2 12s in a 4 cuft. box tuned to 33, and he got exactly what he wanted and then some.
Some call these extended bass shelf boxes, by definition they aren't quite, but by style I guess they could be considered that.
Anyway, what I am getting at is that there are alot of variables that can change the sound. What exactly are you looking for in your bass?
thick heavy bass = bigger box
deeper bass = lower tuned frequency
louder, but accurate = smaller box, higher tuned frequency
pure spl = smaller box, very high frequency (~46 Hz)
swez on 01/13/2007 20:51:44
For car audio applications, most tune between 30-35 Hz. Since your taste in music is a bit broader than some, 35 Hz is a good target. You'll get a nice bump in SPL at 35 to about 45 Hz. From there, the cone takes over and the boost from porting drops away and output is similar to a sealed box up to your crossover point.
Swez
MO on 01/13/2007 23:00:03
Im looking for louder but accurate. I dont like sloppy bass that misses notes. I whould like to feel the kick drums in rock and the rap bass notes with authority and feel the punch in my chest. Im not so crazy about deep bass such as 30hz and lower.
Again i listen to mostly rap and dance and rock.
What do you think cplkittle or swez ?
cplkittle on 01/14/2007 00:47:37
You can go a little bigger, not double like the example I gave before. If the recommended specs are 1.75-2.0 You could go up to 2.25 maybe even 2.5. I would not go below 33Hz. It is going to be difficult to hear much if this is going in the crown vic. They are aggravating cars for bass. The back seat and back deck seem to muffle out alot of bass.
You could change any factor (tuning, box size) by 10% and I don't think I could tell the difference by ear, so precision is not as much of a necessity as you might think.
MO on 01/14/2007 02:19:04
Here is what is recommended exactly :
http://mobile.jlaudio.com/products_subs_enclusure.php?series_id=4
1.5 net @ 32hz
swez on 01/14/2007 09:42:28
Yep, that spec will give very good deep lows as specified.
As Kit mentioned, this car will muffle the punchy bass w/o some form of pass through vent (opening) into the cabin of this car. A fully sealed trunk in any large sedan, acts like a sound dampening cave. This meaning we hear low thumps, but clarity and crispness of bass is lost in the trunk as well as several dB of SPL.
FYI: One of my former clients had a 92 Lumina and dual 10's Alpine (sealed) SWR's, powered by a Alpine 600 RMS amp. Once he cut a pass through vent in the rear deck, he noted a very nice change in punch, very good deep lows and SPL was increased by almost +5 dB.
Several guys here scoffed at the plan, but he did it anyway. The results netted him some fine kuddos from the local "Snobshop" he had been nosing around at. For what that's worth...
Swez
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