I have done some digging into putting subs into the tj. I wasnt sure if this should go into builds or here. I will move it if need be.
There are viable options for 8in subs in center console.
There are viable options for under seat subs for the back seat.
I decided to go 5 channel amp for centralized control and space saving.
Polk pad5000.5
Upgraded speakers for dash and sound bar.
Polk db522 with dash pods
And polk db65 in sound bar
I chose polk due to power and fitment offerings as well as marine rating since I will be spending some time with the top off.
Now planning entails the 500rms sub woofer channel.
Also most entry 12" subs require 1.5cuft of sealed enclosure space and most entry 15" require 1.75cuft.
As we know there is limited "trunk" space. So I could keep my tuffy cargo area divider thing. It is nice. It would hid a sub box as well as ensures room to get hands in to remove fold down back seat. However only allows for a sealed 12" sub and not enough for 1 15". Outside dimensions 27.5 wide x base depth 11" x top depth 8" x 12"h
For roughly 1.26 cuft barely enough for one 10" or 12". One could add spacer under tuffy cover to give an extra inch height to the box. For 1.38cuft.
Or remove the tuffy cover and there is enough room to build a sealed trapezoidal box that could house 2 15" subs but not 3 12".
Outside dimensions 33" wide x base depth 11" x top depth 7" x 28"h for 3.51 cuft. This accounts for divider bracing but not volume taken up by sub which about 0 .3cuft.
I know I am working with little power. However, based on some research, cone area is a great factor than excursion and a properly matched amp power to sub rms will provide optimal sound and longevity. I also have looked into cone area versus power or motor force. So say 2 15" at 250 watt rms or 1 12" or 1 15" at 500 watt rms. And the above statement seems to hold true with a good pairing of amp rms and speaker rms the 2 15" at 250 rms 500w total power are best.
https://ddaudio.com/tech-talk-important-getting-max-spl-cone-area-motor-force/
https://www.stevemeadedesigns.com/board/topic/213830-excursion-vs-cone-area/
As chart I grabbed from diyadudio
Show total cone area of when using multiple of respective sub sizes.
Also on eclosures:
Generally proper size sealed boxes take up less space and provide better sound quality At a marginal cost to SPL or "volume"
Ported boxes require more space provide more spl at marginal cost of sound quality
Also when building an enclosure that is "just big enough" polyfill is a viable option for "increasing percieved enclosure volume".
Below is a box volume calculator tool that is may help with all your future endeavors.
https://rockfordfosgate.com/support/box-wizard/
I hope this saves some time for those of you looking to fit subs and upgrade car audio. There is alot of "info" out there.
My take aways from these and many other less informative reads is.
Properly sized enclosure is priority for optimal subwoofer performance. 2 adqueately power subs in an improperly sized enclosure will have poor sound quality and may even under perform 1 of the same exact brand model adequatley powered subwoofers in a properly sized enclosure.
Properly driven Cone area will ,typically not always, out weigh excursion and motor force when amp power is limited. in spl and sound quality.
And polyfill in a .5-1.5 lb per cuft or approx 30% volume will make a a subwoofers percieved box volume and thus improve sound quality and make less work on sub for a given enclosure of minimum adequate volume.
This sound system is going to be 4 - 2 way polk db series marine speakers and 2 rockford fosgate p1 250watt rms. Powered by polk pad5000.5 4 channel 100w rms and sub channel 500w rms.
There are issues of amp headroom and it may leave amp working too hard using all 500w of rms. In which case I may back down to a smaller encloser and 1 15" or an even smaller enclosure and 1 12".
Currently the 2 15" rockford fosgate p1 in a trapezoidal sealed box that is 33 wide x 11 base depth x 7 top depth x by 28 high is the plan. This pokes up 4" above the top of the back seat.
2 12" would do well in a 33"x11"bdx8"tdx24"h which give 3.18 including divider brace. This would come up to top of back seat.
Will post update.
I am looking into hdpe enclosure build as well as mdf weather treating. I will update once i find out more.
There are viable options for 8in subs in center console.
There are viable options for under seat subs for the back seat.
I decided to go 5 channel amp for centralized control and space saving.
Polk pad5000.5
Upgraded speakers for dash and sound bar.
Polk db522 with dash pods
And polk db65 in sound bar
I chose polk due to power and fitment offerings as well as marine rating since I will be spending some time with the top off.
Now planning entails the 500rms sub woofer channel.
Also most entry 12" subs require 1.5cuft of sealed enclosure space and most entry 15" require 1.75cuft.
As we know there is limited "trunk" space. So I could keep my tuffy cargo area divider thing. It is nice. It would hid a sub box as well as ensures room to get hands in to remove fold down back seat. However only allows for a sealed 12" sub and not enough for 1 15". Outside dimensions 27.5 wide x base depth 11" x top depth 8" x 12"h
For roughly 1.26 cuft barely enough for one 10" or 12". One could add spacer under tuffy cover to give an extra inch height to the box. For 1.38cuft.
Or remove the tuffy cover and there is enough room to build a sealed trapezoidal box that could house 2 15" subs but not 3 12".
Outside dimensions 33" wide x base depth 11" x top depth 7" x 28"h for 3.51 cuft. This accounts for divider bracing but not volume taken up by sub which about 0 .3cuft.
I know I am working with little power. However, based on some research, cone area is a great factor than excursion and a properly matched amp power to sub rms will provide optimal sound and longevity. I also have looked into cone area versus power or motor force. So say 2 15" at 250 watt rms or 1 12" or 1 15" at 500 watt rms. And the above statement seems to hold true with a good pairing of amp rms and speaker rms the 2 15" at 250 rms 500w total power are best.
https://ddaudio.com/tech-talk-important-getting-max-spl-cone-area-motor-force/
https://www.stevemeadedesigns.com/board/topic/213830-excursion-vs-cone-area/
As chart I grabbed from diyadudio
Show total cone area of when using multiple of respective sub sizes.
Also on eclosures:
Generally proper size sealed boxes take up less space and provide better sound quality At a marginal cost to SPL or "volume"
Ported boxes require more space provide more spl at marginal cost of sound quality
Also when building an enclosure that is "just big enough" polyfill is a viable option for "increasing percieved enclosure volume".
https://rockfordfosgate.com/support/box-wizard/
I hope this saves some time for those of you looking to fit subs and upgrade car audio. There is alot of "info" out there.
My take aways from these and many other less informative reads is.
Properly sized enclosure is priority for optimal subwoofer performance. 2 adqueately power subs in an improperly sized enclosure will have poor sound quality and may even under perform 1 of the same exact brand model adequatley powered subwoofers in a properly sized enclosure.
Properly driven Cone area will ,typically not always, out weigh excursion and motor force when amp power is limited. in spl and sound quality.
And polyfill in a .5-1.5 lb per cuft or approx 30% volume will make a a subwoofers percieved box volume and thus improve sound quality and make less work on sub for a given enclosure of minimum adequate volume.
This sound system is going to be 4 - 2 way polk db series marine speakers and 2 rockford fosgate p1 250watt rms. Powered by polk pad5000.5 4 channel 100w rms and sub channel 500w rms.
There are issues of amp headroom and it may leave amp working too hard using all 500w of rms. In which case I may back down to a smaller encloser and 1 15" or an even smaller enclosure and 1 12".
Currently the 2 15" rockford fosgate p1 in a trapezoidal sealed box that is 33 wide x 11 base depth x 7 top depth x by 28 high is the plan. This pokes up 4" above the top of the back seat.
2 12" would do well in a 33"x11"bdx8"tdx24"h which give 3.18 including divider brace. This would come up to top of back seat.
Will post update.
I am looking into hdpe enclosure build as well as mdf weather treating. I will update once i find out more.
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