Subwoofer size and box help

LEOopasni2709

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Dec 3, 2020
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Hi, I am looking for subwoofer and amp and in my budget, based by reviews and what is available in my country I will most propably go with Focal P25 DB (10inch) or P30 DB (12inch). Amp will be Alpine MRV-M250 mono (D class) or MRV-V500 5 channel (D class) so i can connect front speakers too. I will parralel connect 2x4 Ohm coils so i get 2 Ohm output. Both amps produce 250W RMS continious at 2 Ohms. Focal P25 DB is rated at 250W, while P30 DB is rated at 300W. Suggested sealed box size for 10 inch is from 15-35L so middleground would be 25L, and for 12 inch is from 25-45L so middleground would be 35L. I mostly listen to 90s hip hop, rock sometimes jazz, EDM and techno. I want bass to be SQ oriented and full (I dont need to rattle the car to pieces). So will I get more out of 10inch 250W in 25L or even 35L box using its full potetial with 250W amp or will 12inch 300W in 35L box give a bit lower bass for hip hop regardless of not pushing full 300W to it Thank you :)







Here are the links to all technical details
 
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1aespinoza

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May 22, 2013
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Here are the links to all technical details
Go with the 12" but ported. Sealed is awesome for tight control, but it needs more power to play alot of the nuances from music that is not purposely bass heavy. Ported on the other hand, plays well with lower power so your bass line will be louder at any volume. Also, at those power levels, you do not have to worry about erratic cone movement. So tight cone control will be acheived, which is the main feature in SQ oriented setups. It is imperative to build the box to manufacturer specifications.
 
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LEOopasni2709

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Dec 3, 2020
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Go with the 12" but ported. Sealed is awesome for tight control, but it needs more power to play alot of the nuances from music that is not purposely bass heavy. Ported on the other hand, plays well with lower power so your bass line will be louder at any volume. Also, at those power levels, you do not have to worry about erratic cone movement. So tight cone control will be acheived, which is the main feature in SQ oriented setups. It is imperative to build the box to manufacturer specifications.
Thank you, well, box will definitely be by manufacter specifications as they listed on Focal website. I was just asking myself If I will get some noticable difference in 10 vs 12 with given setup
 

1aespinoza

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May 22, 2013
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noticable difference in 10 vs 12 with given setu
Given the same wattage, you will definitely hear more output out of a 12 vs a 10. As to the 12 having a higher RMS value being an impediment in performance? No. Standard practice amongst builders is to use the same voice coil in the 10, 12, and 15 in the same line-up. Why the 12 is rated higher I have no clue. But 50w is no biggie.
On another note, if sacrificing space has you on the fence, then IMO, go with the 10. No use in making the sacrfice a point of contention when the need arises. It will still sound good regardless.
 
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hispls

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Thank you, well, box will definitely be by manufacter specifications as they listed on Focal website. I was just asking myself If I will get some noticable difference in 10 vs 12 with given setup
All things being equal go with the largest diameter driver you can provide enough airspace for. 10" woofer in proper box volume will outperform 12" driver in too-small box, but the larger woofer will give you more output at the same power meaning you won't need to push it as hard to get whatever level of output you need.

Keep in mind some woofers are designed to play in sealed box and some are designed to function best in ported boxes. Use whichever the manufacturer recommends and if they have a range of box sizes I'd lean towards using the larger ones.

Why the 12 is rated higher I have no clue.
Probably because the "power handling" rating takes into account mechanical limits. The smaller cone will try to move farther than the 12" cone and would likely bottom out off of less power.
 

LEOopasni2709

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Dec 3, 2020
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Given the same wattage, you will definitely hear more output out of a 12 vs a 10. As to the 12 having a higher RMS value being an impediment in performance? No. Standard practice amongst builders is to use the same voice coil in the 10, 12, and 15 in the same line-up. Why the 12 is rated higher I have no clue. But 50w is no biggie.
On another note, if sacrificing space has you on the fence, then IMO, go with the 10. No use in making the sacrfice a point of contention when the need arises. It will still sound good regardless.
Oh, no worries for space, I have it enough for reccomended box specs. by Focal. And I can say I dont use trunk at all...in last two years most I put inside was few backpacks:LOL:
 

LEOopasni2709

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Dec 3, 2020
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All things being equal go with the largest diameter driver you can provide enough airspace for. 10" woofer in proper box volume will outperform 12" driver in too-small box, but the larger woofer will give you more output at the same power meaning you won't need to push it as hard to get whatever level of output you need.

Keep in mind some woofers are designed to play in sealed box and some are designed to function best in ported boxes. Use whichever the manufacturer recommends and if they have a range of box sizes I'd lean towards using the larger ones.


Probably because the "power handling" rating takes into account mechanical limits. The smaller cone will try to move farther than the 12" cone and would likely bottom out off of less power.
Well, Focal says both ported and sealed work and give the specs for both. I have heard some ported and sealed boxes, but I kind of lean to sealed, I personally think it will suit me better for what I want from subwoofer. But also on the other side who knows how well were those ported boxes executed, those guys who I heard them from dont even care about adjusting front stage, crossovers...let alone care about box and port size.
 

hispls

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Sep 10, 2009
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Well, Focal says both ported and sealed work and give the specs for both. I have heard some ported and sealed boxes, but I kind of lean to sealed, I personally think it will suit me better for what I want from subwoofer. But also on the other side who knows how well were those ported boxes executed, those guys who I heard them from dont even care about adjusting front stage, crossovers...let alone care about box and port size.
Try the sealed then. If you feel you're lacking low end extension you might try to build a ported box to give you a little more output down low.
 
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