Hi,
I want to choose a 15 inch driver for small sealed box (30 liters). Can you please suggest what technical parameters I should be looking for?
I plan to use a small box, equalize using LT and use a higher power about 600 watts.
Note:-I understand Hoffman Iron law.
Thanks and Regards,
WA
I want to choose a 15 inch driver for small sealed box (30 liters). Can you please suggest what technical parameters I should be looking for?
I plan to use a small box, equalize using LT and use a higher power about 600 watts.
Note:-I understand Hoffman Iron law.
Thanks and Regards,
WA
What low-frequency cut-off frequency are you aiming for?
The 30-litre volume also seems to be very small for a 15-inch driver. For example, the gross volume of one 13-inch sealed commercial subwoofer is 61 litres.
The 30-litre volume also seems to be very small for a 15-inch driver. For example, the gross volume of one 13-inch sealed commercial subwoofer is 61 litres.
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You'll need either a very low Qt prosound driver (very efficient) or very low Vas (very inefficient) driver such as often used in mobile audio apps or a mix of the two.
Yeah, my Polk Audio shallow mount 15's required 1.5ft3 (42.5L).
RECOMMENDED SEALED ENCLOSURES
MM840 & MM840DVC 0.35 cu ft (9.9L)
MM1040 & MM1040DVC 0.66 cu ft (18.7L)
MM1240 & MM1240DVC 0.88 cu ft (24.9L)
MM1540 & MM1540DVC 1.5 cu ft (42.5L)
After a quick calculation, an enclosure that's 44x44x35cm with 2.5cm panel thickness comes to about 45.6 litres of internal volume. The woofer will take up some of that volume, as will the plate amplifier powering the subwoofer. Net volume without stuffing will be a bit less than the empty air volume. That matches approximately with the Polk MM1540 recommended 42.5-litre enclosure size, where the driver was designed to be used in a sealed box.
For 30L sealed, it doesn't get better and cleaner than this driver. Eq at will, but give it 2kw
This beats up 15s without losing note sweetness
https://www.jlaudio.com/products/12w7ae-3-car-audio-w7ae-subwoofers-92115
This beats up 15s without losing note sweetness
https://www.jlaudio.com/products/12w7ae-3-car-audio-w7ae-subwoofers-92115
Here are some exploratory feasibility studies of various designs using the Polk MM1540 15-inch woofer.
In the manufacturer-recommended 45-litre sealed enclosure, the following low-frequency response is produced:
Reducing the enclosure volume to 30 litres and adding a Linkwitz Transform EQ produces the following. The f3 point is reduced by 12.3Hz, and the power required at 20Hz is about 650W.
Reducing the enclosure volume to 30 litres and adding an LP Shelf EQ produces the following results. The f3 point is reduced by 11.9Hz, and the power required at 20Hz is about 600W.
In the manufacturer-recommended 45-litre sealed enclosure, the following low-frequency response is produced:
Reducing the enclosure volume to 30 litres and adding a Linkwitz Transform EQ produces the following. The f3 point is reduced by 12.3Hz, and the power required at 20Hz is about 650W.
Reducing the enclosure volume to 30 litres and adding an LP Shelf EQ produces the following results. The f3 point is reduced by 11.9Hz, and the power required at 20Hz is about 600W.
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Ayyyyyy indeed. More exy here in Australia. I put gen1 in my boot 25yrs ago. Too expensive now, and intuition says the ZXI that I am messing with will be more defined than this
30 liters is a 10" speaker enclosure
Subs that work in small places
trade off efficiency.
Basically many car subs will do it.
Better to call them very very muddy woofers
since it wont be a sub regardless of EQ.
For accuracy and actual sound quality.
The speaker suspension wants a certain sized box.
otherwise it sounds like blurry bloomy
over EQ'd mush.
Something pretty graphs in sim wont tell you.
For more efficiency likely move up to 45 to 50 liters
with a 12"
I ran 12" subs sealed in a car with 35 to 40 liters each.
Somewhat misleading for home application.
Since response in a car is much deeper from
" cabin" loading. Efficiency goes up as well.
No were close to 600 watts, more like 150 watts
with a pair. With one woofer turned off.
It was not satisfying, even in small space.
Using EQ boost hit distortion on big dynamics.
Countless threads on here using the common
Dayton subs sealed. Corner loading
would be good in home.
If assuming you need 600 watts
your gonna need 2 subs.
Subs that work in small places
trade off efficiency.
Basically many car subs will do it.
Better to call them very very muddy woofers
since it wont be a sub regardless of EQ.
For accuracy and actual sound quality.
The speaker suspension wants a certain sized box.
otherwise it sounds like blurry bloomy
over EQ'd mush.
Something pretty graphs in sim wont tell you.
For more efficiency likely move up to 45 to 50 liters
with a 12"
I ran 12" subs sealed in a car with 35 to 40 liters each.
Somewhat misleading for home application.
Since response in a car is much deeper from
" cabin" loading. Efficiency goes up as well.
No were close to 600 watts, more like 150 watts
with a pair. With one woofer turned off.
It was not satisfying, even in small space.
Using EQ boost hit distortion on big dynamics.
Countless threads on here using the common
Dayton subs sealed. Corner loading
would be good in home.
If assuming you need 600 watts
your gonna need 2 subs.
I would dispute that. This 12" eats up 1000rms from a 1000/1 JLAudio amp (dyno tested on YouTube) daily for the past 25yrs with very hard basslines. Check the last page of the Which is louder thread. Its also available commercially built for home
This is a car sub driver
This is note perfect (@WhiteDragon , note that it's spelt note and not not)
Eq at will
30L sounds perfect for it. I have the gen1 in 35L 33Hz ported
Makes hi-fi sound boomy
Makes hi-fi sound like distorted mush
https://www.jlaudio.com/products/f112v2-gloss-home-audio-fathom-v2-powered-subwoofers-96141
https://www.jlaudio.com/pages/fathom®-v2
https://www.jlaudio.com/pages/gotham®-v2
https://stereo-magazine.com/review/jl-audio-gotham-v2-review
Its expensive but beats everything up with gorgeous authority
Sealed F3 wont be more than 55 Hz
Most people would just do the usual Lab12
or Dayton Reference or UM
Since they are less than 300 dollars each
and have higher sensitivity and lower Fs
Easier to do a pair since power needed wont be much more
200 watts
Having done multiple limited classes with single amp
and single alternator. I always beat the single super woofer
guys with 2x12 and not pulling wasted current with 2 ohm or 1 ohm loads.
Nothing was directed at your woofer recommendations.
I've just heard and built many over EQed systems over the years.
Being that there is many many well done 15" drivers
that have 18 to 20 Hz Fs.
I cannot recommend any for 30 liters.
Its hard enough to do with a 12" or a 10"
The LAB12 or Daytons basically want at least
40 to 55 Liters to approach SQ
Most people would just do the usual Lab12
or Dayton Reference or UM
Since they are less than 300 dollars each
and have higher sensitivity and lower Fs
Easier to do a pair since power needed wont be much more
200 watts
Having done multiple limited classes with single amp
and single alternator. I always beat the single super woofer
guys with 2x12 and not pulling wasted current with 2 ohm or 1 ohm loads.
Nothing was directed at your woofer recommendations.
I've just heard and built many over EQed systems over the years.
Being that there is many many well done 15" drivers
that have 18 to 20 Hz Fs.
I cannot recommend any for 30 liters.
Its hard enough to do with a 12" or a 10"
The LAB12 or Daytons basically want at least
40 to 55 Liters to approach SQ
Sounds like I am talking SQ and you are talking SPL. Put away the sine waves and play some real basslines as in the clips that I posted in the other thread, I took a lot of expense messing with both larger hi-fi as in Peerless, the spectrum of car audio and things like LAB12 clones to finally give in and try the lower efficiency subs from JL. They work when sound quality and a large output is important, and 30L is perfect for the 12. There is a large price to pay for all this but if you are as demanding as I am about the quality of tone, then give the W7 a go with your single alternator setup and for decent power at a very good price for home use, hang one of Erica.C's 600wrms monoblocks with integral mains PSU on each coil
You haven't tried everything until you have tried the 12W7 or 13W7. I have tried both sealed and ported. For my playlist, the ported box. I am still trying to understand why these drivers get so loud without losing any composure from such lil boxes
Hey man, for what it is worth. It's a pretty basic but specific SOR sans important details including basic use
I am sure the OP will find many who will say nah, can you be one to not do that too and take a closer look how to make it possible. It's all about exercising thought and seeking
Recommendations are serious based on personal experience as a demanding listener, presenter and most importantly as a customer, but I don't expect anyone to follow that due to the daunting price. I can't afford to replace this driver when it finally dies
That why I am messing with the ZR12.4D and ZXI12.4D. The datasheets have been messed up, disregard those. Side by side with the JL, they show a better build and in the right places to exceed performance. Your experience will actually help to sort these drivers out properly to find their potential for home and pro use. These might be the key to bringing down the box sizes for those that really need more compact
how can you put that 12 jl audio driver in such a small box without creating a super high Qtc? What does that sound like then (SQ)??? spike @ 50-60 hz in a high Q shape?
i dunno what a '1.6' damping factor sounds like but im sure youll point out the cabin gain will fill in below 50 hz nicely? is that still 'SQ'?
In a typical room corner it can sound fine depending on the XO point, i.e. calc its effective Fhm and XO 4LR. For OB it has worked fine with as high as 3.3+ Qt. Mobile audio OTOH really requires how well sealed it is 'in toto', which in my time was very lossy (wish I still had a pic of the dual Altec 18" filling the entire rear seats/trunk of a friend's '70 Camaro), but in my 2k Toyota Tundra V6 PU with upgraded sound system (no sub), just using a little bit of its bass tone control is all I need it's so 'quiet'.
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Yeah, I can't believe he's comparing that JL to a $99 speaker. I'll take 14 MM1540's over that one 12.
People do not put sealed enclosures in cars for SPL. Sealed enclosures in cars are strictly for convenient bass.
I've been running a single 12 in a BP4 enclosure with a 200 watt amp in my past 2 cars...same enclosure in both cars. My 30 year old son wants my car so we've been redoing the audio system. Even got a 240 amp alternator. I'm kinda salty I want be able to work on the car this weekend. I'm riding with my buddy right now to Savanah, GA to pick up a 2022 Camaro ZL1 1LE.