Stereo Integrity BM pre-order: almost $100 off each!
#166
06-15-2010, 11:10 AM
#167
06-21-2010, 03:07 AM
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Pre-fab boxes for slim 12s are not made, and none that will fit the BM. You will need to build your own box or have one built.
As far as the results with the BMs: I've had mine in for a few months now, and I still believe they are easily the best possible subwoofer that can fit under the rear seat without a lift, both in output and clarity.
As far as the results with the BMs: I've had mine in for a few months now, and I still believe they are easily the best possible subwoofer that can fit under the rear seat without a lift, both in output and clarity.
#170
06-21-2010, 05:04 PM
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But that box is the best option I've seen so far for pre-fab, nice find.
#171
06-21-2010, 06:17 PM
It could work. Airspace is a little high for 1 BM, so maybe install wood blocks on the inside to bring it down to around .55 or .6 cubes. My only other worry would be lack of excursion space between the cone and the floor.
But that box is the best option I've seen so far for pre-fab, nice find.
But that box is the best option I've seen so far for pre-fab, nice find.
Have you modeled these in WinISD? 2ft is a .7 alignment. Bigger is just closer. The BM in recommended box is simply taking advantage of what most manufactures do, which is count on cabin gain. Nothing wrong with it, if you must have a small box, but bigger is almost always better for sub enclosures.
Per Nick from SI:
Matt,
Qtc is a 1.2 in 0.5^3 sealed. You can place the driver in a larger enclosure if you absolutely have to, but power handling will go down substantially. In a car audio environment there is no reason to put the driver in a larger enclosure unless you want an over-exaggerated bottom end and greatly reduced power handling. In a vehicle, hitting your target F3 (it should be in/around the mid 40's) is the most important aspect. Qtc is valid for home applications, but not so much for cars due to the +12 dB/octave gain you get starting at approximately 45 Hz. In our modeler it shows a nice gradual slight <2 dB rise in the frequency response down to approximately 45 hz where the drivers response starts to fall off. In a car you won't hear the rise because transfer function takes over around that same area and you end up with a nice even frequency response.
And as Zach said, you really don't need any more depth behind the driver due to the venting at the outside edge. You can kind of see by the first picture of the back of the driver that Zach posted that the vents are curved and they extend from the inside of the outer basket roll to the outside of the basket roll.
Speaking of which, here is a link to the BM's web page where you can see the technical mounting data near the bottom of the page.
Qtc is a 1.2 in 0.5^3 sealed. You can place the driver in a larger enclosure if you absolutely have to, but power handling will go down substantially. In a car audio environment there is no reason to put the driver in a larger enclosure unless you want an over-exaggerated bottom end and greatly reduced power handling. In a vehicle, hitting your target F3 (it should be in/around the mid 40's) is the most important aspect. Qtc is valid for home applications, but not so much for cars due to the +12 dB/octave gain you get starting at approximately 45 Hz. In our modeler it shows a nice gradual slight <2 dB rise in the frequency response down to approximately 45 hz where the drivers response starts to fall off. In a car you won't hear the rise because transfer function takes over around that same area and you end up with a nice even frequency response.
And as Zach said, you really don't need any more depth behind the driver due to the venting at the outside edge. You can kind of see by the first picture of the back of the driver that Zach posted that the vents are curved and they extend from the inside of the outer basket roll to the outside of the basket roll.
Speaking of which, here is a link to the BM's web page where you can see the technical mounting data near the bottom of the page.
Basically, going slightly bigger (.70 less displacement) should take power handling to about 400w, while giving a bit better low end (below 45hz) with no other real problems. Over 1 cube you get into more bloating (yes, I have tried it with my BM) but a .6-.75 seems to really shine with about 180w on it in my BMW. Definitely not a pounder, but it works well with the rest of the setup.
#172
06-21-2010, 07:02 PM
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Only potential problem from more air is loss of power handling. It will increase efficiency, especially in the lower frequencies, which will help it play louder.
Have you modeled these in WinISD? 2ft is a .7 alignment. Bigger is just closer. The BM in recommended box is simply taking advantage of what most manufactures do, which is count on cabin gain. Nothing wrong with it, if you must have a small box, but bigger is almost always better for sub enclosures.
Have you modeled these in WinISD? 2ft is a .7 alignment. Bigger is just closer. The BM in recommended box is simply taking advantage of what most manufactures do, which is count on cabin gain. Nothing wrong with it, if you must have a small box, but bigger is almost always better for sub enclosures.
#173
06-21-2010, 11:07 PM
Exactly, which is why I don't really rely heavily on WinISD for mobile subwoofer modeling. I understand the only loss from added air is power handling with the BM, but a lot of people who read this particular forum are the type that want to throw lots of power at their subwoofer for maximum output. Just trying to point people in the right direction. I'd love to see somebody try that pre-fab box with a BM. I will admit I have a slight (+1) bump at 31Hz with my BMs, but my box has .46 cu ft chambers.
Fair enough. I have yet to find a sub I did not like in a larger than .707 alignment, but, as noted, not as important in a car. And, as noted, for power handling, you are spot on as well.
FWIW, I will be switching out to a Dayton HO 15 in my car as soon as I have time to play, so I will have some more perspective. we shall see how the SI stands up to a bigger sub. Also plan to install another Zapco DC amp to give the sub a bit more power.
Matt
#174
06-22-2010, 12:33 AM
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I eagerly await your review of the Dayton and comparison to the BM (with more power on it, of course). As soon as I get some extra cash I will be getting the HO 10 and building a .7 cu ft box tuned to 30Hz for underseat use in the F150, and probably putting it in my dad's 08 F150. I am just incredibly curious as to how well it will perform as a single 10 in the F150, and honestly I have a good feeling about it. This may be on hold for a while though, next step is still the MS8.
WinISD calls for ~1.3 cubes for each Adire Koda 10". I had them in .7 each with fill, and they played extremely well and relatively flat to ~25Hz under the seat in the F150.
WinISD calls for ~1.3 cubes for each Adire Koda 10". I had them in .7 each with fill, and they played extremely well and relatively flat to ~25Hz under the seat in the F150.
#175
06-22-2010, 09:44 AM
I eagerly await your review of the Dayton and comparison to the BM (with more power on it, of course). As soon as I get some extra cash I will be getting the HO 10 and building a .7 cu ft box tuned to 30Hz for underseat use in the F150, and probably putting it in my dad's 08 F150. I am just incredibly curious as to how well it will perform as a single 10 in the F150, and honestly I have a good feeling about it. This may be on hold for a while though, next step is still the MS8.
WinISD calls for ~1.3 cubes for each Adire Koda 10". I had them in .7 each with fill, and they played extremely well and relatively flat to ~25Hz under the seat in the F150.
WinISD calls for ~1.3 cubes for each Adire Koda 10". I had them in .7 each with fill, and they played extremely well and relatively flat to ~25Hz under the seat in the F150.
#177
06-27-2010, 02:46 PM
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Pre-fab boxes for slim 12s are not made, and none that will fit the BM. You will need to build your own box or have one built.
As far as the results with the BMs: I've had mine in for a few months now, and I still believe they are easily the best possible subwoofer that can fit under the rear seat without a lift, both in output and clarity.
As far as the results with the BMs: I've had mine in for a few months now, and I still believe they are easily the best possible subwoofer that can fit under the rear seat without a lift, both in output and clarity.
#178
06-27-2010, 02:47 PM
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#179
06-27-2010, 04:55 PM
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You were also the one who said there wasn't enough excursion room for the BMs with that box. Regardless, I'm glad you could make it work.
#180
06-27-2010, 08:39 PM
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