3 12" Kenwoods. How Big of a box?

[tommymilan311]

Clearly you want as big as possible. I posted a few days back and got some helpful info. I've done some math and came to the conclusion that I can't fit as big of a box as I'd like. So now I'm onto the next thing.

How Big of a box do I need?

2 CUFT per chamber didn't work, and IDK if the math is different if I want to put 3 into 1 chamber. Is that math going to be the same? So try to fit 3 into 6 CUFT? I haven't done that math because I'm unsure how to go about it.

I have about 38" wide to work with, and 18" deep to work with, She'd also like to see out the back window, that gives us up to 24" I think, but that is a small window.

If I can't fit 6 CUFT, how much of a difference will 5 CUFT make?

She also very much likes the way here sealed box sounds, hits the lows. We have a ported box (assuming it is tuned to 35Hz or higher because it does not hit the lows like the sealed box) and she doesn't like the way it hits. So what tuning should I shoot for? 28Hz? 30Hz? Lower? I'm not sure here.

She is working with 3 Kenwood KFC-W3009.

Thanks for all and any help.

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[tommymilan311]

Also, what area will the vent need to be? I was shooting for roughly 35in^2 per chamber

 

[basswiigee2fix]

1.5 ported per sub 1.25 sealed... per sub recommended

 

[tommymilan311]

1.5 ported per sub 1.25 sealed... per sub recommended

She really likes her "deep bass" So I was going on the 2.0 CUFT per sub from the user manual for "deep bass". Could I achieve that "deep bass" from a smaller box? and what tuning?

To be perfectly honest this is also a test. I want to see how much of a difference in SPL it really makes having a ported box over a sealed, but I want to achieve the same level of "deepness" I'm getting form the sealed. She really likes that. Do I just tune the box lower?

Kinda looking for the best of both worlds.

EDIT:

How large should the port area be if I have all 3 in 1 box? Should I shoot for 90 IN^2 instead of the 30-40IN^2 that was recommended from the tutorial for WinISD and the math behind the box?

 

[basswiigee2fix]

She really likes her "deep bass" So I was going on the 2.0 CUFT per sub from the user manual for "deep bass". Could I achieve that "deep bass" from a smaller box? and what tuning?
To be perfectly honest this is also a test. I want to see how much of a difference in SPL it really makes having a ported box over a sealed, but I want to achieve the same level of "deepness" I'm getting form the sealed. She really likes that. Do I just tune the box lower?

Kinda looking for the best of both worlds.

EDIT:

How large should the port area be if I have all 3 in 1 box? Should I shoot for 90 IN^2 instead of the 30-40IN^2 that was recommended from the tutorial for WinISD and the math behind the box?

bigger box doesnt equal deeper bass... sometimes youll end up with a sloppy bass... a ported box to spec of 4.5cuft would probably be ur best bet...

tuning i wouldnt go under 32hz with those subs...

 

[tommymilan311]

bigger box doesnt equal deeper bass... sometimes youll end up with a sloppy bass... a ported box to spec of 4.5cuft would probably be ur best bet...

Alright, that sounds good to me, what about tuning? does tuning the box lower give a deeper bass, or should I tune to the recommended 32 Hz?

 

[basswiigee2fix]

play with torres box builder .....

 

[ThatChevyGuy 5,000+ posts]

youll most likely lose output with those subs tuned below 32, they dont have the motor strength, same goes for a bigger box, prob dont have the suspension for it. Id go with what wiigee said. Those subs are just horrid.

What are you using for power?

 

[Dmac1991]

Kenwood KFC subs HATE ported boxes. Well efficient ported boxes that is. I actually prefer them sealed compared to ported. I had two 12s in 4 cubes net ported (one of my first starter systems) on a 500w Kenwood KAC 9105d and they bottomed out ALOT on bass heavy songs. Switched to a 2 cube sealed box and they sounded alot better.

I'm sure a small ported box will be fine if output is what you desire with somewhat of a decent low end. I would do like 1.25 ported each. 3.75 ported tuned to 36

 

[tommymilan311]

youll most likely lose output with those subs tuned below 32, they dont have the motor strength, same goes for a bigger box, prob dont have the suspension for it. Id go with what wiigee said. Those subs are just horrid.
What are you using for power?

I'm at about 400 apiece

As far as them being horrid... That is subjective. She has heard my Alpines. They are every bit as loud but clarity isn't her thing. She likes her bass to sound low, lower than how I feel is intended. I think the last car had a deeper bass feed? All bass sounded much lower in her last car. We are just using converters and unplugging the factory sub and using that feed the components for the amp. This system sounds like it has a much cleaner more realistic sounding bass, she doesn't like it as much, I think it sounds good.

As for the Subs, they are pretty good for getting 4, and an amp, for less than 200. They are very very loud as well for 400 watts. For the most part, the Kenwoods give her exactly what she wants, brain rattling low bass.

 

[tommymilan311]

Kenwood KFC subs HATE ported boxes. Well efficient ported boxes that is. I actually prefer them sealed compared to ported. I had two 12s in 4 cubes net ported (one of my first starter systems) on a 500w Kenwood KAC 9105d and they bottomed out ALOT on bass heavy songs. Switched to a 2 cube sealed box and they sounded alot better.
I'm sure a small ported box will be fine if output is what you desire with somewhat of a decent low end. I would do like 1.25 ported each. 3.75 ported tuned to 36

She has a pair in a sealed box about that size. She also has a pair on a pirted box a little bigger. They are louder but not as "low" or bassy. Should i go with 3 sealed? Itd be easier. She wasnt disappointed with the sealed box.

 

[tommymilan311]

Ef it, should I just fit 4 in 1 sealed box? I got 'em, I'll need a amp though. This amp doesn't do so good with 1 ohm. It'll play for about 30, cut off for a couple seconds, and play for another 30. V-drop is perfectly fine, never went below 13V in the last car once the second battery was introduced. Now she has a beefed up ALT so I assume Vs will be less of a problem. Heat is no issue, amp has a fan built in, plus we have some fans to circulate air. I just think the amp can't handle 1 ohm. Oh well, I got it for around 50-80 (2 speakers, box, and amp for $120). So if it fries its no biggy.

Edit: WinISD data

Yellow = 4 Subs, Sealed Box, 1600 W, 4.00CUFT

Red = 3 Subs, Ported Box, 1200W, 3.75CUFT, 36Hz Port = 2, 16.5X4X66.19(not sure if this is total between the 2 ports?)

Cyan = 4 Subs, Ported Box, 1600W, 5.00CUFT, 36Hz Port = 2 16.5X4X47.96

What one?

 

[tommymilan311]

Okay, so when doing some more math. I came to the point that 300W/Speaker will give me maximum cone excursion, which is what I want, right?

Maximum cone excursion = highest output.

Bottoming out is when I'm going past the cone excursion correct?

Making SPL no different from 400W to 300W, correct?

So I have the new chart below, as well as cone excursion.

Yellow = 4 Subs, Sealed Box, 1200 W, 4.00CUFT

Red = 3 Subs, Ported Box, 1000W, 3.75CUFT, 36Hz Port = 2, 16.5X4X66.19(not sure if this is total between the 2 ports?)

Cyan = 4 Subs, Ported Box, 1200W, 5.00CUFT, 36Hz Port = 2 16.5X4X47.96

Also, how accurate is WinISD? Should I take these measurements to heart? or with a grain of salt?

 

[ThatChevyGuy 5,000+ posts]

Okay, so when doing some more math. I came to the point that 300W/Speaker will give me maximum cone excursion, which is what I want, right? Maximum cone excursion = highest output.

Bottoming out is when I'm going past the cone excursion correct?

Making SPL no different from 400W to 300W, correct?

So I have the new chart below, as well as cone excursion.

Yellow = 4 Subs, Sealed Box, 1200 W, 4.00CUFT

Red = 3 Subs, Ported Box, 1000W, 3.75CUFT, 36Hz Port = 2, 16.5X4X66.19(not sure if this is total between the 2 ports?)

Cyan = 4 Subs, Ported Box, 1200W, 5.00CUFT, 36Hz Port = 2 16.5X4X47.96

Also, how accurate is WinISD? Should I take these measurements to heart? or with a grain of salt?

Id put them all in sealed, those subs really do suck, ive used them also. They would bottom out and make mechanical noise with 600w to a pair sealed.

 

[tommymilan311]

Id put them all in sealed, those subs really do ****, ive used them.

All 4 in a sealed? I think I can get that to fit well in the space too, but I'd have to do something like 3 facing forward and 1 facing up, or 2 forward facing and 2 up.

What would be the better way to go?

1CUFT/Sub?

Also, those subs really do: Bang or ****?