Sealed 2.5 cubes for 15" D2 work for SQ aetup?

[alann 0]

I just bought a 15" D2 and wants to know if 2.5 cubes sealed box would be a good size for the sub, this is strictly for SQ.

Thanks!

Edited August 27, 2006 by alann

[Tirefryr 1,742]

Yes, you will be good with that.

[Electrodynamic 2]

^ What Tirefryr said. That'll be just fine.

[PaulD 0]

I know the obvious answer ...... but what about if the box were a little bigger (same speaker) ? I want to have output at low freq's

[Tirefryr 1,742]

It will increase the efficiency and lowend extension. Increasing the size will also drop the powerhandling. The airspring on the cone if less with a larger enclosure and it's easier to overdrive the woofer. Now, don't get scared by this as a small increase in volume will not be detrimental at all. You can always build a little larger and if it's not what you like, simply add something to the interior to take up some space effectively dropping the internal volume.

[CBFryman 2]

Ryan, paul knows what he is doing.

Paul, I had mine in 2.6 with some batting in the back and it was excelent. Some of the best earsex I've had in a vehicle basswise. Though I never measured it, it sounded as flat as a board.

[Tirefryr 1,742]

Hey, he asked, so I answered. I don't know what he knows. Just tried to answer the best I could. This also provides info for future use if others have the same question.

[PaulD 0]

ok, cool ...... my expertise is more in the SQ realm. Maybe I should model this in that winisd program, too bad it doesn't really take the car volume/shape into effect. My goal is to have strong bass down to 20 Hz or so

[Tirefryr 1,742]

WinISD will be of no help. It does not accurately graph the Mag, nor does Bassbox for that matter. All you are going to see in a correct model is a flatteniing curve on the low end and a slighty lower F3.

[Electrodynamic 2]

WinISD should be used for port calculation alone, and nothing more. As much as it helps, it hurts. Take a Mag 12 at 2 cubes tuned to 34 Hz - doesn't look the best does it? Now listen to Loyd's car with that alignment and you'll never use WinISD the same. Loyd's car drops LOW, gets LOUD, and sounds great.

Without getting carried away, don't use WinISD for response graphs and/or enclosure calculations. We've done our homework and what we recommend works out well in all vehicles. Getting more vehicle specific can change the enclosure volumes and tuning, but that requires a LOT of testing and a lot of expense.

[PaulD 0]

I guess this is why most of the SQ based fiberglassed boxes are sealed, they don't want to rebuild them every weekend. I guess my problem with tuning to 34 Hz (ported enclosure) is that the sub will be unloaded below like 30 Hz ...... that won't kill it without a fairly steep sub bass filter ?

[Tirefryr 1,742]

You'll be fine.

[Electrodynamic 2]

Nope, it won't kill it. It'll be just fine.

Loyd's car, BTW, has an F3 of 22 Hz or so. Low end will be plentiful.

BTW: Tuning to 32 or 30 Hz is fine as well. Going below 30 is what usually causes problems in larger vehicles, which is why we don't recommend it for car audio.

[CBFryman 2]

I'm tuned to 34Hz right now and I dont have a problem with low end. On the other hand I have 2 15's...

[kappa546 0]

I'm tuned to 34Hz right now and I dont have a problem with low end. On the other hand I have 2 15's...

i ran my 15" in 3 cubes sealed and it was fantastic. smooth, tight and hit so low.