slapping sound?

[tezin87 0]

My 10'' bl came in today and I couldn't wait to hear how my box turned out. Here's a picture of what it looks like:

The box is roughly 1.15@33hz with a 3'' aeroport. But when the lower bass notes (in rap) were played, there was a very distinct "slapping" noise coming from inside the port to the beat of the bass. Is this considered port noise? Or could it be that one of the wires inside the enclosure is too long and is hitting the side of the box/sub? Or could it be a leak somewhere? It is very noticeable, especially because it is behind the seats in a reg cab pickup and the port is firing up right behind your head.

[audio-neon 34]

sounds like an air leak to me.

[tezin87 0]

If it is an airleak it is probably where I ran the wire through the box. I tried caulking around them but it was kind of a piss-poor job. The noise wasn't on the higher frequencies it was only on the lower notes where the air was really coming out of the port.

[Big E 4]

Play a song and feel around the port and around the ring of the sub when you have that noise. If you can feel air coming through, you need to put some sort of weatherstripping between them, or find some way to seal that off.

Edited June 18, 2008 by Big E

[tezin87 0]

My mounting hole is also a little tight because I didn't have a router or jasper jig. I just used a jig saw and left it a little small. When the sub came in today I used a dremel drill to make the hole just big enough for the bl to fit in. Maybe a little air is leaking underneath the mounting gasket or something.

[tezin87 0]

I must say I was very impressed with the bl though. It is built like a tank and is much heavier than I anticipated. I probably won't be able to resolve the noise issue until this weekend when I get the seats and carpet out of the truck and have some room to move around.

[Aaron Clinton 2,372]

I would suggest taking it easy on the driver until you resolve the problem because we are not sure what is happening just yet.

[tezin87 0]

I would suggest taking it easy on the driver until you resolve the problem because we are not sure what is happening just yet.

I only had it hooked up for about 30 min last night because it was my first build and I couldn't wait any longer to hear how it turned out. Not too well I guess But I took the amp out of the truck and it is back in the house with the other pieces waiting to be installed.

[tezin87 0]

has anyone else heard this "slapping noise" coming out of their port before?

[talon tsi 0]

...not sure if mine was the same sound as urs...air was being pushed out of my port into a raised area of my carpet that was open....thats wat mine was...

[tezin87 0]

I don't think that is what mine is. My port is firing up towards the ceiling, but its a good 3 ft. away. I'm thinking it is just port noise, but I don't know how I can be getting port noise from such a small enclosure with a 3'' aero. Maybe my port has a leak in it on the inside of the enclosure, can that cause port noise?

[KU40 173]

try playing the sub outside of the box

[audio-neon 34]

try playing the sub outside of the box

IF YOU TRY THIS:

-Keep the volume and gains low. A sub will move a lot more free air than it will in a box, therefore it is much more prone to mechanical failure.

-Keep the bottom of the motor off of something if it has a vent.

-Don't put it near other electrical devices such as a tv, it has a ton of magnet force and can permanently damage a TV.

-Keep the soft parts of the sub clear from any debris and make sure nothing gets on the former/voice coil. A good demonstration of free air playing can be found here:

It is one of my old set-ups. You can actually hear a noise in that video from the air getting trapped in the pole vent because the bottom of the sub wasn't clear. I also wired my subs up to 4 ohms for that video, and turned the gains down and as you can see they still moved quite a bit.

[tezin87 0]

Thanks for all the tips/advice guys. I'll try it out after work.

[tezin87 0]

I fooled around with the settings on the amp a little bit and I didn't notice the noise as much. Now I just hear some port noise. But I guess having a port that close to your head will make you hear it easier. I am very very impressed by the amount of bass coming out of that 10'' bl. Now I just need to figure out how to dial in that JL amp. This is a totally different subject but I tried setting the gain with a 50hz tone and I couldn't get the fluke meter to read a steady voltage. I followed the directions on JL's website and I couldn't get it right.

[tezin87 0]

So I messed around with my amp during my lunch break and played some songs pretty hard. The noise I'm hearing is most definitely chuffing coming from the port. I don't have a clue how I'm getting so much port noise. I might try and designing a new box with the port firing into a corner or something but this would bring the box down to 1ft@35 or so. Does anyone think this would reduce port noise?

[KU40 173]

only way to reduce port noise since you already have an aeroport is to increase port area.

[tezin87 0]

I don't have the room to add another one. I read that a 3'' aero would be enough port area for my box size though. Do you think the port noise can be from not sealing the 90 onto the tube well enough?

[KU40 173]

only if it's loose and has a little lip there. Basically anything that will cause turbulance in the port.