Ok so I made a few boxes for my hdc4 and it sounded good except on a particular note. I believe it was a higher frequency seeing as how I still hit the lows and moved air fine. If you listen to "candy shop by 50 cent. It's that bass note through out the song. My sub makes noises like a knocking noise. I can hear in the port and I can hear it when I listen to the sub.

Any ways I thought it was the tuning so I made quite a few boxes but had same results or less noticeable, but still there results. I'd listen to it free air and it sounded fine. I even switched the subs to a different brand and it didn't make that noise. So I was assuming it was the speaker. But then I tried it with the candy shop song because when I tried it free air I kept forgetting what songs it did it on and sure enough, I had the sub on my arm rest/center console, and it made the noise! I was like wtf. But as I tilted the sub it went away slightly, so I layed it down, so there was no obstruction to the air coming out the motor. And it was fine! I put my hand over the hole and it made the noise. So I'm thinking my sub is mounted too close to the back wall. My box is 15" deep gross, and I have my sub forward firing, so the distance between the wall and sub is like 5.75" I emailed soundqubed and they said needs to be a minimum of 6" away, so I'm gonna double baffle it witch will put me at 6.5" away. Do you think that will make a difference?

Is this the kind of effect being too close to a wall have? Now that I think about it, I haven't really build a box this skinny lol. Maybe the same height but depth would he like 2 ft. Lol. Hope to hear some inputs from you guys.

I have seen that happen before...

 

just for kicks make shure your access wire in the enclosure is not curled up and hitting the back of the cone

I know it sounds weird....sometimes it will make a funny noise when the cone sucks in on certain frequencies

 

if your just compressing with the cone in a confined space it can sometimes have weird effects to

I try and have the cone diameter distance away from any wall...if I can't I found a way to combat it,

...I try and take advantage of the corner of the enclosure and wedge it , giving the sub more space to unload

What do you mean aboutyou wedging the corner?

Edited February 15, 201510 yr by ManzKea

this one is wedged

 

my wife can stuff the hatch full of boxes from costco and the sub can still unload

 

Edited February 15, 201510 yr by Thumpper

That's a sweet box man! Lol I wouldn't know where to begin to make a box like that. Btw howd you get the screws in ? Looks kinda tight to fit a drill for the back screws

So I put that baffle thing for the front and it didn't work. So I covered the front hole caulked it and made a new hole up top. And .....it still does it. This sub is starting to get on my nerves lol. Mounted on the top it has just over 11" of distance between the magnet and the bottom of the box.

My box is 48.5" L x 20"H x 15" D tuned to 33hz with a 5x18.5" port.

on a ghost hunt......

 

try turning the x-over down a few hz and see if it makes a difference

I have it on 50hz. The lowest setting =/

Same thing....tomorrow I will try the last possible thing I can think of. I'm gonna flip it. It should be the end all possible solution. If it still does it, idk what the heck.

this wasn't making sense to me anymore so I re read the first post

I kind of read it wrong  , I was thinking outside the box instead of inside...LOL

I have mounted vented subs close to the rear wall with out problems

 

it almost sounds like the aluminum former is tapping the pole piece or the magnet assembly

Lol. Idk man. This thing is getting on my nerves. How would I be able to tell? But like I said before, when I free aired it with no obstruction to the bottom vent it sounds normal. But as I put my hand near the vent, it has I guess the air it's it's pushing out bounces off my hand and goes back in the hole and I guess causes a conflict. Lol. Maybe I should shoot a video lol so we got better under standing

Lol. Idk man. This thing is getting on my nerves. How would I be able to tell? But like I said before, when I free aired it with no obstruction to the bottom vent it sounds normal. But as I put my hand near the vent, it has I guess the air it's it's pushing out bounces off my hand and goes back in the hole and I guess causes a conflict. Lol. Maybe I should shoot a video lol so we got better under standing

A video would be great

Hdc4 making some funky noise:

*inside the port. You can still hear the noise

Subs inverted

Hdc4 making some funky noise:

Subs normal

Hdc4 making some funky noise:

Lmk if the links work

check all the way around the dustcap and see if the glue come loose somewhere....

Ok will do thumpper. Thanks for the suggestion. Btw I just got this sub like a few weeks ago straight from their website

if the dust cap comes loose plugging the cooling vent hole it will flap make a clicking or clacking noise

 

free air the sub again and plug the hole...watch the dustcap

No everything looks glued and secured to me.

Man I should've went with some ssa's or something.

Man I should've went with some ssa's or something.

Speaker boy... Whats up? You got experience with em

I have never owned an SSA woofer, however in the several years since I joined SSA (I was a freshman in highschool, i'm 21 going on 22) I have yet to hear a bad review about their woofers. Have wanted an icon for about forever. In fact, was finally going to jump on one but I came across my FI for only 250 so I snagged it instead and some components.

strange....

 

the only other things I can think of ...maybe you bottomed the sub out and damaged the bottom of the former

over exertion can damage it too

 

 

or the cone assembly is glued in crooked and making contact the pole piece

 

 

I wish I could have a look at it....to bad it's only a 2,000 mile trip...LOL

Edited February 16, 201510 yr by Thumpper

You think it could be glued crooked if it came straight from the company?

when you held your hand over the cooling vent hole  and it started making that weird noise

the first thing that came to my mind was the dust cap was coming unglued somewhere

 letting air out from the preasure build up......it will make a clicking or clacking noise

 

 I would double check all the glued seems

 

  have only seen 2 woofers in my lifetime with a crooked cone job , it is possible

but highly unlikely though , they no doubt use centering tools

 

 

 

  did that woofer make that noise from new ????

Edited February 17, 201510 yr by Thumpper

Us I just noticed it. Because it only does it on quick kick drum bass notes. And I've only had it for less than a month. It hits all the low notes fine. But quick high notes it does it. It plays all the notes from white cloud fine.

I got a test tone generator and it plays all the notes from 24hz, to like 150. I had a preowned sundown zv3 in the same box and it didn't do that noise ever. Could it be because its a new sub and needs to break in?

Again free air with nothing obstructing the hole in the magnet it sounds normal no noise but as soon as I put it in the box there's a Damn noise.

I made two boxes. One at 4.5 tuned to 36 and it does that noise minimal in a few of the songs I know it does it on. But candy shop still sounds like ass.

I did another box at 5.08cuft tuned to 33hz and the candy shop song songs like complete ass. And so does a few of the songs