[STL D]

After hearing my ultimax 18, a buddy of mine built himself one using the PE 4CuFt sealed box, same as mine.

Anyway, when driving it to med-high levels, 25hz and lower it makes an odd sound. Not the clanking noise that the bad round of 15"s suffered, it's more of a rubber slapping coming from the driver. It may be there at higher frequencies, but those frequencies have much higher noise factors, which make it so he can't hear it if it is there. We have triple checked for air leaked, and also made sure the surround is properly glued onto the driver.

I've never noticed if it is there on mine, but of course, I can't really crank mine as I live in a condo.

Any ideas on what may be causing it? The amp isn't clipping (it was at -12 on a iNuke 3000dsp), and his AVR has the sub out at -10, so that isn't the cause either.

 

[Samps]

Wire hitting back of cone or something else inside box? No dust cap to come loose, so that's out.

 

[STL D]

Wire hitting back of cone or something else inside box? No dust cap to come loose, so that's out.

I have a feeling that may be the case. Going to help him take the sub out of the box this weekend and try hooking it up in free air and see if it makes the same noise.

 

[dtsdig]

I purchased 2 10" Ultimax's recently and had similar issues with both. I believe the tabs that the binding posts are bolted to that connect to the voice coil wires are your culprit. Dayton doesn't seem to be very consistent on what direction those tabs are bent in. When the cone really gets moving, those tabs hit the bottom of the cone. You can either bend them down towards the spider or bend them straight up so they point at the underside of the surround. Bend them gently!
Here's what I'm talking about:

 

[STL D]

I purchased 2 10" Ultimax's recently and had similar issues with both. I believe the tabs that the binding posts are bolted to that connect to the voice coil wires are your culprit. Dayton doesn't seem to be very consistent on what direction those tabs are bent in. When the cone really gets moving, those tabs hit the bottom of the cone. You can either bend them down towards the spider or bend them straight up so they point at the underside of the surround. Bend them gently!
Here's what I'm talking about:

Thanks man. I'll be checking his out this weekend and I'll see if that's the case when I try running it free air.

When you did that, did the noise stop?

 

[Erich H]

One of my friends built a subwoofer with the 10" Ultimax and said he heard some funky noises that I didn't think he should be hearing at the volume he was playing. I wonder if those tabs were causing issues.

Thanks for the information, I'll check that out this weekend.

 

[BassThatHz]

The 10's must be different because the 15's have a lot of clearance there. I'm not even sure it would be possible.

 

[STL D]

I'm getting ready to head over there and take a look. I'll post what the culprit was as soon as I get back. Was suppose to do it yesterday, but my sitter backed out on me, and I'm not bringing a baby with me for a job like this.

 

[STL D]

Running in free air everything is fine, so it appears to be the cabling slapping the cone.

 

[STL D]

Redid the cabling and everything seems fine now. It was either hitting the rubber guard on the magnets, or the cone.

 

[timc1475]

This may not be applicable to your specific issue that appears you may have solved, but I will share in case you come across this in the future because if you don't know this it will drive you nuts.

For months I was sporadically hearing a dull thumping noise kinda like a low burble from a muffler's tailpipe from my 15" 1000 watt sub. I called the manufacturer and no one could help thinking I'd just have to live with it and consider it was just going out and time to replace it soon at another great cost...

The solution was odd. Turns out that since I have my computer near this sub the gateway (router / modem) was back feeding into the sub causing this noticeable burble all along! I raised the comcast gateway (a Docsis 3.0 Arris) up by only 2 feet away from the sub and the noise permanently stopped. I felt a sudden sense of self empowerment after being humbled by this dirty dog!

Nobody tells you these type of things that can cause major stress... you just have to either go through it or someone who has before shares. Anyway I hope the effort of my taking the time to type this with my 2 index fingers helps another at some point so they can overcome their own dirty dog.

Peace

 

[STL D]

Looks like I may have spoken too soon. The noise is still occurring, he just didn't hear it over what he was listening to.

I went over there and pushed down on the cone, and you can actually feel a tiny amount of air coming from somewhere on the driver itself. Possibly from the rubber surround.This explains why we didn't hear it in free air, because the leak doesn't have any pressure pushing through it until it is in a sealed box.

Looks like unfortunately he is going to have to file for an RMA.

 

[More is Better]

Looks like I may have spoken too soon. The noise is still occurring, he just didn't hear it over what he was listening to.

I went over there and pushed down on the cone, and you can actually feel a tiny amount of air coming from somewhere on the driver itself. Possibly from the rubber surround.This explains why we didn't hear it in free air, because the leak doesn't have any pressure pushing through it until it is in a sealed box.

Looks like unfortunately he is going to have to file for an RMA.

Or just put a dab of glue on the surround and glue it down to the basket.

 

[STL D]

Or just put a dab of glue on the surround and glue it down to the basket.

It's not coming from the outside of the surround, but from the cone side.

 

[Augerhandle]

It's not coming from the outside of the surround, but from the cone side.

Pictures?

 

[STL D]

Pictures?

I will ask him to take some, but there's really nothing to see. You cannot even tell by looking at it. It's only when you push down the cone that you feel a tiny breeze of air. I didn't even notice it til I put my ear to the cone and pushed in, and suddenly had air blow into my eye.

 

[STL D]

Here's a video show-casing the noise.

And no, that isn't the amp clipping. That was at only 375 watts. The second the cone gets moving in a box, that noise makes itself known.

In free air, it doesn't happen. Pushing down on the cone doesn't give any noises at all, but you can feel the air. The entire box has been leak tested as well. All EQ'ing has been disabled on the iNuke, the AV sub out was set all the way to -12 for this test run. It's definitely not a case of clipping causing this. Plus, if it was, it would occur in free air as well. The Screws are held in using t-nuts, which are very well sealed all the way around, and he has 3/4" wide 5/16" foam weather seal lining the entirety of the hole for the driver. The leak is definitely not due to the mount.

@DaytonAudioRory

Any ideas on anything else that could be causing this besides a possible air-leak in the driver itself? It has never seen above 700 watts, as he baby's his stuff until after break-in.

 

[STL D]

Matt over at parts express agreed that it seems like this driver is the issue, they're going to RMA it for him. Definitely impressed with their service, they had him a return shipping label within a half hour of seeing that video.

 

[brasspile]

Matt over at parts express agreed that it seems like this driver is the issue, they're going to RMA it for him. Definitely impressed with their service, they had him a return shipping label within a half hour of seeing that video.

More companies should have customer service like PE!!

 

[STL D]

More companies should have customer service like PE!!

Exactly. Plenty of companies make great products, but what makes a company shine is how they handle the situation when a bad one makes it out the door. It happens, doesn't matter how good your QC is, it's the nature of electronic components, there's a failure rate.

Most places make you pay your own return shipping, so this was impressive in my eyes.