Dayton classic 18 project

[Rob B]

I've built a simple 15ft ported enclosure loaded with a Dayton classic 18. Its made out of 23/32 b/c grade pine plywood, slot port tuned to 30hz. braced pretty minimally, but the box doesn't seem resonant. 15ft is the actual airspace. 100hz 2nd order passive crossover.

Anyways my problem is that around 70hz and up at any good amount of power the driver buzzes, it sounds very metallic as if the frame is resonating. I've never seen or heard anything like this before, Ive had chinsy boxes that resonate and i know what that sounds like and this is totally different. It sounds allot like a heat shield vibrating, (as in a car with a loose or damaged heat shield), very metallic.

Is it possible to have a frame that resonates at this low of a frequency? I know my box could use more bracing but the sound really seems to come directly from the driver.


I'll post pics as soon as i have some.

 

[m R g S r]

Is it the aluminum cone? Or the classic doesn't have an aluminum cone?

 

[Rob B]

no, the classic is the cheepie. paper cone, rubber surround, steel frame.

 

[m R g S r]

Stamped steel? Still with the gauge they use and the ribs pressed into the legs of the frame, I can't see it being flimsy enough to "ring"
Who knows. Is the spider connected / glued all around?

 

[Rob B]

Oh yea, i should have deffinitely mentioned that the spider came unglued the first time i hooked it up to my big amp. I glued it back in place with a 2 part epoxy i get from work (I'm a mechanic), I trust this glue.

but it made the same noise before the thing came unglued anyways, maybe something else is loose and ready to come unglued.

 

[m R g S r]

That's deff a mark against the quality of that driver I guess.

I have had no problems like that with my Dayton drivers

 

[Rob B]

Yea well, its the first dayton product I've purchased... I was a little upset when it went, it sounded like a jack hammer. It seems to play the same after I repaird it though.

what else could create a buzzing in woofer? I'm wondering if maybe the magnet or end plate is loose, maybe something simple like the wire terminals, something must be loose now that i think of it.

I should call dayton and chew someones *** out, see if they can send me a new woofer lol.

 

[Richard Ellis]

If you can get a hold of a sweep generator (Free online) run the sweep, lock onto the F and manipulate the enclosure to isolate the source. I've found enclosures both old & new that will resonate (Buzz) at a variety of frequencies.
Listening to a low frequency sweep is very revealing......run the sweep slowly though.
***just saw you isolated it to the driver, try a sweep anyway***
___________________________________________________________Rick.....

 

[Rob B]

I have test tones from 0-200hz in 10hz steps, that's how i usually isolate a concern. but this is such an obvious problem, I mean the mechanical noise is louder then the actual output of the woofer at certain frequencies.

 

[NEO Dan]

Take the driver out of the box and sweep at ~5 volts, if it is the driver making noise see about getting a replacement. Unfortunately you've modded the driver by repairing it, good luck getting it warrantied.