unloading

loudwagon15s · Post by **loudwagon15s** » Fri Jan 16, 2009 1:32 pm

ok, i could use your guy's help, i blew another sub and i have no doubt that it was because of the sub unloading on the port because the coil is completely smashed on one side (box was 1.5 tuned to 38 for 1 sqx 10") i know wayy too big, but its what i had (song: lil jon let's go)
so, can someone elaborate on the sub unloading, what it is, how to avoid it

thanks, Chris

Ryan from Ohio · Post by **Ryan from Ohio** » Fri Jan 16, 2009 1:42 pm

Playing below your F3 point.

Get a subsonic filter!

Bwcad1 · Post by **Bwcad1** » Fri Jan 16, 2009 1:52 pm

Unloading is the mechanical suspension reaching a point of no longer maintaining linearity. Over power for the enclosure volume is usually the culprit. Unloading or side loading can also occur if the back of the box has 2 different heights and one side of the cone is closer to the back of the enclosure than the other. this can cause increased pressure on that side of the cone loading the sub sideways causing coil rub's. it sounds to me like you have both.

Tim · Post by **Tim** » Fri Jan 16, 2009 2:25 pm

Bwcad1 wrote:Unloading is the mechanical suspension reaching a point of no longer maintaining linearity. Over power for the enclosure volume is usually the culprit. Unloading or side loading can also occur if the back of the box has 2 different heights and one side of the cone is closer to the back of the enclosure than the other. this can cause increased pressure on that side of the cone loading the sub sideways causing coil rub's. it sounds to me like you have both.

Okay that being said, and forgive the question, but what can be done to prevent it from happening. Is it as simple as making sure all sides of the enclosure are equal??

Tim

Bwcad1 · Post by **Bwcad1** » Fri Jan 16, 2009 2:54 pm

Making sure the cone is on a symmetrical surface. Make sure your enclosure volume reacts well with your power. to much volume and to much power will cause unloading as well.

Tim · Post by **Tim** » Fri Jan 16, 2009 3:07 pm

Okay got that much. Is there a general rule to go by??

Tim

loudwagon15s · Post by **loudwagon15s** » Fri Jan 16, 2009 3:32 pm

Ryan from Ohio wrote:Playing below your F3 point.
Get a subsonic filter!

got one, it was set at about 33-35 hz, which is why i was really scratching my head when it blew

Bwcad1 · Post by **Bwcad1** » Fri Jan 16, 2009 3:33 pm

Not really. Unloading isnt a frequent thing getting it right in extremely infrequent. what i usually build a basic assessment on is the larger the box the less power it needs. so you can start from the manufacturer specs and work from there. 500rms and 1.25cuft so lets 2.5 cf and 250 rms, analyze the results and make adjustments according. This is y i get upset when someone calls themselves an enclosure designer. 90per dont know anything about enclosure's or get into the science and physics involved they can draw a square box guess at the port size and tell you how to make a wooden box. thats not to say i dont get one wrong every once in a while lol

swimmerdude · Post by **swimmerdude** » Fri Jan 16, 2009 4:23 pm

holy s*** chris!!!! are you trying to fill in my foot steps?? I used to blow my equipment up, not you. lol. and bill gave you the low down. too big of box, gained efficiency so with enough power, by by sub.

neumann · Post by **neumann** » Fri Jan 16, 2009 5:16 pm

my record is still clean