Mechanical limits

[1ndatrunk 10+ year member]

Can a sub take more power if it has not reached its mechanical limits. I have a Treo SSI 15 on roughly 1100 watts, with a good electrical system. Its excursion is nowhere near its full range. Its loud, but I think it has more, what do you guys think? Should I go say 1500 - 1700 watts? My enclosure in 4.3cuft tuned to 35hz.

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[wu501 10+ year member]

whats the sub rms/max ratings

 

[grimreper912003 5,000+ posts]

It may be at its thermal limits. Also how do you know if the the spiders are at there limit or not?

 

[Ed Lester 10+ year member]

most subs can take a bit more than what they advertise. This is not only for liability reasons, but also because the Manufacturer cant always tell what the consumer will be doing to the sub.

I say put up to 2000w and see how it goes. If you start to smell something funny, turn it down.

 

[Hintzyboy 5,000+ posts]

Sub isn't going to excurt as much in a ported enclosure unless you play below tuning (which will lead to bottoming out). In fact, the cone shouldn't move much at all at tuning. I wouldn't put much more than rated power to it. You will very likely hit thermal limits before mechanical limits

 

[audioholic 5,000+ posts]

Like Hintzboy said, cone excursion is greatly controlled by the enclosure/tuning in a vented setup. To say the sub isn't reaching its mechanical limits, in a ported box, makes me think you don't realize this.

Excursion also increases as the signal moves up from tuning. Alot of people will tell you excursion means nothing in ported boxes, or only factors in below tuning. Both of these statements are based on partial truth, but aren't quite accurate.

When burping for an SPL, the signal does not vary from tuning much, thus excursion is minimized and mechanical limits become a minor factor (except in extreme cases). That is where the idea that excursion is meaningless in ported systems comes from. but we dont burp at tuning when we play music, its transient, and cone excursion can become a factor.

As said before, a speaker basically has 2 limit thresholds... mechanical and thermal. Surpassing either one can lead to premature speaker failure. Just because your speaker, in its ported box, has more mechanical capabilities does not mean the speaker is not running to its full potential. In ported boxes, again due to decreased excursion at/near tuning, thermal limits tend to become the limiting factor, not mechanical. That's not always the case, as I stated above, but you need to at last consider thermal limits when deciding the sub has more potential to give you.

 

[pjvoc 10+ year member]

somone once told me that because I had such a big box, I was gonna make the subs reach their mechanical limits, wtf did that mean?

 

[Bun-Bun 10+ year member]

somone once told me that because I had such a big box, I was gonna make the subs reach their mechanical limits, wtf did that mean?

If the box is too big the subs can lose cone control... probably what they meant.

Or there just stupid and talking out there ***.

 

[pjvoc 10+ year member]

its 2 15" mmats juggernaut hybrids, and the box is 12 cubes @ 32 hz I doubt its too big, sounds fine to me //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

what does subs losing cone control involve?

 

[audioholic 5,000+ posts]

somone once told me that because I had such a big box, I was gonna make the subs reach their mechanical limits, wtf did that mean?

Think of the air in your box as an 'air spring'. As the cone tries to push in, it compresses the air molecules slightly. This compression force also as an equally opposite force on the cone, trying to force it back to its centered position, thereby equalizing air pressure inside and outside the box.
Now imagine two boxes, one being twice as big as the other. The bigger box has more air molecule to compress, yet the speaker's cone still displaces the same amount of air space (excursion x diameter), so each air molecule will be compressed less. Extrapolating that information you will realize then that the cone, in the twice as large box, could move its cone twice as far before it felt the same return force on the cone as it would in the box half the size. That is ignoring the speaker's suspension compliance of course.

Cliff notes: Bigger box = less resistance to cone excursion, so its easier to 'bottom out' sooner. Smaller box = more resistance to cone excursion, so its harder to get it to 'bottom out'.

 

[audioholic 5,000+ posts]

If the box is too big the subs can lose cone control... probably what they meant.
Or there just stupid and talking out there ***.

"Cone control" usually describes the speaker's ability to control cone 'over hang' as the cone changes direction. I think you will find while the enclosure does affect this, the speaker's suspension and BL force/curve will also play a major role.
In other words, a large box does not necessarily mean 'sloppy' bass as alot of people tend to think. If that were the case, all those SQ guys running infinite baffle are doing something drastically wrong. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[pjvoc 10+ year member]

yeah i have a huge box, but i still have a very nice amount of clean bass IMO

 

[audioholic 5,000+ posts]

No offense, but with Juggs? I dont think even mmats claims Juggs sound good do they? lol //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif

j/k sorta, Im sure they hit all the notes you ask them to, which is what counts.

 

[1ndatrunk 10+ year member]

My sub is inverted, well it was at one time, so thats how I know it hasn't reached its mechanical limit. Thanks for the info guys. The sub is rated 750rms 1500 max but its taking my amp and eating it. I guess I'll leave it alone and just get one more sub and amp. Anyone know where I can get a Treo SSI 15.22 from? Or another Lanzar 1800d?