Use of heat spreaders in sealed sub stuffing

[Beggar]

Hi

Im making slow progress with my electronically equalised sealed sub, trying to get things on the whole right, and im interested to know what people's opinions are on using copper piping etc, to distribute the hotness (generated by the kinetic to thermal energy change and from the cones themselves) from behind the sub cone(s) to the rest of the enclosure

I guess i have a few other questions as well,
- Is there a large temperature difference between the area around the cone and the rest of the enclose (im guessing yes)
- How much does it shorten cones life expectancy to have a [sarc]nice[/sarc] fiberglass etc, insulating layer around them
- How much does, and indeed how does temperature increase affect the characteristics of the enclosure, (i.e. should i think about heat sinking as well as spreading?)

Thanks for any help anyone can provide

 

[roddyama]

The typical direct radiating driver is about 1% efficient. This means that if you apply 100W of amplifier power, you’ll get 1 acoustic Watt from the front of the speaker radiating into the listening space. We can then assume that there is 1aW radiating in to the box from the rear of the speaker. This will not generate very much heat in the box.

If I had to guess (and it would be a guess) there is and order of magnitude more heat dissipated in the voicecoil/magnet structure.

 

[mrfeedback]

This Is Not A Problem.....

For domestic usage (power level, duty cycle and level) a woofer will not disipate significant heat into an enclosure and is not worth bothering about in the slightest.
If such an enclosure is ported, air will circulate and equalise inside/outside temperatures anyway.

That said, I have put my hand inside a 100 Hz and up PA cabinet that had just done a long loud show, and the magnet assembly was surprisingly seriously hot - hot enough for me to take note, and hot enough to not want to keep my hand in contact.
The interior of this cabinet was warm to the feel also.
I also end up repairing PA passive crossover networks that have been literally toasted, but these instances are seriously high power applications and far remote from domestic situations.
If you were to duplicate PA levels your neighbours will be around.

Eric.

 

[Beggar]

Thanks for your replies!

These ones in particluar seem to have made my life a lot easier, now to start planning that water cooled amp.....