cooling using BR airflow?

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I am working on a supertweeter arrangement to be fitted in my speaker, that tends to run quite hot (plasma DIY.. ouch). Now, would it be a stupid idea to use the bass reflex airflow to cool internal heatsinks, or will I risk anything on doing so...? The driver pumping air is by the way an WR125S and runs quite high (fullrange).. Volume is quite small.. 7 liter.. I'm not going to fry the voicecoil by overheating the box, will I?
 
I wouldn't do it unless I did experiments to verify that there is any significant transfer of heat through the port airflow, using the particular driver and box size that you are using. I don't know of any professional application that does this. At typical volumes there is little air motion of the port - especially with a small driver - and I doubt there would be much of a heat transfer effect.
 
Try this:

Take a single sheet of toilet paper or tissue paper and put it in front of your port and see what happens (ha ha, no jokes please).

I just tried this on my small computer speakers. Even with the volume cranked, the tissue hardly moved. In fact, it tended to suck into the port more than anything, so I think I have an air leak somewhere, but I just don't see how it would cool anything.

Great idea though.

Doug
 
Take a peice of tissue, put it over the port, and see what happens!

Are we talking about subwoofers here or what? I can feel the air movement from the port a few feet away with a 10hz sine 10hz tuning and an adire tumult in a 6 cubic foot enclosure. Put a tissue over the port and it will be RIPPED AND SCATTERED
 
BassAwdyO: No subwoofers here. 4.5'' driver... But it does in fact have pretty powerful (if it's any help with that sized driver)

Taperwood:
I tried your toilet paper ;) The little thing does actually push some air, much more than you would expect it to (wich is next to nothing, right?). I have no way of determining how much, in real life, so I took a WinISD test. Mostly I'll be using around 4W I guess (ineficcient driver, 4W gives about 92dB/m) and with that WinISD calculates an airflow of 3,319m/s at 100Hz rising pretty linear to the maximum point at 50Hz with 8.711m/s. max volume displacement occurs at 50Hz with 4W, a +/-6mm exercution providing 34cu.cm volume displacement..

Also, I'll be less likely to use the supertweeter at low listening levels..

What if I build a new vent using a square crossection (im using a round plastic one now) but of aluminium, with heatsinks forming sort of vertical "shark teeth" that'll filter the air flow?

I'd had to rebuild the box for this, but hey they look like **** anyways..

Edit: Heck, I'll make a test with a heatsink and a power resistor (I have a mountable 22Kohm 50W that I can use). That'll give an indication at least...
 
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