How damaging is heat to powered speakers?

[mikekars]

I had a very small pool party gig yesterday with  simple DJ music.  I used some Mackie SRM450 V2 powered speakers on sticks as the mains because that was all this event warranted.  Now these are not best sounding boxes in the world but I have six of  them for foldback monitors and  they have done OK  in that duty at my level.

The temperature was about 95 degrees and the backs of the speakers were facing west and in the direct sun all afternoon.  These are passively cooled, no fan.  The speakers are solid black including the cooling fins in the back.  Well the plastic  box itself was too hot to touch and the cooling fins were waaaay too hot to touch.  I am pretty sure this was mostly just from the sun beating on it as I have used these often outdoors with partial shade and they normally get pretty warm but not too hot to touch.

When I realized just how dang hot they were I was actually sort of impressed they were still pounding out the music without any noticeable problems.  But my question is whether this use  (abuse?) could greatly reduce the life of the speaker?  I mean the built in amp and electronics or the drivers themselves.  I could definitely take steps to shade them better if I am really accelerating the cumulative wear on the unit.  But if not then I don't need more stuff to worry about.

[agedhorse]

Direct sun on the heatsinks can cause damage under some circumstances, but in general, moderate heat (heat that is typical for a gig, not a solar collector) is not goinng to be an issue on well designed products.

[Pro Sound Guy]

Would not last long in Death Valley today @ 130F

[Pro Sound Guy]

Look at the bill of a baseball hat and come up with something that comes straight off the top of the back

of the loudspeaker that will shade the heat sinks and not impede airflow

[WynnD]

Just one more thought. These units usually live in 70 degree rooms indoors. Outdoors on a sunny day the temperature might get near 110. That's only 40 degrees hotter. It does affect cooling some, but CPUs are usually safe to an internal temp of 140 degrees. I would think that power transistors would be similar and I'm guessing that a 30 degree minimum difference is probably about what the designers are calculating in. Andy probably has been through these discussions during a design session. (And probably can't talk about it for legal reasons. But I'm just guessing.) Got to admit that my PVR computer gets marginal on a hot day when the room temperature reaches 90 and I'm trying to play one of the GPU intensive games. GPU temps reach 95 Celsius and I have three exhaust fans pulling fresh air across the GPU and out of the case. (As well as a fan on the GPU heat sink itself. I need to look into a larger and better heat sink. Liquid cooling maybe.)