[Nazo]

Ok, I have a pair of HD280 Pros that have been modified with a Bluetak mod (and further I've put capacitors in them to act as simple first order high-pass filters to reduce that ugly bass hump to a slightly more reasonable level.) Rather than Bluetak since I couldn't find it, I'm using "Loctite" brand which as far as I can determine is basically the exact same stuff (they even felt the need to color it blue, though I suspect the color has absolutely no real meaning whatsoever and is probably just a dye or something added to it.) Now I've read that inside a car it can get up to as much as 140F (or 60C) though I don't really have any thermometers to test. Certainly temperatures in my area have been absolutely ridiculous lately actually going over 100F at times, so I am definitely able to believe that in the confined environment of a car with all of those windows it could get that hot (though I do put a couple of things in the front windshield that block a lot of the light through it -- I couldn't find a well-fitting reflective protector though.) It worries me that it might technically be possible for it to go even higher inside the car. The headphones themselves aren't just sitting right out in plain sight though (well, that would just be stupid. People have been known to break into cars for less, regardless of any concerns about temperatures or anything else.) I used to keep them under a coat, but recently I've found a nice little box. It's a thin metal on the outside with I think cardboard on the middle and the entire inside is lined with a thin but dense foam material. I stick this box under the coat, so in essence the headphones get the benefits of two insulative materials between them and the air of the car itself (plus absolutely no direct exposure to the actual UV rays.) Still, I was worried and opened it up to test them out (still working fine so far) and it was definitely quite hot inside the box. On the up side, all of that insulation has the advantage of ensuring that actual temperature changes should be pretty slow rather than being at all sudden (and sudden fast temperature changes are the most deadly to electronics by all that I've ever heard -- more so than high temperatures themselves is the sudden change either to or from them usually.)

The capacitors say 80C on them, so I'm not terribly worried about them. It's higher than ideal, but still a pretty wide range below their maximum (plus they aren't actually active during these most extreme temperatures anyway. If I'm listening I'm inside a nice, well cooled building at the time... No way am I putting those already headphones on inside the car without at a minimum the windows wide open and wind flowing through.) I can't find any info on the safe storage temperatures of the Loctite putty, but it does say "will not dry out" (so I guess it's oil based rather than water based anyway.) What I'm really worried about are the drivers themselves though. Besides glues and such, they use plastics and such that might not have been designed for these sorts of temperatures. Certainly Sennheiser officially says "do not expose to extreme temperatures" in their little maintenance flash page, but that doesn't really say anything at all. I can't find any sort of official stand on temperature ranges in the texts available for download and I've long since lost the manual. "Extreme" could mean "don't point a flame at them" for all I know... (And in normal low temperatures I suspect condensation or freezing of moisture in the air is the real danger rather than the temperature itself. I just can't imagine the components being harmed by normal low temperatures. Again, the insulation around them probably would be ok, but, to be honest it's quite rare that we experience extremely cold temperatures in my area anyway. Now, if you poured liquid nitrogen on them or something, THAT could damage them, but I definitely wouldn't call that a normal temperature.)

Is there any sort of official statement on the true safe storage temperature range of these headphones? Has anyone maybe experienced a meltdown or anything due to storing them in any way remotely like this? (I know I'm kind of the odd one out here -- few would normally keep headphones like these in a car, but that's where I need them to be.) I don't care a lot about the HD280 Pros -- they are quite possibly my least favorite of all of the real headphones I've ever used. I just like them because they have an excellent seal, were relatively cheap, and at least good enough to still enjoy my music. I keep them in the car because I only use them away from home in public where I don't want to share my music with everyone nearby and have absolutely no use for them at home where I have the modified HD555s I love so much more. I'm not going to lose any sleep over it if they suddenly die, but I do still need something and I'm sick of IEMs (even as much more comfortable and generally better than earbuds as they are, they just aren't headphones.) So I'd rather at least make a decent effort to keep them from tearing up. It just defeats the purpose if that effort means not keeping them in there where I really need them to be (if I kept them at home and just put them in there when I knew I'd need them, I wouldn't have them many times when I did need them but didn't know in advance and I'd forget to put them in many times when I would have known but just didn't think about it or I'd simply forget.)