Leaving a cabinet in a car?

[4 Strings]

Your car interior is full of electronics far more complex and sensitive than a a bass cab, and materials more delicate than paper cones (it even includes paper cones in the car speakers). None of them suffer from being part of a car.

Unless your car leaks onto your cabinet or you leave the windows open there's no difference to it being anywhere else.

A shed would be different.

[xgsjx]

[quote name='4 Strings' post='1279269' date='Jun 23 2011, 12:30 AM']Your car interior is full of electronics far more complex and sensitive than a a bass cab, and materials more delicate than paper cones (it even includes paper cones in the car speakers). None of them suffer from being part of a car.

Unless your car leaks onto your cabinet or you leave the windows open there's no difference to it being anywhere else.

[b]A shed would be different.[/b][/quote]
Why would he want to stick a shed in his car?

[escholl]

[quote name='BasH' post='1273117' date='Jun 17 2011, 08:01 PM']Apparently this can already happen at room temperature. As long as the change in temperature is big enough (so these metallurgy lessons weren't in vain at University).[/quote]
Whilst the strength of magnetic flux varies with temperature, permanent changes only occur when the magnet itself surpasses its Curie temperature, which even for Neodymium (which has the lowest Curie temp of all common magnet structures) is still around 300-350 degrees C. Other magnet structures are higher, generally between about 600-800 degrees C. I believe this is what Protium was referring to.

In extended use, loudspeaker drivers (and their associated magnets) will often be heated to temperatures much higher than even the hottest car would ever get.

If a GPS, phone, ipod, stereo, laptop or whatever else might be left in a car can survive, I'm sure a bass cab will be fine. Provided it doesn't get nicked, mind.

[BasH]

[quote name='escholl' post='1280393' date='Jun 24 2011, 01:19 AM']Whilst the strength of magnetic flux varies with temperature, permanent changes only occur when the magnet itself surpasses its Curie temperature, which even for Neodymium (which has the lowest Curie temp of all common magnet structures) is still around 300-350 degrees C. Other magnet structures are higher, generally between about 600-800 degrees C. I believe this is what Protium was referring to.

In extended use, loudspeaker drivers (and their associated magnets) will often be heated to temperatures much higher than even the hottest car would ever get.[/quote]

That's what I always assumed as well. But apparently prolonged exposure to changing temperatures might induce permanent change/damage as well (so leaving it in your car for a few days wouldn't be a problem, but several years would).
But I think it might be more damaging to the plywood and tolex than the magnets...

[quote name='escholl' post='1280393' date='Jun 24 2011, 01:19 AM']If a GPS, phone, ipod, stereo, laptop or whatever else might be left in a car can survive, I'm sure a bass cab will be fine. Provided it doesn't get nicked, mind.[/quote]

True, but most of these things don't even last a few years if you treat hem properly

[escholl]

[quote name='BasH' post='1281074' date='Jun 24 2011, 02:53 PM']That's what I always assumed as well. But apparently prolonged exposure to changing temperatures might induce permanent change/damage as well (so leaving it in your car for a few days wouldn't be a problem, but several years would).
But I think it might be more damaging to the plywood and tolex than the magnets...[/quote]
plywood and tolex will be fine, provided they don't get wet. as to your other claim, source? cars have a multitude of magnets in them, not the least of which are in the stereo system (as pointed out by many others here).
[quote]True, but most of these things don't even last a few years if you treat hem properly [/quote]
Right, but if even the more delicate electronics aren't damaged, cabs will definitely not be damaged.

[BasH]

[quote]as to your other claim, source?[/quote]

Sure...

[url="http://onlinelibrary.wiley.com/doi/10.1002/eej.4390930502/abstract"]A study of irreversible demagnetization at low temperatures[/url]

By the way, I agree with you. Leaving your gear in a car for a few days will not do any harm (provided your car isn't at the bottom of a lake).

I just really would advice against using your car as a gear depot for years on end.


And would leave a bass guitar in a car for a single hot afternoon.

Edited June 25, 2011 by BasH

[stoker]

my cousin left his amp in his car over night and had it knicked! what's worse was it was my amp!!!

[escholl]

[quote name='BasH' post='1282424' date='Jun 25 2011, 08:16 PM']Sure...

[url="http://onlinelibrary.wiley.com/doi/10.1002/eej.4390930502/abstract"]A study of irreversible demagnetization at low temperatures[/url][/quote]
do you have access to the rest of that article? given that the abstract doesn't give the conclusions.

the reason I doubt this so much is simply that every time you use a cab at high volume for an extended period of time, the voice coil and thus surrounding magnets will heat up quite significantly -- yet I have never once, ever, heard of a bass cab (or any moving-coil driver full stop) which stopped working due loss of magnetism and thus sufficient flux.

[BasH]

I know. According to the article, it won't stop working. It will just demagnetize a tiny little bit over time.

So the whole discussion isn't about significant (nor probably even hearable) demagnetization, but about the fact that it does happen.