Can temperature fluctuations affect audio gear?

12-03-10: Magfan
The amount of heat your gear will 'give up' to the environment is related to the difference in temp. If your amp runs at 100f in a 100f room, very little heat will be transferred. In a 65f room, you've got no problems.
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Maybe you were trying to say something else, but it didn't come out right. The electronics will essentially be at a constant delta above room ambient (more or less). If your amp runs at 100F when the room is 100F, it means that at 65F room, the amp would run at 65F. Of course, that isn't going to happen.

If the amp is at 100F when the room is at 65F, then when the room is at 100F, the amp will be at 135F. The heat transfer is constant, that's why the amp runs at a constant delta T above ambient.

12-04-10: Magfan
Heat and temperature are 2 different things.
And NO, the amp won't always be the same temp delta from ambient. In SS, for example, you have a max temp possible....say the junction temp of the devices. In a hot room wont' the difference drop as the room temp approaches junction temp? Or will the junction keep getting hotter until failure? Isn't there an upper limit to the temp of an amp?
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That's the point. The junction temperature of SS electronics is a delta above the board temperature. As the ambient increases, the board temp and the junction temp increase proportionally until evntually you exceed the max allowable device temp and then failrue will result some time thereafter.

12-05-10: Magfan
It would seem that as the ambient temperature and temperature of the electronics got closer and closer, the amount of HEAT transferred would get less and less. It maybe that BigBucks is right, but I don't see it. The constant delta above ambient may work but I just see stuff getting hotter faster than the room it's in....especially if the room is externally heated...sunlight, hot day...etc. At some point, the junction temp of an output device would be nearing limits and be unable to dump enough heat.....thru all forms of shedding...radiation, conduction, convection....(others?) But would that be at a constant delta from ambient?
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From above:
"It would seem that as the ambient temperature and temperature of the electronics got closer and closer"

How does that happen? If the room (equipment) is getting hotter, the components are getting hotter at the same rate (given that everything was in equilibrium in the first place.

The equipment dissipates a given amount of power (at a specific operating load). The power is dissipated as heat through the componet body, thru the board, then out thru the heat sinks. That thermal 'resistance' to heat flow is constant. So, a given heat flow (power dissipation) to ambient thru a fixed resistance must yield a constant delta T at the component end. That's why the component junction temp is a constant above ambient.

And I 'know' this because I work on aerospace electronics where we do thermal analyses all the time. I guess all these years we must've been wrong about increasing component temps by the ambient temp delta ;)