Can temperature fluctuations affect audio gear?

The ambient temp can effect speaker performance. I experienced this first hand with a pair of Monitor Audio Studio 20s. Below about 70° the sound would lose its openess. It could be due to the metal cones in the Monitor Audio, but I haven't noticed the effect with other metal cone speakers I've had.

I could easily see how the cold could effect a listeners perceptive abilities both positively or negatively.

I see how I miswrote. But I'll stand by.....that as the temperatures of the room and amp get closer together, heat transfer slows.
Point is, cooler is better and you can cook it in a hot environment.
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?
2 amps of identical efficiency and power rating being run identically will be at different temps depending on the mass of the amp. And we all know how much heatsinks cost.

It's kind of an aside, but look at a few Stereophile amp tests where they 'precondition' an amp at 1/3 power for an hour before bench measurements. Some amps fail.

I'll call a friend of mine who is a PHd in physics. he'll straighten me out. His area of expertise is semiconductors, so it'll be good info.

My system sounds noticeably better in the winter and colder months than it does in the summer. I am not including the sound of the central air or heating system as I have done by listening comparisons with the AC and heat turned off. It seems that the warmer air effects the sound in the room. A close audiophile friend of mine has found the same.

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.

Magfan & Bigbucks, I'll say first that thermodynamics was definitely not one of the shining successes among the courses I took in college, but pending further info from Magfan's PhD friend I believe that Bigbucks is correct.

Magfan: 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?

The maximum rated junction temperature of a semiconductor device, less some derating (margin), is the maximum temperature that is safely allowable. It is by no means the maximum temperature that is "possible." And yes, it can keep getting hotter until its mtbf (mean time between failure) is severely degraded, or until immediate failure occurs.

Think of it this way: If everything has been turned off for a while, everything (including internal device junction temperatures) will be at the room ambient temperature. The energy that is fed into each device, less whatever amount of energy the device outputs to other devices, and less whatever amount of heat is conducted or radiated away from it, can only have the effect of heating the device up from that starting temperature.

Best regards,
-- Al