Do you keep your amps and preamps on all the time

In response to your question, yes, i leave all of my SS gear on at all times. That is, unless there is a horrible storm taking place, i'm doing major work on the system or i'm leaving town. Tube based digital gear ( DAC's ) also remains on but the remainder of the tube gear is turned off and powered up as needed.

Secondly, always make sure that any product that runs hot has adequate airflow. I'm not talking about just during normal use, but at all times. Most amps of higher bias require airflow on ALL sides of them. This means that an amp should be elevated above the platform by an inch or two. If you have the amp directly resting on the platform, you've reduced airflow through the heatsinks. If you have the amp tucked into a rack with solid sides, you've reduced airflow. If you have equipment or shelving in close proximity to the top of the amp, you've reduced airflow. Common sense dictates that the hotter the product runs, the more airflow it needs around, and especially, directly above it.

All of these things are BAD and can cause premature parts failure, erratic operation, reduced performance, etc... While some may say that leaving a hot running product on all the time will cause premature failure, i disagree. If the product is properly designed and the natural convection of heat allowed to occur, my personal thoughts and experience are that more damage is done to this type of gear from massive temperature swings and high levels of in-rush current than any other phenomena. Others may agree / disagree, but i'm putting my money where my mouth is and keeping my gear on. Not only does it sound better ( almost all high bias amps DO improve after achieving full temparature stability ), the gear actually lasts longer. Low bias amps may not be affected in such a noticeable manner, but their sonics and levels of resolution are typically not as good to begin with. Sean
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Sean,
I'd want to add that you've got to make sure that such high-bias amp has plenty enough heatsink area arround transistors. If it's not the case the heat will always accelerate and run to fry not only egg but stake as well.
Some of manufacturers does not realize how to calculate the power dissipated on heat and do not provide enogh of heatsink area.

I agree 100% with Sean and follow the same procedures, Although I must admit I am lax when it comes to addressing the weather factor other than to have appropriate surge protection.

Yes, I do keep my amps and preamps on all the time. My gear doesn't run that hot. Common sense applies. I turn them off when changing cables, long absences, and stormy weather.

I agree with what you have to say Marakanetz. Even with what appears to be a massive amount of "fins", some of these amps are still lacking the proper amount of heatsinking due to the number of output devices and / or bias levels being used. As such, one should NOT take ventilation for granted and that is why i stressed the need for a lot of open area around devices that run hot. It is not uncommon for a high bias design to idle at a temperature between 110* and 150*, give or take. If the amp is running at the edge or above this temperature range, you either need more room above and around it or you should check into methods of low noise assisted cooling.

I've got a "high tech" temperature probe coming and i intend to do some testing with it. I think that the results may be pretty interesting to say the least. Sean
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