Need to vent tube heat?

This is an easier way to do it and requires minimum hassle:
http://members.cox.net/nsgarch/cooling_fans_top.jpg
The fans are Vantec 80mm square "Stealth" computer case fans (they also come in 60mm, 92mm and 120mm sizes) They are 12V but I run them in parallel from a 9V RadioShack wall wart for silent operation. Unlike most fans of this type, these feature roller bearings for extra quiet operation and believe me, they DO make a difference http://www.vantecusa.com/front/product/chg_page/35/-1
This method allows easy access for cleaning and replacement, and allows the "cooling" to follow the equipment, should your component layout change in the future.

PS: I live in Tucson, just a couple degrees less than Phoenix (usually ;-)
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Hi Miles, for what it's worth, and not to bum you out:

I forgot to mention that by using low voltage direct current fans (12V DC) one avoids inadvertantly producing 60Hz AC hum in nearby interconnects or sensitive circuits. The other issue is that if a 120VAC fan is too noisy, it's hard to slow it down except by putting it in series with heat-producing resistors -- which is what Audio Research used to do in their early fan-cooled amplifiers.

I used to think the 120VAC case fans must have better performance compared to the "wimpy" 12VDC versions, but just for the hell of it, I compared the specs for the $12 Vantec Stealth 120mm size fan to the $50 Home Theater PQ fan you mentioned, and lo and behold, the 12 volt DC version has higher CFM airflow and lower dB noise level than the 120 volt AC version, frankly I was quite surprised.

Newbee - leaving no turn un-stoned, I called Vantec on that issue and it was explained that many newer computer motherboards have built-in heat sensors so that the case fans can be turned on/off or their speed adjusted according to the conditions inside the computer enclosure.

I decided (rightly or wrongly) that implementing that capability in my little DIY audio application was probably going to be more trouble than it would be worth - so I put the whole thing out of my mind ;-)

But if you want to pursue it further and find a simple way to implement that feature, PLEASE share it with us!

thanks, -Neil
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Newbee, that's also my approach (keep it simple.) But like I said, I did check with Vantec first. For one thing, I felt the fans were really more powerful than I needed them to be (although still very quiet) so after I spoke with Vantec, I decided to (simply) use a 9V instead of a 12V power supply, and that was that ;-)

Magfan, just remember that you should not be blowing air AT the component, especially tubes (for exactly the reasons you pointed out -- creating hot spots, unequal coverage, etc.) **Unless of course there's just no other way (but there usually is ;-)

The best use of component cooling fan(s) is to use them to assist/reinforce the natural convection created by the component without fans. I probably should have mentioned that with regard to the picture I linked above.

Similarly, in a room, or cabinet full of components, it's best to have an exhaust fan/or ducted fan at the top or ceiling, with filtered inlet grills at the bottom, or near the floor. In this situation (whole room/cabinet cooling), there are a number of companies that make purpose-built hardware such as http://www.middleatlantic.com

** The one exception I know is Audio Research, which still mounts fans on the bottom of their amps, which then blow air UP over the tubes. A sort of "forced convection".
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Bot -- thanks for the links. It looks like manufacturers are starting to catch up with the needs of the market ;-)

- Neil
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