Need to vent tube heat?

Electronics that runs cooler lasts longer. You can use active cooling like fans and Airconditioning for your house. OR you can use passive techniques, like a chimmeny to draw air thru.
You can create problems with either technique. With fans, you can have dead spots with little or no air circulation...blow a fan at a piece of vented gear and you may interfere with the natural upward convection of warm air. Passive cooling needs good design and space. It may be possible, for example to cool power tubes with the addition of a smoke stack around the tube. Vented at the bottom, it will draw in cool air and accelerate it up as it warms.

I am currently designing an isolation space for my components. It will feature forced air cooling with input filter. Dedicated vents and a scheme of vibration isolation. The top will have my bigscreen TV, since I am unable to afford, either space or money, more than a single system.

On my worktable, i have a CPU fan, designed for 12vdc which runs fine off a 9v battery and is almost silent. That another poster uses similar is heartening and I may be on the right track. A large, maybe 120mm fan will move enough air, running on 9v. The rat-shack solution may work, even with multiple fans.

Many years ago, I built a fan cooler for my Carver Cube. It 'plugged' onto the back of the amp an drew air thru it. While very noisy, you couldn't tell, since played loud enough to NEED the fan, you could hear the music down the block.

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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i ran across this kit. I am buying two of these fans and then this kit with thermostat accessory and wall wart. It will keep temp between 81-87.

http://www.noctua.at/pdf/infosheets/noctua_nf_s12b_flx_en.pdf

http://www.coolerguys.com/840556082200.html

Instead of a custom rack, you could use a Salamander Design Archtype rack that is open all around, to let your entire system breath, also making it eaiser to dust. A 5.0 is about 39'' tall 23'' w 16'' d. Has 5 shelves, an can have a stacking kit to add more to it. I keep my tube preamp in it and my tube amp on the side on top of a 2.0 I would not put the amp on the bottom, or all of your components would get heat. On top may work if it is not too heavy, or you don't have a turntable on top. I had a Cary V12R in a 15 x 12 room that ran very hot and used it as a heater in the winter, so it would make a difference on your AC bill. I now have a much cooler running Cary CAD 120s and it'll raise the temp. in the room, but not as much. Keep all of your components cool and as dust free as possible, and enjoy your system. Another thing cool about these racks is that they completely adjustable, so you can have the right amount of clearance for taller components.

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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