Need to vent tube heat?

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.

Nsgarch, Out of curiosity, I looked up the fans you mentioned. The site sez that they have an automatic temp control function that is not only a turn on/off but actually controls the fan speed. Interesting and sounds great! But, there is no mention about how the automatic function is dialed in, something that would seem to me to be important, especially if the fans are placed some distance from the heat source.

Are you aware of how this works in actual use?

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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Then the heat control is actually external to the fan - now that makes sense to me.

No, I really have no interest in implementing that 'feature'. Actually, to the contrary, for me simple is better. I do have a tad of residualy noise in my set up (I can only hear it when the music is off, sort of just like another environmental noise) but being an anal audiophile I may give these a try.

Thanks.

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 ;-)