Cooling fans for tube amp

I'm far from an expert, but I experienced your same frustration a while back when trying to put a fan on my rack. After doing what you did, I found a very quiet 12v fan here. This is a 12v DC fan meaning it needs a 12v DC power converter like the ones you use to charge your cell phone or run a calculator. I had a few of these laying around, so I used 6v converter. On a DC fan, the speed is varied by adjusting the voltage, so mine is running at half speed (6v vs. 12v). I had some spare urethane dampers that Herbie Audio Labs uses on his tube dampeners, I used these to isolate the fan from my mount. I can't tell if its on or off unless I put my ear right next to it. Even at half speed (~900 RPM) it moves plenty of air. It may be an option for you. E-mail me for more specifics if you wish. Good luck.

So the original link I posted was because the company specializes in low noise cooling solutions. But you still might salvage your installation with newbee's rheostat suggestion (or as I did in a another cabinet, 2 fans in series).

Another suggestion would be to make sure your mounting screw holes are slightly larger than the screws, and add rubber grommets under the screw head as well as a rubber washer between the fan and cabinet (cut out of old innertube). I've done all of this to reduce mechanical vibration into the cabinet which otherwise becomes a nice transducer. However, you'll still need to slow down the fans.

Thanks to both the latest posters. Yes, I do need to get the fan speed down and will look for a rheostat today. 3200 rpms is just too much. As I mentioned above, the fan seemed pretty quiet when I powered it up loose on a table- even at full speed.

Will also get some rubber grommets. I did slightly over size the holes so there is some movement around the long screws. Will probably need longer ones now that I'll add 2 more grommets to each side of the attachment.

If it's still too noisy I'll look for a better fan. This one is off the shelf from RS but appears to be well built. It is a ball bearing style so we'll see if I can get the noise down.

So here's the latest if anybody is still following.

Got a 25 watt rheostat per local electonic store recommendation. Hooked it up wrong initially and then got it right. Installed it in the back of the cabinet. My cabinet is 36" high and is on casters so I can easily move it around on the carpet. Believe me this was smart considering how many times I've already had to move it back and forth to get my set-up right.

Everything is powered off the pre-amp via power strip w/surge protection. Pre is also fused. Just finished a 90 minute listening session at fairly good volume so the amp got to full temp. Fan was set at about 50% so I assume around 1500 rpm, maybe less. Fan sound was negligible with music playing and a bit less than the normal amp hum with ambient room sound( which is pretty quiet here).

So bottom line is the fan kept the amp and other electronics at a very reasonable temp running at about half speed. For good measure I set the fan at full speed for 5 minutes after my session and then shut everything down.

I know there are quieter fans availible but so far I'm happy with the set-up. Oh yeah, and I did install some rubber grommets on the attaching screws between the fan housing on the outside of the cabinet and the wood backing. Not sure how much this helped but it seemed like a good idea regardless.

Thanks again for everyone's input and comments. I hope this also helped someone else out with their own cooling issues.

I went the inexpensive route, nose tanning salon tanning beds run at 240 V. So I took some of the cooling fans from those which are already quiet, then I ran them at 120 V. So they would last forever, and run at half speed and be even quieter.

Alternatively you could research what are the quietest gaming fans for people that overclock their computers , Purchase a 24 V fan and run that a 12 V.