Rheostat suggestion needed

[duvallite]

I am using 2 Nexus 92mm fans for exhaust, model DF1209SL-3, that I am running at 12v, and I would like to undervolt both of them to about 9v~7v to try and get them just a bit quieter. I want to use a single rheostat to slow them down, but don't know what type or size to buy, and a fan controller will not work for my application. Can someone suggest a rheostat brand, model, and part number that would do what I want done, and also how to hook it up? Thanks.

[feddup]

I know you said you didn't want a controller but if you've got a 5 1/4 bay one cheap simple solution might be

http://www.jab-tech.com/Sunbeam-5-1-4-R ... -2530.html

Simple and straightforward!

[cpemma]

I'm very confused by the Nexus spec - Input power: 0.25 Amp Max, 0.96 Watts.

12V x 0.25A = 3W, 0.96W/12V = 0.08A. Big difference.

Taking the 0.96 wattage figure, resistance is 150 ohms, 75R for a parallel pair, so a 50R 3W rheostat will reduce the pairing's voltage to 12 x 75/(75+50) = 7.2V. Roughly.

You can hook it up like this, but a FanMate will do the job without the guesswork on specs.

A country would help if you want a source.

[clarkkent333]

Sunbeam - cheap, simple, and very very effective. Plus it doesn't use PWM and you can control the entire voltage range.

[duvallite]

Thanks for all of the suggestions. I just ordered two of the FanMate 2 controllers to play around with. At 3.99 each, they are cheap, and sounds like they will do the trick. I will also try the 7v wire mod just to see how that works also.