Greg: Not a 50 ohm pot. I've built a custom enclosure for my audio equipment and I'm using (2) parallel wired 92mm computer case(2.1W/0.39amps @)fans mounted at the top to vent it. They are powered by an old Rat Shack 12V DC 1amp 25watt power supply. I've plugged the p/s into the "Switched" AC output on my HK525. I need the pot to adjust the fans. I've been told that a pot higher the 50 ohms will have to much resistance. I gotta go to bed, I'm outta' here!
John's right. You'll need a potentiometer/rheostat with a minimum 25 watt rating to control those fans, or else you'll smoke the pot (ok, that didn't come out right!) . Or use an adjustable voltage regulator circuit instead of just a pot. Or get one of those universal AC adapters with the voltage switch (usually 3, 4.5, 6, 7.5, 9 volts). With that you can set the voltage to whatever drives the fans at the speed you want.