[Kenwood] TS950SDX: Temperature & fans

Fri Nov 20 12:14:17 EST 2009

By replacing the original fans in my TS950SDX with Noctua NF-R8 low noise fans I have reduced the overall noise level considerably. Only one fan does not live up to my expectations, and that is the fan below the internal speaker.
1) During operation it sleeps the first 5-10 minutes, until the temperature on the final heat sinks rises to app. 30 degrees C. It then runs at low speed and is barely audible. 
2) When the temperature rises to app. 38 degrees C, the fan starts running at high speed. The fan noise is now clearly audible behind incoming signals, and that is the problem.
3) At app. 50 degrees C the rear fan kicks on and starts running at low speed. As the temperature during operation remains well above 38 degrees C, the center fans continues running at high speed, until the radio is turned off.
4) During one hour of operation the temperature on the final never rises about 55 degrees C.
Is this normal behaviour for a TS950SDX? The road to perfection is long and tiresome, but we are closer than ever before.
73 de Peter
OZ8CTH