Hi Toby, I believe the 6th fan speed setting is OFF. :-) Your temps look about right to me.
The KPA500 is about as quiet as we can make it for a compact solid state 600W amp. We took special care to select the quietest fans we could get for this application. In general our user feedback has been extremely positive with respect to this. I'm a user too and have not had a problem with it, but my operating habits may be different than yours. Solid state amps must move more air over their cooling fins at a much higher rate than tube amps due to the lower operating temperature difference between transistors vs tubes and the ambient air. The higher operating temperature of tube amps does provide a more efficient flow of energy away from the tube to the much cooler surroundings. Also, since the KPA500 is pretty much automatic in its operation, it certainly can be located away from the operating position. Providing more clearance for cool air flow above and behind the amp will also help. But in general, contest usage of any compact solid state amp is going to generate a higher level of fan noise. Regards, Eric --- www.elecraft.com On 11/8/2012 5:51 AM, Toby Pennington wrote: > Eric, yesterday Don emailed a number of us off list with the things he did > to quieten the fan noise of the KPA500.. > > I will leave it up to him if he wants to post his modifications or not, but > one of the things he suggested was to entirely isolate the fan itself from > all metal sheeting or chassis or the amp. > > He does not utilize metal screws to hold the fan in place now, but uses > other means to hold the fan in place, thereby eliminating vibrations from > the fan from transferring to any other part of the amp. > > He also actually balanced the blades of the fan so there was no noise that > occured from imbalance of the fan blades. > > He did other things but now says his fan speed never gets over a setting of 1 > or 2. > > AS an aside, I tried to determine at what temperatures each fan speed came > on at and am missing one speed. When I first noticed the fan speed came on > it was at 50C;, then 55C, 60C, 65C, and then 70 C. That is only 5 speeds > so I am missing one speed. Can you tell me what temperature setting I am > missing? My thinking is I may be skipping one fan speed somehow and that > could be making the amp overheat faster. > > Thanks for your help. Toby W4CAK > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
