My comment is not to K6GPW, but to the continuously number of postings regarding Fan Noise.
1) Would someone measure (quantify) the "objectionable" noise (using a sound meter) and report their dB findings. 2) Determine a sound level (measurement) that is acceptable (based upon normal ears). 3) Describe how / where the amplifier is located; possibly the amplifier is in a position where sound is reverberating off a wall, metal file cabinet, wooden or plastic shelf, (possibly the amplifier enclosure itself), etc.. 4) What is the noise specification of the fan in the amplifier provided by the manufacturer - is it being exceeded. 5) How loud is "too loud" - my ears or your ears? 6) Is there an industry standard for reference in measuring the KPA500 "noise"? Someone who is/are audio experts can provide a methodology on how to properly measure (fan) noise. Baseline fan noise must be measured in an environment where other artifacts are not influencing (amplifying) the "real" sound level and away from the operating station to obtain a true level of the fan noise. The measurement methodology must be capable of being duplicated by others with results within instrument accuracies. Next repeat measurements with the amplifier in the operating position. At least, at this time, one would know if there is an increase in "fan" noise level, if the noise increases, it probably isn't the fan. Possibly a simple solution to those with sensitive ears is placing sound absorbing material between the wall and amplifier, or a baffle above the amplifier slanting towards sound absorbing material. Or lastly, just suck it up and live with the "noise". It very well could be, the artifact of undesirable fan noise can, only be resolved by usage of headphones or sell your amplifier - if the price is right, I'll buy yours! "hi" BTW, my KPA500 does not have an objectionable fan noise. I didn't use the word "loud" or "soft: because I do not know what the definition of "loud" or "soft" may be! If I could borrow a noise meter, I'd measure my amplifier and let everyone what a "desirable" noise level should be! "hi" Owner of K1, K2, K3, KPA500, KAT500 and several other pieces of Elecraft products. 73, Dick - W7QHE/4 ======================= Message: 9 Date: Mon, 02 Jun 2014 08:28:28 -0700 From: Fred Jensen <[email protected] <mailto:[email protected]> > To: [email protected] <mailto:[email protected]> Subject: Re: [Elecraft] KPA-500 fan noise Our "Beverage Central" is located in my shack. I was contemplating putting a heat exchanger on the KAP500 PA's and routing cold water from the drink fridge through it. I guess that would class as "re-engineering?" Haven't figured out how to get the plumbing out of the fridge, however. 73, Fred K6DGW - Northern California Contest Club - CU in the 2014 Cal QSO Party 4-5 Oct 2014 - www.cqp.org <http://www.cqp.org/> On 6/2/2014 8:16 AM, Jim Brown wrote: > On 6/2/2014 7:56 AM, AG0N-3055 wrote: >>> You could always try replacing the fan with a quieter fan. I would consider that myself, but only with >>> one recommended by the good people at Elecraft. > > It is generally a bad idea to try to re-engineer a product, especially one that is well designed. In this > > > case, I would consider it a really bad idea. ______________________________________________________________ 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 Message delivered to [email protected]
