[Elecraft] KPA-500 fan noise

[Phil Wheeler]

I've never heard any of the fans (K3 or KPA500) 
except when I shut down the KPA500 for a  short 
time.  So I need no "criteria" :-)

73, Phil W7OX

On 6/2/14, 7:55 PM, Richard L Diddams, Sr. wrote:
> 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 <k6dgw at foothill.net <mailto:k6dgw at foothill.net> >
>
> To: elecraft at mailman.qth.net <mailto:elecraft at mailman.qth.net>
>
> 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.