[Elecraft] K3 Speaker, Season finale

[Ron D'Eau Claire]

Keep in mind that the requirement is not onerous. A typical "hi-fi" speaker
is NOT needed since the KX3, like all communications receivers, is severely
restricts both the high and low frequency audio response.  

The speaker only needs to reproduce the range from about 300 to 2800 Hz
without distortion and with a smooth frequency response. 

By comparison, a minimal "hi-fi" speaker would be expected to deliver a
smooth response from 50 Hz or less to over 15,000 Hz. 

It's not just communications receivers that have limited fidelity too. Many
A.M. radio stations limit their audio response to between 100 Hz and 5,000
Hz. Some less. But without distortion and a well-controlled response, their
audio can be very clean and pleasant sounding. 

Long ago when I worked on broadcast gear (1950's ;-), A.M. stations pushed
their upper audio response much higher. But, when FM became popular in car
radios, many customers complained that they were "noisy" with lots of hiss.
Of course that's because A.M. radios detect background static while F.M.
radios suppress such noise. A.M. car radio manufacturers discovered that
customer complaints were greatly reduced by limiting the upper frequency
response on A.M. to 5,000 Hz or less. 

I've seen similar observations by many on the reflector here who discovered
that their rig sounded much "quieter" when the equalizer was set to suppress
the upper frequency range. 

73 Ron AC7AC