If the K3 is being used by a contest group or dxpedition, for instance, you will have a wider range of hearing sensitivities and these activities force us to concentrate a lot more and use a radio for long periods. On this basis, fatigue due to these artefacts should be eliminated for the benefit of the group, particularly those listening to weak signals. I think the extra filter would be a good investment.
David G3UNA > > > > Joe Subich, W4TV-4 wrote: >> >> >> Here is the genesis of the complaint that the K3 is more >> fatiguing than other receivers. The out of band noise >> (noise above 5 KHz) in the K3 is, as you say, at least 60 dB >> below the peak audio level (actually, I measure it at more >> than 90dB down above 5 KHz). However, the stopband also has >> many leakage products (DAC artifacts) in the stopband some >> of which are as much as 50 dB ABOVE the noise floor. >> >> While these products are well below the desired audio in the >> passband, they are "in the clear" as far a local noise. >> This requires the ear/brain system to subconsciously work >> to reject (filter) the undesired discrete frequency products. >> >> > > But these "artifacts", at least in my observation, are only present when a > signal is present. If they are there when only noise is being received, > they > are below the extremely low out of band noise level. Therefore, whilst I > can > see that they could contribute to unpleasant or tiring sounding audio for > those blessed with acute hearing, I can't see that they would result in > the > receiver sounding noisy. > > ----- > Julian, G4ILO. K2 #392 K3 #222. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
