Rob, NR can be very effective on SSB depending on conditions, but it takes some careful adjustments. Try F7 through F8 settings and I also have to adjust Hi/Lo settings to improve readability of the audio. You can often reduce the watery effect and greatly improve overall readability on a noisy night. Doesn't work all the time -- depending on QRN conditions. I would say about 80% of the time I can achieve a noticeable improvement using NR on SSB when the noise is high. You're not trying to achieve best fidelity with this technique -- just improved readability.
Dave, N4QS ----- Original Message ----- From: <[email protected]> To: "James Sarte (K2QI)" <[email protected]> Cc: "Elecraft" <[email protected]> Sent: Saturday, November 27, 2010 10:07 AM Subject: Re: [Elecraft] K3: noise reduction performance > I'm still getting my sea legs on the K3 but NR seems to work really great > on CW but on SSB, I can't use it. With it on, regardless of setting, it > makes the channel sound "watery" (for lack of a better term). I have two > K3s, and both sound alike on phone with NR invoked. Maybe I don't have > them adjusted properly, but I find the sound very disconcerting. > > Rob K6RB > >> Hello Elecrafters, >> >> Regarding the issue of NR, I know this can be a touchy subject and most >> will >> say its very subjective. This post isn't intended as a complaint or >> criticism. Instead, I hope through constructive discussions, more >> improvements to the K3's NR performance will be realized. I'd like to >> begin >> by saying that Lyle and crew have a done a fantastic job to date with the >> K3's NR. I've had the privilege of watching the K3's NR function improve >> over time. The boys at Aptos should really be commended for listening to >> their customers. >> >> With that said, the recent CQSS has made me realize that there is still >> room >> for improvement. During the SS, I used NR extensively in combination >> with >> RF gain and filter hi-cut/lo-cut/shift settings. NR when used in >> combination with the aforementioned K3 adjustments can and does work >> well. >> The problem that I believe remains however is the algorithm used still >> seems too broad in its rejection calculations; what I mean is that SSB >> settings (i.e. F5-1 and higher) don't seem to be selective enough to >> reduce >> noise while allowing speech patterns to remain unaffected. In other >> words, >> the DSP sounds like its reducing everything within its passband. To my >> ears, the NR doesn't seem to make speech "pop out" quite as effectively >> has >> other NR implementations. This can be seen by a not-so-subtle reduction >> in >> speech volume whenever the NR is turned on. The NR behavior is >> consistent >> regardless of AGC slope or threshold settings. >> >> Below are several links to audio recordings of a product I used to own. >> It >> is called the BHI ANEM (Mk. II). Sadly, I sold it after getting the K3. >> I >> should have hung on to it as it has become my benchmark for NR >> performance. >> >> These are some sample recordings of the ANEM being turned on and off. >> These >> recordings are found on W4RT's website >> >> 20 m SSB <http://www.w4rt.com/BHI/20Mband-ssb.wav> >> 80 m SSB <http://www.w4rt.com/BHI/80conv-ssb.wav> >> 80 m SSB <http://www.w4rt.com/BHI/80Mconv2-ssb.wav> >> >> I've also compared the K3's NR performance to that of the Icom 756 Pro 3 >> which has similar NR reduction properties - albeit not as effective - as >> the >> ANEM. >> >> Perhaps I am being subjective or overly critical, but one thing you can >> easily notice with the ANEM recordings is that speech volume doesn't get >> as >> affected as the K3s. This is really surprising to me as the NR for the >> ANEM >> is AF rather than IF like what's used in our radios. This leads me to >> believe that the ANEM's NR algorithms are more effective in reducing >> background noise while leaving speech unaffected. >> >> What do you guys think? >> >> Sorry for the long email. Many thanks in advance for your >> ideas/suggestions. >> <http://www.w4rt.com/BHI/20Mband-ssb.wav> >> -- >> 73 de James K2QI >> President UNARC/4U1UN >> ______________________________________________________________ >> 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 > ______________________________________________________________ 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
