Ed wrote
"Lying to your K3" may be cute to say, but it detracts from what is really going on. That filter parameter simply sets the DSP bandwidth at which the crystal filter engages, and for all narrower bandwidths until the next crystal filter engages. The crystal filter and the DSP filter can have three basic relationships, all with different results. One filter can be significantly wider than the other or they can be close to the same bandwidth. There are lots of K3s configured in each of these three ways and the users that understand the implications of their particular choice will have one or more reasons for that choice. One popular reason for engaging the crystal filter at a significantly wider DSP bandwidth, is that the shape of the audio passband is "rounder" (because it is dominated by the crystal filter passband shape) and sounds a bit different than when the more rectangular DSP passband dominates, i.e, is narrower than the crystal filter. One popular reason for engaging the crystal filter when the DSP bandwidth is well inside it, is to maintain consistent bandwidth steps as the K3 IF bandwidth is varied via the WIDTH or HI/LO-CUT controls. Users that care about this usually don't confuse the marketing name of the filter, e.g., 250 Hz, with the actual bandwidth, e.g., 370 Hz. Ed - W0YK Ed, I went back and looked at some filter and dsp plots and see that this indeed causes a "softer" filter scenario. Too bad you cant switch on the fly! I may play around with that. I normally use the 2.7 filter. No 2.1. Engage 1.8 at 1.8. I think if I need the filter I would want it sharp as qrm is the reason I'm narrowing the bandwidth. I don't contest and maybe a soft 2.1 is more desirable when "running" a frequency? I'll have to experiment with how it sounds different. Is it more pleasing to the ear? Thanks and 73 Mike R Play me some fiddle, but no stinkin' violin! Amateur/Ham Radio KE5GBC HF & Echolink mobile ______________________________________________________________ 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