> Looking at Spectra right out of the Phones output, I don't > see where bands 1or 2 do all that much in lowering K3's bass.
You won't see much on the headphone output because of the 10 uF coupling capacitors. The effect is quite obvious on both the speaker output and the line output (if you have made the line out modification [R19/20] in K3AF Mod Rev 3). If you replace the 10 uF headphone coupling capacitors with 330 uF caps as recommended by W9AC the headphone output will more like a good external speaker. 73, ... Joe, W4TV > -----Original Message----- > From: Jay Bromley [mailto:jayw5...@gmail.com] > Sent: Monday, April 06, 2009 7:47 PM > To: li...@subich.com; 'Roy Morris'; elecraft@mailman.qth.net > Subject: Re: [Elecraft] K3 Hissy and Noisy Audio > > > Hi Joe, > Looking at Spectra right out of the Phones output, I don't > see where bands > 1or 2 do all that much in lowering K3's bass. > > Having the rig on SSB using the 2.7 Khz filter, the "Lo" on > 0, I see no > change on bands 1 and 2 when I set them to -16. What I am > missing here? I > have never seen or heard too much bass in the K3. > > I did a plot at 0 dB, one at -16 on band 1 and another one on > -16 on band 2 > if anyone would like to see them. > > 73 de w5jay/jay.. > > > > > > >> Perhaps NR could also be improved with more low > >> frequencies in the passband. > > > > Please NO! I already run RX Audio bands 1 and 2 at -16 dB to > > eliminate excessive bass - no more bass, please! > > > > The hiss many seem to be complaining about is broadband > noise in the > > audio (speaker) and/or headphone amplifier. It is more noticeable > > when driving low impedance loads (8/16 Ohm) due to the > relatively high > > gain (14 dB) of the speaker amplifier and the high > frequency boosting > > effect of the 33 pF capacitors in parallel with the gain setting > > (feedback resistors). > > > > 73, > > > > ... Joe, W4TV > > > > > > > > > >> -----Original Message----- > >> From: elecraft-boun...@mailman.qth.net > >> [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Roy Morris > >> Sent: Monday, April 06, 2009 2:01 PM > >> To: elecraft@mailman.qth.net > >> Subject: [Elecraft] K3 Hissy and Noisy Audio > >> > >> > >> I concur with what has been said regarding the "hissy" audio. The > >> receiver audio seems to be on the mid-range to high frequency side > >> without enough low frequencies in the passband. > Experiments with RX > >> EQ apparently have not done anything to eliminate this hiss, but > >> maybe the firmware can be adjusted to increase the low-end > response > >> of the receiver passband. If this doesn't work, maybe a component > >> change is in order. > >> > >> I also think the noise reduction is too sharp in both SSB and CW. > >> Perhaps NR could also be improved with more low frequencies in the > >> passband. > >> > >> Roy Morris W4WFB > >> K2 #2225 > >> K3 #323 > >> K3 #2810 > >> ______________________________________________________________ > >> 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 > > > > ______________________________________________________________ > > 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 > ______________________________________________________________ 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
