Hi Joe, You wrote: >> > Please NO! I already run RX Audio bands 1 and 2 at -16 dB to >> > eliminate excessive bass - no more bass, please!
You also wrote: > 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. On Paul's mods, I've been there and done that on both a stock K3 and a modified one. I still don't hear the excessive bass you were mentioning and more important I can't measure it! I went back this morning and measured the speaker out and for that matter all other outputs for fun. When I go to RX EQ bands 1 and 2 and put them at -16 dB I see a gentle roll off starting at 200 hz. However I see the same gentle roll off at zero dB on RX EQ bands 1 and 2. On the line output I see a little less bass than the other outputs and I would expect this since it has a transformer in line that the speaker and phone output doesn't. In fact I don't see a change if I go crazy boosting RX RQ bands 1 and 2. Joe, I am not complaining mind you, I am just not seeing this excessive bass you posted in your message at zero or a huge reduction in bass response at -16 on bands 1 and 2. LO cut is still at 0, I am still on LSB at 2.8 BW. So I am still must be missing something here. BTW this K3 has all the AF, speaker mods, per the K3 Enhancement and Application Notes page. Also I do run from time to time a nice bookshelve and external amp speaker system. The walls are very safe here from excessive bass response. 73 de jay/w5jay.. > >> 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 > >> >> >> 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 >> > >> > >> > >> >> >> >> >> >> 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 ______________________________________________________________ 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
