Re: [Elecraft] K3 Need for compressor
n4lq wrote: It seems that without the compressor it is difficult to obtain full SSB output. I'm listening to a guy right now on 160m in QSO. He had is compression on and as can be expected, was picking up plenty of fan noise from his amplifier. He was advised to turn off the compression. This he did and the fan noise went away but he complained about insufficient drive to his amp and his K3 was only putting out 38 watts now. I don't have a decent peak reading wattmeter but I think weak RF output is a common complaint. It's rather surprising that the K3 doesn't have the option of a peak-holding RF output display, like the S-meter has. I just wonder if Elecraft expects everyone to run some degree of compression? Or are we interpreting the PWR meter on the K3 incorrectly? Mainly the latter. When the K3 says no compression, it's telling the truth. In contrast, most other rigs are using compression all the time - even when the speech processor is turned off - because there is peak limiting due to heavy ALC. The K3 is one of the few rigs that does it right... and because no good deed goes unpunished, it then suffers complaints of weak audio! To equal the compression that's always taking place in most other rigs, you probably *do* need to turn the K3's compression up a little. No harm in that - unlike most other rigs, a moderate amount of compression will simply make you sound louder. However, the complaint about fan noise is a valid one. As the compression is increased, the peak audio stays the same but the background noise comes up. Any transmitter with effective compression will also benefit from a noise gate or some other kind of nonlinear threshold, to reduce the noise background when there's no actual speech. This would be something like VOX, but with a different configurable threshold and hold/release dynamics. To obtain full value from the K3's highly effective compressor, could a noise gate be added to 'Lyle's List', please? -- 73 from Ian GM3SEK http://www.ifwtech.co.uk/g3sek ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] K3 Need for compressor?
How about just using a good mic that is dead to its back and thus leaves out virtually all fan noise? Charles Harpole [EMAIL PROTECTED] Date: Thu, 29 May 2008 08:10:32 +0100 To: elecraft@mailman.qth.net From: [EMAIL PROTECTED] Subject: Re: [Elecraft] K3 Need for compressor n4lq wrote: It seems that without the compressor it is difficult to obtain full SSB output. I'm listening to a guy right now on 160m in QSO. He had is compression on and as can be expected, was picking up plenty of fan noise from his amplifier. He was advised to turn off the compression. This he did and the fan noise went away but he complained about insufficient drive to his amp and his K3 was only putting out 38 watts now. I don't have a decent peak reading wattmeter but I think weak RF output is a common complaint. It's rather surprising that the K3 doesn't have the option of a peak-holding RF output display, like the S-meter has. I just wonder if Elecraft expects everyone to run some degree of compression? Or are we interpreting the PWR meter on the K3 incorrectly? Mainly the latter. When the K3 says no compression, it's telling the truth. In contrast, most other rigs are using compression all the time - even when the speech processor is turned off - because there is peak limiting due to heavy ALC. The K3 is one of the few rigs that does it right... and because no good deed goes unpunished, it then suffers complaints of weak audio! To equal the compression that's always taking place in most other rigs, you probably *do* need to turn the K3's compression up a little. No harm in that - unlike most other rigs, a moderate amount of compression will simply make you sound louder. However, the complaint about fan noise is a valid one. As the compression is increased, the peak audio stays the same but the background noise comes up. Any transmitter with effective compression will also benefit from a noise gate or some other kind of nonlinear threshold, to reduce the noise background when there's no actual speech. This would be something like VOX, but with a different configurable threshold and hold/release dynamics. To obtain full value from the K3's highly effective compressor, could a noise gate be added to 'Lyle's List', please? -- 73 from Ian GM3SEK http://www.ifwtech.co.uk/g3sek ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 Need for compressor?
Charles Harpole wrote: How about just using a good mic that is dead to its back and thus leaves out virtually all fan noise? That only means you don't have a big enough amplifier yet :-) The main thing that reduces fan noise on the outgoing signal is close-talking and turning the mic gain down; but directional microphones then suffer from proximity effects, giving too much emphasis on the bass (cue Jim Brown). And anyway, the fan noise doesn't usually come from behind the microphone. In most shack layouts the amplifier is off to one side, and the noise bounces off the walls and ceiling, and arrives at the mic from all directions. -- 73 from Ian GM3SEK http://www.ifwtech.co.uk/g3sek ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 Need for compressor
Hello Ian! ... Any transmitter with effective compression will also benefit from a noise gate or some other kind of nonlinear threshold, to reduce the noise background when there's no actual speech. This would be something like VOX, but with a different configurable threshold and hold/release dynamics. To obtain full value from the K3's highly effective compressor, could a noise gate be added to 'Lyle's List', please? Instead of a Noise Gate with two or three variables, I've implemented an *experimental* Downward Expander with a single variable (threshold). It certainly kills the background noise here! We're listening... Lyle KK7P PS - Not sure when it'll be in the release code. Higher priority items in the queue at the moment. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] K3 Need for compressor
Steve Using compression here I obtain absolutely superb SSB audio from my K3, it sounds really nice and does not have excessive microphone levels to the point where background noise is a problem. I've had several unsolicited reports saying how good the transmission sounds, it isn't broke so it doesn't need fixing as far as I am concerned. Anyone with sufficient fan noise from an amplifier to be picked up on their microphone should be looking for a quieter amplifier! 73 Dave, G4AON K3/100 #80, Kenwood MC-43S microphone, Acom 1000 linear (they are very quiet) It seems that without the compressor it is difficult to obtain full SSB output. I'm listening to a guy right now on 160m in QSO. He had is compression on and as can be expected, was picking up plenty of fan noise from his amplifier. He was advised to turn off the compression. This he did and the fan noise went away but he complained about insufficient drive to his amp and his K3 was only putting out 38 watts now. I don't have a decent peak reading wattmeter but I think weak RF output is a common complaint. I just wonder if Elecraft expects everyone to run some degree of compression? Or are we interpreting the PWR meter on the K3 incorrectly? Steve Ellington N4LQ at insightbb.com http://mailman.qth.net/mailman/listinfo/elecraft ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 Need for compressor
Intriguing idea, Lyle. Could you expand on it a bit? 73, Bob N6WG - Original Message - From: Lyle Johnson [EMAIL PROTECTED] To: Ian White GM3SEK [EMAIL PROTECTED] Cc: elecraft@mailman.qth.net Sent: Thursday, May 29, 2008 7:09 AM Subject: Re: [Elecraft] K3 Need for compressor Hello Ian! ... Any transmitter with effective compression will also benefit from a noise gate or some other kind of nonlinear threshold, to reduce the noise background when there's no actual speech. This would be something like VOX, but with a different configurable threshold and hold/release dynamics. To obtain full value from the K3's highly effective compressor, could a noise gate be added to 'Lyle's List', please? Instead of a Noise Gate with two or three variables, I've implemented an *experimental* Downward Expander with a single variable (threshold). It certainly kills the background noise here! We're listening... Lyle KK7P PS - Not sure when it'll be in the release code. Higher priority items in the queue at the moment. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 Need for compressor
Lyle Johnson wrote: ... Instead of a Noise Gate with two or three variables, I've implemented an *experimental* Downward Expander with a single variable (threshold). It certainly kills the background noise here! ... We're listening... This would be welcome addition to the K3. Noise gates have been unsatisfactory in my experience, usually being difficult to set up and introducing unwanted clicks and abrupt level changes into the audio stream. A smooth operating downward expander is a far better choice. I currently use a Behringer VX-2000 to drive the microphone input via a -20db voltage pad. My primary reasons for using the unit are the downward expander and the flexible input circuit for balanced microphones (and phantom power if needed). I hope your experiment becomes K3 feature at some point. Gus Hansen KB0YH ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 Need for compressor
Intriguing idea, Lyle. Could you expand on it a bit? Go to URL:http://www.dxatlas.com/VShaper/ and scroll down the page at the last few graphs. 73, Lyle kK7P ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 Need for compressor?
One thing that hasn't been mentioned is that if a guy is complaining about your shack noise being heard between your sentences or even words, it simply means that your signal, to this guy, is extremely strong, and he has his AGC set too fast, so that it tries to follow the audo waveform. Inreasing the AGC time constant (setting it to medium to slow) and/or kicking in the attenuator and/or turning off the preamp, or some combination of these, typically solves the problem (assuming the K3 TX really is set up properly -- not too much mic gain / compression, etc.). Guys have been amazed at how much better I sound after I tell them this. :-) Of course, approaching the issue from the K3 TX side is completely valid as well. Bill W5WVO Ian White GM3SEK wrote: Charles Harpole wrote: How about just using a good mic that is dead to its back and thus leaves out virtually all fan noise? That only means you don't have a big enough amplifier yet :-) The main thing that reduces fan noise on the outgoing signal is close-talking and turning the mic gain down; but directional microphones then suffer from proximity effects, giving too much emphasis on the bass (cue Jim Brown). And anyway, the fan noise doesn't usually come from behind the microphone. In most shack layouts the amplifier is off to one side, and the noise bounces off the walls and ceiling, and arrives at the mic from all directions. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 Need for compressor
If we are talking about modifying the K3 transmit audio, we also might want to look at installing a phase rotator, or phase scrambler. Most male voices are very asymmetrical. This presents a real problem with broadcast radio, especially AM. With US AM transmission, you are allowed 100% negative modulation, and 125% positive modulation. With a proper AM transmitter and audio chain, and the 125% positive limiter disabled, and the right type of a male voice, you can get 175-200% positive modulation while never exceeding 100% negative. Flip the polarity of the audio driving the transmitter, and you will cause carrier clipping on the negative modulation, while never going over 60-75% positive modulation. The broadcast equipment manufactures will many times look at the asymmetrical waveform and flip the polarity of the audio signal. Today, most stations depend on the microphone processor to balance out the microphone audio, by simple phase scrambling of the low end of the audio. This effect smooths out the sound of many male voices. I can turn the phase rotator on and off on my radio stations microphone processors off (Symetrix 528e's), and my announcers will complain that their voices sound a little brittle. If you have ever look at your SSB signal on an oscilloscope, you may have noticed that the waveform goes higher in one direction than another. It might be interesting to experiment with external processors on the effect, or lack of effect that phase scrambling might do for SSB. You can read up on how you can do this at several places: W3AM does a good job at: http://www.w3am.com/8poleapf.html http://www.nu9n.com/am.html http://www.omniaaudio.com/tech/speech.htm http://www.euphonicmasters.com/orban_article.php pdf of above at: http://www.orban.com/support/orban/techtopics/Appdx_Radio_Ready_The_Truth_1.3.pdf tom bosscher K8TB ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] K3 Need for compressor
It seems that without the compressor it is difficult to obtain full SSB output. I'm listening to a guy right now on 160m in QSO. He had is compression on and as can be expected, was picking up plenty of fan noise from his amplifier. He was advised to turn off the compression. This he did and the fan noise went away but he complained about insufficient drive to his amp and his K3 was only putting out 38 watts now. I don't have a decent peak reading wattmeter but I think weak RF output is a common complaint. I just wonder if Elecraft expects everyone to run some degree of compression? Or are we interpreting the PWR meter on the K3 incorrectly? Steve Ellington [EMAIL PROTECTED] ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
