Re: [Elecraft] K3: switching on click -- One wonders...
> Outside of my own equipment, I have worked mixing boards and > commercial sound systems which all thumped on power-on/off. Some loud > enough to nearly blow your hair off. I can think of a fair number of power amplifiers and mixing board monitor amplifiers that include *delay relays* in the speaker lines that leave the speakers disconnected for two to three seconds after power is turned on specifically to prevent the thump (and potential damage to speakers and/or hearing). 73, ... Joe, W4TV On 9/4/2011 8:16 PM, David Herring wrote: > Hi All! > > I know we've milked this one quite a bit, but I do have a point to make that > I think will frame this "power-on thump" issue in a little better light... > > First off, I have K3 #3019 and there is a very detectable power-on AND > power-off thump in the built-in speaker and in the cans. I don't have > external speakers so I can't say about that. > > BUT, what I wanted to point out is that this behavior, this power-on and > power-off click or thump is widespread and not strictly a K3 problem. While > there are others on this list with way more experience in the field of audio, > I can say that in my younger days I was very much an audiophile. I can tell > you with certainty that all the high end audio equipment I owned (and wished > I owned!) thumped when powering on and powering off. > > Outside of my own equipment, I have worked mixing boards and commercial sound > systems which all thumped on power-on/off. Some loud enough to nearly blow > your hair off. > > I have even witnessed this in concert halls -- I'm thinking, as one example, > of the Pacific Amphitheater one night in LA which very clearly had the > power-on/off thump. I can think of others probably if I worked my brain cell > really hard. > > The point is that this phenomenon seems to be part and parcel of the > powering-on and powering-off of solid state audio amplification. As this > exists in the high quality and commercial equipment I've had the pleasure of > working with, I don't feel it detracts from the K3. I think the K3 is > actually in pretty good company. > > I know that being common doesn't make it right...but it probably does > indicate that most in the business don't regard it as particularly important. > > IMHO if it costs more than a nickel to fix, I wouldn't bother. However I > understand that others, perhaps with amplified speakers, are well within > their rights to feel differently. :-) > > Alrighty then...back to the honey-do list... > > 73& Aloha, > Dave AH6TD > > On Sep 4, 2011, at 12:25 PM, Joe Subich, W4TV wrote: > >> >> I suppose the "click" - or in my case a "thump" - depends on the timing >> of the "mute" signal from the controller and the value of the bypass >> capacitor on pin 8 of the speaker amplifier. The chip manufacturer >> recommends 10 uF for the bypass capacitor but I notice that Elecraft >> use 3.3 uF in the K3. The manufacturer's data sheet shows: >> >> Cb (uF) Ton (Ms) >>1.0 120 >>2.2 120 >>4.7 200 >> 10.0 440 >> >> The manufacturer's data sheet also calls for the time constant of the >> input coupling capacitor and Ri+Rf (input and feedback resistors of >> the amplifier) to be less than the turn on time set by Cb. In the >> K3, I don't know how critical the ratio of input time constant to >> turn on time is but the reference design has an input time constant >> less that 5% of the turn on time while in the K3 the input time >> constant is about 30% of the turn on time. >> >> In addition, I suspect there may be some variation in early vs. late >> production due to the change in the DC resistance of the RF choke in >> the DC line feeding the speaker amplifier. >> >> 73, >> >> ... Joe, W4TV >> >> > > __ > 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
Re: [Elecraft] K3: switching on click -- One wonders...
Hi All! I know we've milked this one quite a bit, but I do have a point to make that I think will frame this "power-on thump" issue in a little better light... First off, I have K3 #3019 and there is a very detectable power-on AND power-off thump in the built-in speaker and in the cans. I don't have external speakers so I can't say about that. BUT, what I wanted to point out is that this behavior, this power-on and power-off click or thump is widespread and not strictly a K3 problem. While there are others on this list with way more experience in the field of audio, I can say that in my younger days I was very much an audiophile. I can tell you with certainty that all the high end audio equipment I owned (and wished I owned!) thumped when powering on and powering off. Outside of my own equipment, I have worked mixing boards and commercial sound systems which all thumped on power-on/off. Some loud enough to nearly blow your hair off. I have even witnessed this in concert halls -- I'm thinking, as one example, of the Pacific Amphitheater one night in LA which very clearly had the power-on/off thump. I can think of others probably if I worked my brain cell really hard. The point is that this phenomenon seems to be part and parcel of the powering-on and powering-off of solid state audio amplification. As this exists in the high quality and commercial equipment I've had the pleasure of working with, I don't feel it detracts from the K3. I think the K3 is actually in pretty good company. I know that being common doesn't make it right...but it probably does indicate that most in the business don't regard it as particularly important. IMHO if it costs more than a nickel to fix, I wouldn't bother. However I understand that others, perhaps with amplified speakers, are well within their rights to feel differently. :-) Alrighty then...back to the honey-do list... 73 & Aloha, Dave AH6TD On Sep 4, 2011, at 12:25 PM, Joe Subich, W4TV wrote: > > I suppose the "click" - or in my case a "thump" - depends on the timing > of the "mute" signal from the controller and the value of the bypass > capacitor on pin 8 of the speaker amplifier. The chip manufacturer > recommends 10 uF for the bypass capacitor but I notice that Elecraft > use 3.3 uF in the K3. The manufacturer's data sheet shows: > > Cb (uF) Ton (Ms) > 1.0 120 > 2.2 120 > 4.7 200 > 10.0 440 > > The manufacturer's data sheet also calls for the time constant of the > input coupling capacitor and Ri+Rf (input and feedback resistors of > the amplifier) to be less than the turn on time set by Cb. In the > K3, I don't know how critical the ratio of input time constant to > turn on time is but the reference design has an input time constant > less that 5% of the turn on time while in the K3 the input time > constant is about 30% of the turn on time. > > In addition, I suspect there may be some variation in early vs. late > production due to the change in the DC resistance of the RF choke in > the DC line feeding the speaker amplifier. > > 73, > >... Joe, W4TV > > __ 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
Re: [Elecraft] K3: switching on click -- One wonders...
I suppose the "click" - or in my case a "thump" - depends on the timing of the "mute" signal from the controller and the value of the bypass capacitor on pin 8 of the speaker amplifier. The chip manufacturer recommends 10 uF for the bypass capacitor but I notice that Elecraft use 3.3 uF in the K3. The manufacturer's data sheet shows: Cb (uF) Ton (Ms) 1.0 120 2.2 120 4.7 200 10.0 440 The manufacturer's data sheet also calls for the time constant of the input coupling capacitor and Ri+Rf (input and feedback resistors of the amplifier) to be less than the turn on time set by Cb. In the K3, I don't know how critical the ratio of input time constant to turn on time is but the reference design has an input time constant less that 5% of the turn on time while in the K3 the input time constant is about 30% of the turn on time. In addition, I suspect there may be some variation in early vs. late production due to the change in the DC resistance of the RF choke in the DC line feeding the speaker amplifier. 73, ... Joe, W4TV On 9/4/2011 5:01 PM, John Ragle wrote: > I run K3/100 Ser. No. 4103. It has a relay click on power on, but > nothing from the speakers. Go figure... > > John Ragle -- W1ZI > > = > > On 9/4/2011 4:46 PM, Mike wrote: >> The external speakers have a pretty loud pop at power on. The headphones do >> not. K3 3539. >> >> 73, Mike NF4L >> >> On 9/4/2011 2:13 PM, Stephen Prior wrote: >>> I think that this has been mentioned before, but the K3 has a pronounced >>> turn on click through the loudspeaker. When connected to external speakers, >>> the click is loud and out of character with the quality feel of the radio. >>> It would be a good idea in my opinion if the audio output were to be >>> muted >>> for a fraction of a second after the K3 is turned on. >>> >>> 73, Stephen G4SJP >>> __ >>> 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 > __ 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
Re: [Elecraft] K3: switching on click -- One wonders...
I run K3/100 Ser. No. 4103. It has a relay click on power on, but nothing from the speakers. Go figure... John Ragle -- W1ZI = On 9/4/2011 4:46 PM, Mike wrote: > The external speakers have a pretty loud pop at power on. The headphones do > not. K3 3539. > > 73, Mike NF4L > > On 9/4/2011 2:13 PM, Stephen Prior wrote: >> I think that this has been mentioned before, but the K3 has a pronounced >> turn on click through the loudspeaker. When connected to external speakers, >> the click is loud and out of character with the quality feel of the radio. >>It would be a good idea in my opinion if the audio output were to be muted >> for a fraction of a second after the K3 is turned on. >> >> 73, Stephen G4SJP >> __ >> 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
