I think I have been reasonable other members with something to sell with goofy stories have asked me not to post in their vendors forums and I comply. This is where this belongs.
Oh. I have better ones ..... here is one regarding the special "Q" clearance:What a great story!
I was at a dinner in a nice quiet neighborhood of Georgetown outside of Washington DC. Hang out of the rich and famous and politians. The host had also invited a woman who worked for our government in DC to dinner also. After dinner the woman asked what I did. I was fairly brief -- just where and mentioned I had a "Q" clearance for 25 years.
The woman's eyes got really big. She stopped talking. Fear was on her face. Like she realised she was sitting opposite a serial killer or something worse. Oh, I said, I can see you Know. She didnt say anything more and got up. She was gone a long time talking to my host in another room. When my host came back without the woman friend, i asked where is so and so? All I got for an answer was "She left after you said you had a Q clearance".
True story. First time told.
-Richard
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A scientific method requests for independent verification of new findings by replication of the experiment at a different work place. Joe, I will measure speaker distortion with and without impedance flattening. The speaker impedance looks like
What value of parallel flattening resistance do you recommend for a start? I have power resistors of 6.8 ohm, 10 ohm and higher. Some coils and big foil capacitors as well.
An externally hosted image should be here but it was not working when we last tested it.
What value of parallel flattening resistance do you recommend for a start? I have power resistors of 6.8 ohm, 10 ohm and higher. Some coils and big foil capacitors as well.
True. I know somebody who creatively called in "anti-voltage" in New Zealand. Put that voltage in series with a current, it will restrict the current. It impedes current, it becomes an impedance. Neville Thiele showed this (documented it) way back in the 1960's. This was how he measured the impedance plot of a speaker. He converted volts to Ohm. It's textbook stuff.
I am not trying to troll others, I am simply replying to "benb."
All that BS caused a race to the bottem. We need a 13th rule against irrepairable stupidity or a general unwillingness to learn.
For a better word... this was really... lame? How can you post that - it says absolutely nothing. This strengthen you in the mindset that you are correct and "they" are wrong? Morris??? He called you stupid? Black box is a very helpful architectural concept used to hide complexity when not needed - there could be large or small ones as per need.
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OK, I did it
. As a part of another measurements, it was no problem to add a "flattening" resistor of 4 ohm.Attached is the impedance plot of the speaker. One can see that impedance near resonance goes up to 47 ohm and that it remains above 6 ohm everywhere. So, with 4 ohm "flattening" resistor the impedance will be between 2.4 ohm and 6.4 ohm, values including resonance.
I have measured speaker acoustical output at 15 cm distance from woofer, on woofer axis. At 1Vrms and 2Vrms and 5Vrms amplifier output. Distortion plots are shown for both cases, i.e. no flattening resistor and 4 ohm parallel flattening resistor. The distortion is not changed after "flattening", in other respect than acoustical measurement statistic deviations. So - nothing
.P.S.: Amplifier distortion was below 0.01% in all measurements
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Q Sensitive allow access to Special Nuclear Material (SNM) category 1. An employee with a Q sensitive clearance could have access to nuclear weapons design, manufacture, or use data; disclosure could cause exceptionally grave damage to the nation.
-RM
Three colors are THD (grey), H2 (red) and H3 (orange),
Yes, however it was said about amplifier output distortion. As this is much much lower than that of the speaker, acoustical distortion is unchanged.
All those stories about impedance flattening may be related to some tube amplifiers with high output impedance, to some extent. For SS amplifiers (not speaking about some curious non feedback designs) all the stories about R, RC helping amplifier to deal with EMF are simply a big nonsense.
Thank you, I am sorry I forgot to include the legend in the image.
So, why did she leave?
Is it bad practice to disclose that you had that clearance, since it could make you a target?
Thank you Bill and I agree with the last sentence. However, stories are much more popular and they give absolute freedom in creating "other reality".
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