Rower,
A simple followup.
Your first post to me included your words.."""information is power. get some.""
You are arrogant without foundation to be so.
I provided actual engineering on skin and cables, most taken directly from UNDERGRADUATE engineering E/M texts.
You "counter" with non peer reviewed content from audio hobbyist websites.
Your technical discussion attempts appear to be cut and pastes from online sources, mainly the same audio hobbyist websites, and how you meld them together tends to be both inconsistent and inaccurate, as though you do not have a real understanding of the topic..
Your attempt at diverting the discussion into one of ego has been seen before.
Like this gem...
Stated by rower::
But, I think some of this deservedly stuck to me with a little bouncing off me and sticking to you. True class keeps its class at all times. Yea, it's tough, I know. We do our best. Me, I'm fine with good information, being corrected and moving on. I don't use my knowledge to go hunting for those that don't without any real regards for the actual topic, just the hunt. Grow some civility with your posts and more will follow. You seem to be aware of this, so why not change it? Witness...
end of quote..
How old are you??? Bounce off me stick to you??? Stick to topic and please post more like an adult.
Enough of the unpleasantries, perhaps that chapter can be left behind? Your call.
1. Skin effect within a wire is NOT correctly calculated via the exponentional equation in the audio bandwidth. Skin effect is not as pronounced as the exponential equation describes. That is because the exponential equation assumes the energy is an E/M wave impinging on hte conductive material, NOT being generated by internal currents. You clearly have a problem understanding this. Do us all a favor, E-mail the owners of the sources you are quoting from , Rod Elliot the owner of sound.westhost, or Gene Delasalle, owner of Audioholics...give them verbatim everything I've stated on skin effect, ask them if I am correct. Both will either agree with what I've stated, or they will go to their trusted sources to ask what the story is. In which case, I might get some e-mails. I haven't been in contact with Rod in years, last time we discussed techniques for measuring doppler distortion in speakers, maybe 8 years ago... Gene, I discussed some article possibilities a few months ago.
2. Cables as t-lines at audio frequencies. Here, I guarantee both of your audio hobbyist website "sources" WILL have to contact higher level technical resources. There are only two sources on this planet I am aware of that understand this and have MEASURED, modelled, and quantified it cleanly. Cyril Bateman, and myself. (there may be more, I am not aware of them). Cyril wrote a really nice but unfortunatly extremely technical article which goes over the heads of most people. I am using this understanding to better a work project. Repeat, actual hardware.
I shudder at making this post so long, but the delays are incomprehensible to me...
Rower Quote/question:
I'd rather have half the knowledge and work towards a solution than all the knowledge and sit there with it. Jneutron, where are "our solutions" as you see them? What attributes do you look for?
End of quote.
Another slap upside the head. And you wonder why you have problems with someone of higher technical proficiency??
I stated that rather clearly before, go back and read. Human ITD discernment is 1.5 uSec interchannel max. Any effect which is in excess of that threshold cannot be discounted as inaudible. When the line/load mismatch is such that current group delay exceeds that threshold in the mid audio band where our undithered loclaization capability is strongest, method to reduce that delay are required.
Rower quote/question::
Jneutron, where should user's of Zobel networks calculate the impedance? What do you use when you suggest cable "impedance"?
End of quote..
I already stated that, you either missed it or did not understand it.
When a t-line is terminated by a load which matches the line, the amplifier DOES NOT SEE A CAPACITANCE. It sees a resistance. That is INDEPENDENT of the characteristic impedance of the cable. If you run a 5.77 ohm cable with 300 pf per foot and 10 nH per foot, into a 5.77 ohm load, the amplifier sees NO CAPACITANCE. NONE. You need to understand this.
When the load becomes higher impedance at higher frequencies, THEN the amplifier will see capacitance. It is a consequence of the line to load mismatch, NOT a consequence of the cable per foot capacitance in isolation.
When the load "unloads" at higher frequencies which are BELOW the amplifier's open loop unity gain bandwidth, the phase margin lowers and the system will be marginally or entirely unstable. A zobel is used to load the line at frequencies the speaker will unload at.
At audio frequencies, if you wish to know what the amplifier "sees" given the line impedance and the load impedance, just calculate the energy stored in the cable.
When line equals load, the inductive and capacitive energy storage will be equal, and it will be a minima. The amplifier will see a resistor.
When the line is much higher than the load, inductive energy storage will dominate.
When the line is much lower than the load, capacitive energy storage will dominate.
And, regardless of the ratio, all energy that is stored in the inductance and capacitance will make it to the load. I know full well where you get this dissipation schtick wit respect to capacitance and inductance, I've seen that site. AND IT"S WRONG. Both storage mechanisms introduce phase lag, not dissipation.
My post consists of technical theory and practice within the disciplines of E/M physics, amplifier design, and human localization. You would be better served asking questions on entities you either lack understanding of, or have a different opinion. Using audio hobbyist website content as technical argument material has it's limits.
Needless to say, you spouting t-line approximations which were taught for the RF guys is a waste of time. You do understand that it is taught that way so that we can use smith charts, right?
Geoff, you crack me up. btw, you never answered my question..how have you been? I hope all is well with you.
jn