Agreed. 8.3ns delay is shown for the first sim. That would correspond to ~2.7metres metres in free space. What velocity factor do we assume for the line? If 40%, then the modelled line is ~1 metre.
Zo = characteristic impedance, which is not length dependent.

Thanks for the QUCS info, Bertus.

Vp was 1.49 ns/Ft and 11 feet line for 16 ns. VF was 68%. The Zo should be 125 ohms.

I liked the QUCS program, easy to get around, just couldn't get it to simulate, even following their examples by the letter. The deinstal is not so complete, add-ons modified the path and left files that won't erase, so some manual work was required. I like the LTSpice. The simulations of lossy TLs can be slow.

 

The Zo should be 125 ohms.

For standard cable (bell-wire, coax, mains cable, ...) maybe. If you are trying to simulate impedance-matching a 5 Ohm load via the line, shouldn't Z0 be around the geometric mean of the source and load impedances, say ~2 Ohms?
I'm still puzzled (and it's clear other forum members are too) as to why you are chasing rainbows. Distortion introduced by bell-wire or the like will be at the 0.00....01% level, whereas that produced by the drivers will typically be a few % (see for example this study) and the listening-room acoustics (unless you listen in an anechoic chamber) will likely be even higher .

 

Here is a handy dandy calculator.
I plugged in your numbers from page 1 and it came out 43 ohms. Maybe there is a zero somewhere?
I used Kapton as the dielectric.

http://www.eeweb.com/toolbox/microstrip-impedance

 

For standard cable (bell-wire, coax, mains cable, ...) maybe. If you are trying to simulate impedance-matching a 5 Ohm load via the line, shouldn't Z0 be around the geometric mean of the source and load impedances, say ~2 Ohms?
I'm still puzzled (and it's clear other forum members are too) as to why you are chasing rainbows. Distortion introduced by bell-wire or the like will be at the 0.00....01% level, whereas that produced by the drivers will typically be a few % (see for example this study) and the listening-room acoustics (unless you listen in an anechoic chamber) will likely be even higher .

I was just correcting the Zo for the first sim. Interesting thought re the geometric mean. I thought to lose the signal in one end or the other. It is hard to build an exact match so I an R-C termination network at the speaker end of the cable say if the cable was 3 ohms and the speaker 5.2, use a 0.1 uF cap and a 3 ohm resistor in series, and that across the line. (Also to assure stability of these high capacitance lines to the amp)

How did you arrive at 8.3ns delay for the first sim?

It appears what I observe in my audio room does not always show up in some numbers. I am trying to learn more to understand my observations.

 

Here is a handy dandy calculator.
I plugged in your numbers from page 1 and it came out 43 ohms. Maybe there is a zero somewhere?
I used Kapton as the dielectric.

http://www.eeweb.com/toolbox/microstrip-impedance

The width needs to be 0.75 inch not mil, and that gives 1.64 Ohms.

 

Here is a handy dandy calculator.
I plugged in your numbers from page 1 and it came out 43 ohms. Maybe there is a zero somewhere?
I used Kapton as the dielectric.

http://www.eeweb.com/toolbox/microstrip-impedance

Thanks. I used something like that. the trace is 750 mil and DC 2.8

 

Well, we're getting closer.
Think about how good it's going to sound when you get it to 5.2!

 

I thought to lose the signal in one end or the other

I thought you were trying to lose the noise .

How did you arrive at 8.3ns delay for the first sim?

It's the figure you show in post #50.

 

use a 0.1 uF cap and a 3 ohm resistor in series, and that across the line

Simulation shows that will increase the THD by 0.001%. It will sound dreadful .

 

Simulation shows that will increase the THD by 0.001%. It will sound dreadful .

Use low noise resistors, run at 50*K, stamped made in Nibiru.

Oops my bad x2. Wrong value post #50 should me 18 ns. and yes I meant losing the reflected wave.

Interesting THD LTSpice article using .OPTIONS plotwinsize=0 or .OPTIONS numdgt=7

http://www.audio-perfection.com/spice-ltspice/distortion-measurements-with-ltspice.html