*WHITE PAPER* The Sound of Music - How & Why the Speaker Cable Matters

Like @djones said there's no reflections at audio frequencies.

Also:

1 . There is no clear scale used for any of the measurements. 
2. The measurements and conclusions are inverted. 

Best,

E

Hmmm, does this solve the problem altogether?
http://www.teoaudio.com/products/liquid-audio-cables/

Weighing in on this discussion - I have been wondering about the possibility of using a Litz wire design for the speaker wires.  If you want the complex impedance of the cable to remain flat over the audio range plus adding in consideration for the higher harmonic frequencies then you need to consider proximity effects (skin effect is the proximity effect that most people are familiar with - there are others).  

The skin depth in copper at 100kHz (the upper BW of most good audio amplifiers) is 0.2mm so this equates to a 32AWG wire.  Assuming you want the equivalent of a 12AWG speaker cable then this would equate to the need for 103 individually insulated strands of 32AWG wire to make the equivalent of 12AWG.

The Litz design that I am considering would be based on using 108 individually insulated strands of 32AWG wire.  From a practical construction perspective I would suggest that the individual insulation is colored - say red for the positive and blue for the negative.

The Litz wire would be made in three levels:

1) Take 3 red and 3 blue 32AWG strands and twist them together to form a 6-bunch.  Make sure that the strands are alternated - red, blue, red, blue, red, blue.
2) Repeat step one 36 times to result in 36 6-bunches.  Each 6-bunch should be twisted the same way (e.g. clockwise) and the number of twists per length should be the same for each 6-bunch.
3) Take six 6-bunches and twist these together to form a 36-bunch.
4)  Repeat step three 6 times to result in six 36-bunches. Each 36-bunch should be twisted the same way (e.g. counterclockwise - the opposite to what was used for the 6-bunches) and the number of twists per length should be the same for each 36-bunch.
5) Take six 36-bunches and twist these together to form a 216-bunch.  This should be twisted the same way as the 6-bunches (e.g. clockwise).
6) Apply a length of woven expandable PET sheathing over the cable to provide some physical protection for the finished speaker cable and secure each end of this sheathing with a short length of heat-shrink tubing - approximately 100mm from the end of the cable. 
7) At the 100mm ends of the cable that are not covered in the sheathing separate out all the individual strands into two bunches - 108 red wires and 108 blue wires.
8) Strip 25mm of the insulation from all of the individual strands.
9) Twist all of the blue strands together to form the negative speaker wire and twist all of the red strands together to form the positive speaker wire.
10) Enjoy!

Why would you want 100KHz flat response. You can't hear it, your speakers cannot recreate, and if they could they would likely distort and modulate distortion to audible frequencies.  100KHz amps are mainly to ensure no phase shift in the audio band (and for marketing).

12 awg stranded only drops in resistance about 50% at 100KHz.  You could just use 2- 12 awg stranded, maybe even 1 - 8awg stranded.  18 - 24 AWG would be just as good at 100Khz as 108-32awg and a lot less work.

w.r.t. a liquid conductor, as long as it has inductance, capacitance and resistance (it will), then it will have a characteristic impedance.  However, the only problem to solve is inductance and that would be hard to interleave (for speaker cables).