No one actually knows how to lculate what speaker cable they need

Pictures:
A 4 AWG connected to a B&W802D:
https://imgur.com/a/42eh3h1
The other end is connected to a 250W PASS LAB power Amp.made for a friend in Israel:
https://imgur.com/a/LF0vyGZ
A set of 0 AWG cables before shipping to my friend in Canada:
https://imgur.com/a/gkuHdcD
An other view of 1 set: 0 AWG 2.5m long, to connect between a 250W EMPTICA power Amp.
and a pair of Vienna acoustics Beethoven speakers:
https://imgur.com/a/qwcIbTn
For both cables, the outcome was noticable.
This is the comment of the 0 AWG cables replacing a 12’ 14 AWG set:

"My initial impressions: It’s like having new speakers. The sound is pure and clean. Minute details are suddenly apparent. The range is amazing. Highs, mid-tones and a new bass that I didn’t know my speakers were capable of.

It feels that for all these years my speakers were being choked, and now can suddenly breathe and have their full voice.

To say I’m happy about my new Lang speaker cables is an understatement. I’m thrilled. Thank you for building these superbly engineered cables to unleash the full potential of my home sound system".

For posting pictures to this site / forum:

Use his site to upload: https://imgur.com/a/42eh3h1

Add a new post. Copy the URL address (https://imgur.com/a/gkuHdcD) and paste it here. It works!

Regarding Mr. Dill’s Q: " What about a double run of 0 AWG wire?
Should be twice as good ...."

The low cable resistance has an optimum value. After that, getting more gauge, would have little or no benefit (sonic) but will cost way more, as more material and labor are involved.

This optimum value need to be calculated. The result, should be rounded up to the next AWG avaliable on the guage table:
https://www.powerstream.com/Wire_Size.htm
Ref. to this table, a 4 AWG cable has a 0.81508 Ohm per 1,000m or
0.00081508 Ohm per 1m to have this as twice as good: 0.406392 Ohm,
requires a 1 AWG cable.
In other words, if you would need a 1m of 4 AWG, by doubling the length to 2m, it would now require a 1 AWG cable. or two 4 AWG in parallel. Two equal resistors in parallel = R/2 (of half the value of one resistor).
If in series, it is 2R (by ohm’s law).

b4icu, I concur about the importance of AWG. You are ripping yourself off in terms of performance by neglecting the power cabling. You have a lot of performance improvements available to you if you seek out aftermarket (or make your own, if you wish) power cords. You are not at the summit. Work with power cords and the system will improve greatly. I do not need to hear your system to know it. 

I know you are quite well versed on the theory. Now, ignore it and follow my advice. You will not be disappointed.  :) 

I am not trying to argue with you, but encourage you to go the next step. 

Copper clad aluminum primary wire for audio? I don’t think so. Terminated into those crappy Nakamichi banana plugs ...

https://www.amazon.com/GAUGE-POWER-GROUND-CABLE-AUDIOPIPE/dp/B0792HLWY6

Mr. Dill, this is not the one you address (Amazone). It is a good 0 AWG cooper wire.
I’ll tell you a secret: All cables are having a nylon sleve over, for a reason: So no one can see what is beneath it.
No one will cut a cable that cost’s a leg and an arm to check it. The cable they use, is no better.
Some are way wors.

Nakamichi banana:
The Nakamichi banana plugs are the best of all I tryed. The part that goes into the binding post, has the best contact area. The same is used in labs. It also can hold wires up to 8 AWG. No other do.
CHORD COMPANY SPEAKER CABLE 4MM BANANA PLUGS (SET OF 2) use the same: http://www.analogueseduction.net/banana-plugs/chord-company-speaker-cable-4mm-banana-plugs-set-of-2....
The Nakamichi are better,

The actual cable, is more than the sum of it’s parts. The genuin testemony of my friend (no commercials) is peaking for itself. Even I was surprised for the good. It simply works and do a big change.

PS. No thanks for solving the attached pictures issue on this site/forum?