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


It goes back to cable manufaturars, mostly provide no relevant data! to sales and the users. None will answer this!
Whay do you think that you own now the optimal cable to your setup?
I think I've figured it out. 


128x128b4icu
@b4icu
Thank you sir, I'm not sure I buy what you're selling..........for free as you say:), but I may look for some 0 awg and give it a try. It could prove interesting..............It's obvious that I have a WAY smaller budget than many here, and my system reflects that. That said, I'm always looking for ways to improve what I hear.........If the "0" gauge wire doesn't do anything for my system, I can always use it to tow a car or something :)
Mr.  shadowcat2016
Please no "Sir". 

Before you spend some money on a 0 AWG speaker cable, I would recommend you an experiment, that might cost you little of nothing.
Get your amp and speakers closer, to shorten the length from 15' to 7-8'. Try to do (with great care and caution) a connection with two jump start cables, of 0 AWG (the heavy duty type).
If that works for you, you may try to get a set for a good price.
I can recommend you my solution.

b4icu..........thank you again. I did have my amp between the speakers until recently, with shorter cables. The spot was inconvenient, but I understand your point, shorter is better.......and less expensive :)............Most here seem to be male, I made that assumption in your case.............My apologies.

Does it all come down to "use the thickest and shortest cable there is" or am I simplifying it way too much?

The idea about jumper cables, as extreme as it may be, seems brilliant for this discussion. If they work, and they should to some extent at least, it would take away a lots of wire statements frequently thrown around on many a thread.

Mr. glupson1

It is not that simple. As if it would, it would be an old story, everybody knows.

In some cases, when the DF is low, as it is often with Tube amplification, a thick and short cable won't help.

For amplifiers with other than A or A/B class (like D-class) it is also not applicable. So it is with none coil speakers (as ribbon).

For the main stream, that do use A/B class and coil loaded, there is a formula to get an optimum thickness, based on the DF and cable length.

However, it is most recommended to have the optimum thickness and length recommended.

Getting thicker or shorter or both, above that optimum, would cost more, but not be of any sonic benefit (improvement).

It is rather recommended to keep the cable shorter, than get it thicker due to its extra length.