Length of speaker cables

I don’t know how to answer the question. The mono blocks are Krell 575XD. Already purchased 6 ft William Tell Zeros

Mr. steven0713

The DF is 530 (https://www.krellhifi.com/products/solo-575-xd-mono-amplifier/technical-specifications/).
It’s a relatively high DF.
For 6ft a #0 AWG is recommended.
But why 6ft.?
As your Krell 575XD is equipped with XLR input, use as long as you wish XLR to XLR between the monoblocks and the your Pre.
Use as short cable as you can between the speakers and the Amps.
If you would go down to 3ft (1m) you could do with #4 AWG.
If you could do 1.5ft (0.5m) you could use #8 AWG.
This is why monoblocks: to be placed as close to the speakers.
So you better use it and go that way...

This is a cable you can work with, to connect to such banana plugs:
https://www.ebay.com/itm/8x-Nakamichi-24k-Gold-Plated-Audio-BFA-Banana-Speaker-Plug-Screw-Cable-Wire...
Find a US supplier, as China / Hong Kong do not have shipping because the COVID-19 blockdown. (US price: less than $10.-)
Find an #8 AWG OFC cable (USA made) on eBay and order some.
A simple soldering would make the desired connections (don’t use the mini screws supplied).
I guarantee that this is the best and lower cost solution you may get.
Even a thicker cable, won’t improve sound.
Any thinner or longer, will sound less good.
Tested and proven mathematically.

@b4icu,
If I read it correctly, the 6 foot cables are the speaker cables, not interconnects.
And, though your 8 guage wire will probably sound good, I can tell you it won't hold a candle to AQ cables, let alone the William Tell.
- And, this is coming from a person who didn't believe cables could make a significant difference.- That is, until I listened to them with my own ears.
Bob

Hi bob

At a time you believe in what you hear, I am a guy that do engineering and science. There is a way to calculate a cable’s thickness using DF and length. So I just did.

We are way beyond the acknowledgement that speaker cables do effect sound. The only problem is that you do not whay and what to do to maximize it. I do!

Do AQ cables or William cables do?
I’m sure they don’t. Even the big names have no idea what they are doing. Trust me on that.

The nice thing is, that if you would like to improve that result, let’s say by adding thickness to the cable, beyond that figure I calculated, there will be no improvement in sound!
6 ft is for a short speaker cable for a stereo amp. Not for two monoblocks.
If you went for monoblocks, spending the money and space, take advantage of it. Make your speaker cables as short as you can.
That’s the right and best way to do it.

@b4icu,
Yes, science can help determine things, but one issue is what is being measured and how it relates to human hearing. - The latter being a variable that has no one set status, as each individual has different hearing abilities. This alone renders any scientific interpretation moot.
Add to this that even though your engineering and science measurements relate to something measurable (say electrical conductivity), it has no relation to sound quality.
And, if you are serious about scientific and engineering, then why not put them to the test? I would be interested in your results.
Bob