I don't know which configuration would be better, or to use 12TC and jumpers. I wanted to post a response just to say that I have found the Hyper Pure copper used in the TC cables to be grain free. I use it throughout my system. I think it's a great bargain.
The 12TC has slightly better extension - I'd say a slightly fuller sound, but the 8TC on one of my systems works fine.
If it were me I'd just do the 12TC I think.
As for jumpers, I make my own using two pieces of Kimber TCX wire (same Hyper Pure copper) and Kimber Postmasters.
How long a run do you need for you speaker cables, by the way?
The 12TC has slightly better extension - I'd say a slightly fuller sound, but the 8TC on one of my systems works fine.
If it were me I'd just do the 12TC I think.
As for jumpers, I make my own using two pieces of Kimber TCX wire (same Hyper Pure copper) and Kimber Postmasters.
How long a run do you need for you speaker cables, by the way?