I too found that long quattro-fil is head and shoulders the best I've used with my old arc ref1/vt100m2 setup. I A/B compared it to several other cables. It's scary how much better it is. It's speed and transparency really come out when the length increases. In fact I am not sure if I could tell the difference between a six meter length and a 1 meter length.
If you don't want to sell your car, the audio-research litz cable is pretty good with arc equipment. A little shy on the transparency, but very warm, and nice to listen to. Emphasizes the midrange a little. You can get that stuff pretty cheap.
The harmonic tech pro-sil II is a very good cable too. It has a little of the silver harshness, and it's less transparent than quattro-fil, but excellent nonetheless. I think it's the best no 2nd mortgate cable out there. It's colder but more transparent than the ARC litz cable.
There might be some truth to silver harshness with ARC equipment. I also tried some silver audioquest diamond x3 and found I could really hear the harshness. It was very transparent, but definitely not my favorite cable with that combo. I would take the harmonic tech prosil II over it.
If you don't want to sell your car, the audio-research litz cable is pretty good with arc equipment. A little shy on the transparency, but very warm, and nice to listen to. Emphasizes the midrange a little. You can get that stuff pretty cheap.
The harmonic tech pro-sil II is a very good cable too. It has a little of the silver harshness, and it's less transparent than quattro-fil, but excellent nonetheless. I think it's the best no 2nd mortgate cable out there. It's colder but more transparent than the ARC litz cable.
There might be some truth to silver harshness with ARC equipment. I also tried some silver audioquest diamond x3 and found I could really hear the harshness. It was very transparent, but definitely not my favorite cable with that combo. I would take the harmonic tech prosil II over it.