Does anyone know if neutral cables exist

Carl, you can get pure copper(4 nines, I recall), not brass(advertised) RCA's from a brand Kimon Bellas repesents in the US, AXON. They are gold plated, and VERY cheap. They've been on my short list, but I just have yet to see if they make a worthwhile difference. Check him out, or one of his distributors. As you're also a speaker builder, you probably already know where to find these guys. If not, let me know, and I'll pass on the info.

From my experience, I seem agree with Stereophile's assessment of Audioquest. They seem to sound midway between the "soft" cables like MIT(see a LOT of Krell people with these...) & Monster, and the "forward" cables Straightwire, Wireworld, Kimber. Maybe you should try. Look at the ones between their cheap stuff, and the real expensive ones. That being said, I really don't use Audioquest, I have one cable in one of my systems.