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signal wiring / chassis grounding - Aikido

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My Aikido is finally taking shape - I made a dovetailed box out of Home Depot pine (to be replaced with expensive stuff later - Walnut, Quilted Maple????). The parts are mounted onto the upper side of sheet steel, with a separate sheet at the back of the box to hold IEC, fuse, connectors.

So, I will use solid earths for both pieces of steel (star-washers, good cable) to tie the metal to the IEC earth.

My main problem is how to deal with the inputs, especially the signal ground.

I have six sources that I want to switch, and rather than have the RCA's on the upper side of the chassis, I will put them on the back, each wired to an Elma switch. The switch is currently on my passive preamp. The RCA's are isolated from the chassis and the ground signal is bussed to a star earth connected to the chassis. A single signal ground connects from the star earth to the Elma switch. Each signal wire is a twisted pair from Cat 5 cable. I had hum before I added the star earth.

OK, so I am wondering what the first signal wiring attempt on the Aikido should be. Should I copy the wiring from the passive-preamp? I cannot remember if the Aikido board actually has pads for signal ground, in which case I could buss the signal ground to the switch, then to the pot, then aikido input (without connecting the star earth to chassis).

I also purchased Canare L-2T2S cable which I have used for interconnects. The twisted pair for the signal, is surrounded by a braided shield, which is only connected to the -ve signal at the source end. I was thinking that if I utilized the same for RCA socket to Switch, then I may simply shunt noise back to the RCA and back out of the amp.

I'd appreciate any suggestions,

Charlie
 
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