Speaker cable vs. interconnect cable length

Tonyptony...If you use rca inputs/outputs (with an adapter)the interconnect will be an unbalanced interface even if the wires and XLR connectors are configured for balanced use. When balanced interconnects are used in unbalanced mode signal pin(-) is just grounded to the shield.

That's what I suspected. So, in a case of an RCA IC, is it still a better idea to go long IC / shorter speaker cable?

Tonyptony...You will get all kinds of opinions on this. Mine is that if your preamp has output impedance of about 100 ohms or less (ss usually runs around 50 ohms) long interconnects should be no problem. For tube circuitry, where 600 ohms is not uncommon, I would keep the interconnects to less than about 8 ft.

Yes, I have a SS preamp, but I'd be looking at ICs on the order of 20' or so.

If it were me I would go with the 20 foot interconnects.