Do RCA cables carry voltage?
What should the RCA output voltage be? A good quality RCA audio source should have a voltage rating of around 1-2 Volts and a low impedance. The voltage is the “strength” of the signal and the “impedance” relates to signal integrity once the RCA is plugged into the amplifier.
Does RCA need power?
If you have to plug them into an electrical outlet then they have a built in amplifier and do not need an external amplifier. These are sometimes called active speakers. If they only have speaker cable (wire) inputs then they are passive speakers which require an external amplifier.
Is RCA the same as TRS?
1/4″ TS/TRS is a far superior interconnect than RCA/phono in every way, except size. If you have to choose an output for an instrument, it should be 1/4″ if at all possible. 1/4″ TS cables are more robust, much more easily repairable, and are used throughout the professional audio industry.