Hi Paul
Basically you need a signal-source, a load, & the resulting signal-current flowing through the cable. So let's go through a typical signal-chain...
Let's say that you are breaking in the interconnects from your CDP to preamp & the CDP is running in repeat mode. The interconnect cables running to the preamp will only have signal-current flow if there's a load connected, which means that the CDP's input must be selected at the preamp input. If you have it set to (tuner, phono etc) then the signal-circuit is open & no current flows, thus you are not breaking in that cable. The preamp typically doesn't have to be powered up (unless you have a relay-driven input selector design such as Accuphase --- no power = no relay = no load) but that's an atypical situation.
If breaking in the interconnects from pre to PA then yes of course the pre must be on & passing an input signal through to its' outputs. The signal load is then the amp, & no it doesn't have to be powered on.
If breaking in the amp then yes of course it must be powered on & passing a signal output to speakers or to a resistive dummy load. Just leaving the amp powered on (but passing no signal) will not breakin anything.
Whatever you do, avoid the AC power scenario as posted above. The only time you get involved with that is when breaking in AC power cords. Member Subaruguru (Ernie) has a slick & inexpensive AC adapter harness available for such purposes. It's so cheap & easy to use that I didn't bother to build by own instead.
Basically you need a signal-source, a load, & the resulting signal-current flowing through the cable. So let's go through a typical signal-chain...
Let's say that you are breaking in the interconnects from your CDP to preamp & the CDP is running in repeat mode. The interconnect cables running to the preamp will only have signal-current flow if there's a load connected, which means that the CDP's input must be selected at the preamp input. If you have it set to (tuner, phono etc) then the signal-circuit is open & no current flows, thus you are not breaking in that cable. The preamp typically doesn't have to be powered up (unless you have a relay-driven input selector design such as Accuphase --- no power = no relay = no load) but that's an atypical situation.
If breaking in the interconnects from pre to PA then yes of course the pre must be on & passing an input signal through to its' outputs. The signal load is then the amp, & no it doesn't have to be powered on.
If breaking in the amp then yes of course it must be powered on & passing a signal output to speakers or to a resistive dummy load. Just leaving the amp powered on (but passing no signal) will not breakin anything.
Whatever you do, avoid the AC power scenario as posted above. The only time you get involved with that is when breaking in AC power cords. Member Subaruguru (Ernie) has a slick & inexpensive AC adapter harness available for such purposes. It's so cheap & easy to use that I didn't bother to build by own instead.