Contact Count in 115VAC Power path.
One of the reasons cited for upgraded wall outlets (cryo'd or not) is the concern for contact resistance. I was looking at the schematic for my CarverPro ZR1600 power amp, and I happened to notice how many connectors there are between the wall plug and the power supply rectifiers. I hasten to say that all the connectors are good quality hardware, and I have no concerns about the cumulative contact resistance, but I was surprised by the sheer number. Construction of the amp follows modern practice, and I bet that other amps also have many connectors in the 115 vac path.
There are six connectors.
IEC connector assembly in (from line cord)
IEC connector assembly out to chassis fuse holder
Chassis fuse holder in
Chassis fuse holder out back to circuit board
Circuit board out to Transformer Primary windings
Transformer Secondary windings back to circuit board (with copper runs to rectifiers)
In addition to the connectors, there two relay contacts.
Power ON/OFF main relay (This substitutes for power switch contacts).
Remote control power application relay
Also there are two fuses (four more contacts). One fuse is within the IEC connector assembly, and one is the chassis fuse.
QUESTION: What difference does one more contact make (at the wall outlet)?
In the good old days the line cord came through a grommet in the chassis and was soldered directly to a terminal strip that also had the transformer primary windings soldered to it. No power switch: the amp was plugged into the switched outlet on the back of the preamp.
I would be interested to hear an inventory of connectors, switch contacts and fuses for some other audio power amps.