Spiroh, what you are hearing is more correctly called "thermal noise", the residual random noise generated by active electronic circuitry. Assuming you don't have ground loop hum or buzz, the "hiss" from well-designed power amps or the power amp section of a receiver shouldn't be audible more than a foot from the speaker and you certainly wouldn't hear it from a normal listening distance.
Some receivers will generate more thermal noise than a separate power amplifier because of the more densely packed circuitry.
Typically, separate preamps are quieter than the preamp sections of a receiver, especially those with phono inputs, moving magnet or moving coil.
Regards,
Alan
