Au contriare...I dodn't see the accuracy about the voltage input for rated output. My old Marantz needed 1v to the power amp for rated output. The Marantz preamp could also deliver up to 10v output to the power amp. The matching tuner's rated output was 1v. The Crowns I own (D150) had an input sensitivity of 1.19v for rated output. The Citation 11 preamp can deliver up to 6v out, high level inputs sensitivities are 150 to 300 mv.
It could be the difference is speaker sensitivity, room size & decor, and phono cart output. Other factors? Maybe yes there too. (the taper in the volume control comes to mind)
Example: Two years ago I volunteered to provide "entertainment" at my 45th HS reunion. Brought a bunch of 45s to play. Using a Marantz 2252 & some Jensen bookshelf speakers. They never sounded "that" loud at home when I made sure everything was operational, but at the venue, which had no carpeting & only hard faced surfaces, it was more than adequate. Much... no, way bigger room, too.
It could be the difference is speaker sensitivity, room size & decor, and phono cart output. Other factors? Maybe yes there too. (the taper in the volume control comes to mind)
Example: Two years ago I volunteered to provide "entertainment" at my 45th HS reunion. Brought a bunch of 45s to play. Using a Marantz 2252 & some Jensen bookshelf speakers. They never sounded "that" loud at home when I made sure everything was operational, but at the venue, which had no carpeting & only hard faced surfaces, it was more than adequate. Much... no, way bigger room, too.