Much of the magic comes from the speakers used.
18" woofer mated to a large 12 cell horn/compression driver combo.
I’ve never heard WE’s like this, but I have listened to a similar vintage RCA mono system.
Not saying the that the amps are not nice, just that these types of speakers tend to floor me (like A7’s, 19’s and vintage K-Horns for later models).
DeKay