I don't know
probably has something to do with the M80" are 39" tall and the middle of the botton tweeter and Midrange is 27" from floor.
Currently my M22 to the top is 45" and middle of tweeter and Mid range is 40"

Sitting in my chair my ears are 30" from floor
I am 10" from front of tv center
10'7" from the M22 L/R
They are wall mount on the FMB's
The image is about dead centre of my 65" tv
and seem to be floating about the front of the VP160.
I am currently in Stereo sound and I would swear if the front of the Pre/Pro was blanket out, I would swear it was the centre channel turned on.
I cannot get a better image

Connect up the M80 and frigg around for hour and the voices in Stereo I swear are at my knee height. it is like it is coming out from under the VP160.
The VP160 is on a home built stand with no bottom and the top is directly level with the bottom of my tv. The bottom of the VP160 is 20.5" off the floor bottom of my tv is 30" off the floor. Centre of the tv is 46" off floor.
I can play and raie up the M22 about 8 " and the image would be dead centre. But, just looks a bit wierd


Anthem MRX520
M5HPv4
VP160HPv4
QS10v4