Anyone know ?

What product in this link to Abbey Road studio controls the volume of the B&W speakers ?
The EMI mastering console.
Looks like the link did not go to room 25 as i wished . Any studio experienced agoners out there ? What is a viable method other than a console ? sounds more expensive than preamps made for audiophiles .I have been looking at monitor volume controls from  Crane Song , Coleman , Grace Designs . ect ...
Who used this studio ? What kind of feedback?