Actually, in the case of the 11/44 (and other BA-type cabinets) it is
necessary to mount the rack slides, not the box itself, because you have
to get into it to make changes, fix stuff, impress visitors, etc. And the
rack slides *must* be mounted front and rear, because a loaded 11/44 (or
/34a) weighs somewhat more than 100 lb. The slide flanges are not capable
of holding the load if not suppported at the back of the rack as well.
The only other way would be to shelf-mount the unit, or on wide parallel
flanges underneath (I have done this, using 2" aluminum angles mounted
horizontally to the rack uprights) but still the problem remains of
access... in the case of the /44 and /34a, the weight of the power supply
is toward the back of the box, so that helps out a bit.
All of my current music studio gear is mounted on 2x4s with drywall
screws thru the flanges - works fine so far, though it's a bit 'rustic'.
I just didn't have the money or the time to find suitable racks, so off
to Mountain Builders I went. But nothing I have comes even close to the
loads of as 11/44.... not to mention an RL02, which must be slid out from
the rack to change packs. Ths would be *ugly* in the non-rack-slide
scenario, IMHO.
Cheers
John