Is this cabinet design still being used?
 

I saw this Music Man 118 RH cabinet for sale in the TB classifieds and I'm curious about its design. Do builders still use it? Did ports replace that bottom opening? (Sorry, not sure what the correct name for that is.)

I believe this is what they call a folded-horn design. It's a lot less popular than it was, say, thirty years ago. I don't know if any builders are making folded horn bass cabs these days, but I still see a lot of the old ones in use.

In my experience with them - albeit limited - they sound better when you get far out in front of them than they do up-close. The ones I've used were very muddy sounding on stage, but sounded clear out in the house. It may just be that I've only got limited experience with using them. The ones I've played through were part of house backline packages, so I also can't attest to their general health and upkeep, if you know what I mean.

I wonder if hearing it on stage would improve if you flipped it over so that opening was closer to your head?

Fairly likely the hole at the bottom is just a flared port. Generally too short to be horn loaded.

If it improves or gets worse, it'll be for another reason besides getting the port closer to your head.

Acoustic still makes folded horn cabs
http://www.acousticbassusa.com/products/361.html

Folded horn bass cabs are not horn-loaded. They use normal bass speakers. The cabinet design itself is what makes up the horn.

That said, I'm not 100% certain the Musicman cabs are folded horns. It looks like one, for sure, but I can't swear to it. It could just be one big-a** port.

Horn loading is the acoustic phenomenon that makes a horn cab, as opposed to a direct radiator or ported cab.

We used to call them scoops, though that may not be a proper term either. It's a sort of a seat-of-the-pants port design, not a horn. Some other stuff was called slot-loaded, which I guess is a form of a horn?...bit not nearly long enough to load down into the bass frequencies.

A real folded horn is seen in subwoofers, where the long horn path is "folded up" to fit in the box, otherwise your "cabinet" would look like an 8 foot long trumpet flare.

This guy is the only one I know of that is still designing new folded horn cabs: http://billfitzmaurice.info/

I remember calling those "scoops" also will33. Not really a horn design as the size and shape isn't really "tuned" to any useful bass frequencies. A cab like that was the PA subwoofer of its day (in my memory) and obviously got used as a stage bass rig too.

Fliptops.net makes a folded horn design 15.