Hello
To be honest - the thought of shipping Duetta's or any other panel Apogee in anything other than a pair of foam lined solid crates sounds scary! BUT I do appreciate how expensive such a thing is to make such things so I will offer this advice;-
BUDGET;-Need 3x cut to size plus 150mm (75mm all round) pieces of 10mm ply, and 4x firm dense foam 60mm thick of the same size, 2 catering rolls of cling film, about 10m of 50mm pipe wrap foam, and a pallet. Some bubble wrap is also useful, and some 50mm countersunk screws. Keep the offcuts of ply (they will not use a full sheet).
Lay down the pallet, and one of the pieces of ply. Stick the foam down on the ply with a few lines of hot melt glue or carpet tape around the edge + across - either will do. Lay down on speaker (face UP) on the foam and mark an outline on the foam. Remove speaker, and dig a recess for the terminals. Wrap speaker with the cling film whilst somebody holds it upright. Leave some air space at the bottom of the tweeter - the wrap is to protect the bass panel from impressions from the foam. Lay the speaker in place - replace wrapped speaker on the foam making sure the terminals hit the recess. If the speakers will be air freighted allow for an air gap to the bottom of the back of the tweeter frame for pressure relief - this being achieved with digging some foam out of the way. You don't need much - a finger size will do.
Next get another of your ply pieces, and glue/tape a piece of foam on each side, and lay over the top of the first speaker, in position. Dig out foam for the terminal recess for the other speaker, and pressure gap as/if required. Wrap the second speaker with cling film, again leaving the air gap at the bottom of the tweeter frame. Lay in place.
Attach your last piece of foam to your last full piece of ply and lay on top of the stack. Feed pipe wrap around the gaps in the foam layers, to protect the edges of the speaker cases.
Lastly - lay some bubble wrap down on the top, arrange the stands on their sides, and cover with a layer of bubble wrap, and a couple of the offcuts of ply. Screw through the gaps into the ply layer being sure your screws are not so long as to significantly pierce through the main top face of ply.
This will do
UP TO TASKBuilding proper 1" box aluminium framed, ply clad, foam lined crates (one per speaker) is a better, safer option - and easier for moving at the ends of the journey (without pallet). Typical build cost without labour is about $400 for a pair of Duetta's - plus a few hours of workshop time to make. All my new speakers leave here in such crates.
Take care - Graz