I posted about this a long time ago but can't find it now. The quick summary: a 5500 HC shipped from So. California to Toronto. It was a heavy box. We wrapped in light foam to protect the finish, then heavy bubble wrap. With wrapped speaker standing tall, we placed a wardrobe box over the top; these are about 2 ft square by 48 inches and pretty heavy duty cardboard over here. Then, we turned it 180 degrees (standing on the other end) and forced another wardrobe box over theopen end and the first box. In effect, double boxed where it mattered, and lots of bubble wrap.

Hope that's clear. 5500 have less to risk than 8000s. For 8s, I'd also use a solid foam piece covering the top and bottom and maybe line the sides of the box if there was room.

Roon, Technics SL10 turntable, Meridian 218, Jolida tube DAC, Nuforce STA 200 Amp and passive Swallow Acoustics ALS2 speakers