See here: https://celestion.com/product/200/f12x200/ I have a Marshall Valvestate 8080 where I removed the amplifier part and re-soldered the speaker, so I can use it as an open-back 112. It's actually quite nice with the original G12T-75 speaker. Great for practice @home. I'm considering buying a F12-X200 as soon as they are released to replace the G12T-75, that way I would have a cheap FRFR/acoustic rig that I could use in any circumstance (home practice, band rehersals, gigs). You think that dropping the F12-X200 in this old open-back cab would work or would it require a purpose built cab to make it sound good ?