search BIFOLD doors or room dividers...Doors Plus has a bifold wardrobe door and may be able to source the bigger doors you need

Doors PLus also fit and supply stacking doors, which may suit your needs. Check their website?

I didn't read your question properly - my apologies. I *think* they may have a bottom rail option? Anyway, Good luck!!

You will probably need to get something bespoke (and expensive) built, or look towards a more commercial answer. I probably wouldn't use standard internal hollow core doors if you are trying to reduce the transfer of sound from a media room. However if you use solid-core doors, which will be better at reducing the sound, they will have a lot more weight, so it will be quite tricky recessing the top track into the ceiling, and making sure it is adequately fixed to the existing structure to support the weight. This is not the sort of job for your typical carpenter.

I would suggest you do some research on "Operable Wall", which is the term architects use for openable walls with acoustic properties, such as this one:

https://lotusdoors.com.au/products/80-Series-Operable-Wall

These operable walls are designed to reduce the acoustic problems between adjacent spaces. Best of luck in finding a nice looking one that suits your home,

Regards

Alistair McLean

Dr Retro

of Dr Retro House Calls

Wow that sounds expensive, how wide is the opening, I don't think that you need to spend a whole lot of money on solid timber or acoustic doors, sliding or bifold doors never control sound that's better done with flooring, ie: carpet, furniture and soft furnishings. I still feel that if you spoke to a local cabinet maker, wardrobes/kitchen, builder etc you would achieve a less expensive result to do the same job, they would also have a slimmer profile and less obtrusive when folded back. A builder can fit the track to hold the doors. An excellent place to look for door Architectural fittings is Style Finish in Cammeray in Sydney and online.

https://www.stylefinishdesign.com.au/ cheers